From d2edd90479abee88f5232af6fa451b00ece43653 Mon Sep 17 00:00:00 2001
From: Alexey <247128645+axkurcom@users.noreply.github.com>
Date: Wed, 26 Aug 2026 09:16:06 +0300
Subject: [PATCH] WEB: websocket + websocket-lanes as Carrier

---
 src/api/mod.rs                                |   9 +-
 src/api/web_status.rs                         | 141 ++--
 src/api/web_status/details.rs                 |  86 +++
 src/api/web_status/query.rs                   |  11 +-
 src/api/web_status/tests.rs                   |   6 +-
 src/config/hot_reload/tests.rs                |   5 +-
 src/config/load/runtime_web.rs                |   3 +-
 src/config/load/strict_keys.rs                |  11 +-
 src/config/load/validate_web.rs               |   9 +
 src/config/load/validate_web/debug.rs         |   4 +-
 src/config/load/validate_web/memory.rs        |   4 +-
 src/config/load/validate_web/websocket.rs     |  83 +++
 .../tests/load_basic_tests/web_tests.rs       |  60 +-
 src/config/types.rs                           |   4 +-
 src/config/types/web.rs                       |  66 +-
 src/config/types/web_debug.rs                 |   5 +-
 src/maestro/generation.rs                     |  12 +-
 src/maestro/orchestrator.rs                   |   7 +-
 .../tests/send_adversarial_tests.rs           |   4 +-
 src/web/bridge.rs                             | 118 +++-
 src/web/http.rs                               |  38 +-
 src/web/http/body.rs                          |  13 +-
 src/web/http/decoy.rs                         |   1 +
 src/web/http/down.rs                          |   3 +
 src/web/http/response.rs                      |   6 +-
 src/web/http/tests.rs                         |   5 +-
 src/web/http/websocket.rs                     | 461 +++++++++++++
 src/web/http/websocket/driver.rs              | 638 ++++++++++++++++++
 src/web/http/websocket/tests.rs               | 311 +++++++++
 src/web/manager.rs                            | 156 +++--
 src/web/manager/admission.rs                  |  22 +-
 src/web/manager/budget.rs                     | 366 ++++++++++
 src/web/manager/lifecycle.rs                  |  19 +-
 src/web/manager/state.rs                      |  33 +-
 src/web/manager/websocket.rs                  | 313 +++++++++
 src/web/manager/websocket/tests.rs            |  40 ++
 src/web/session.rs                            |  23 +-
 src/web/session/backend.rs                    |  85 ++-
 src/web/session/backend_tests.rs              |  16 +-
 src/web/session/downlink.rs                   |  23 +-
 src/web/session/lanes.rs                      |   9 +-
 src/web/session/uplink.rs                     |  37 +-
 src/web/session/websocket.rs                  | 250 +++++++
 src/web/session/websocket/tests.rs            | 135 ++++
 src/web/trace/exchange.rs                     |  44 +-
 src/web/trace/mod.rs                          |   4 +-
 src/web/trace/sanitize.rs                     |   7 +-
 src/web/trace/store.rs                        |  23 +-
 src/web/trace/store/websocket.rs              | 220 ++++++
 src/web/trace/types.rs                        |  43 ++
 50 files changed, 3642 insertions(+), 350 deletions(-)
 create mode 100644 src/api/web_status/details.rs
 create mode 100644 src/config/load/validate_web/websocket.rs
 create mode 100644 src/web/http/websocket.rs
 create mode 100644 src/web/http/websocket/driver.rs
 create mode 100644 src/web/http/websocket/tests.rs
 create mode 100644 src/web/manager/budget.rs
 create mode 100644 src/web/manager/websocket.rs
 create mode 100644 src/web/manager/websocket/tests.rs
 create mode 100644 src/web/session/websocket.rs
 create mode 100644 src/web/session/websocket/tests.rs
 create mode 100644 src/web/trace/store/websocket.rs

diff --git a/src/api/mod.rs b/src/api/mod.rs
index cee3e82..7126f4f 100644
--- a/src/api/mod.rs
+++ b/src/api/mod.rs
@@ -499,12 +499,9 @@ async fn handle(
 
     let result: Result<Response<Full<Bytes>>, ApiFailure> = async {
         match (method.as_str(), normalized_path) {
-            ("GET", "/web-status") => Ok(web_status::render(
-                query.as_deref(),
-                &shared.web_trace,
-                &cfg.web.debug,
-            )
-            .await),
+            ("GET", "/web-status") => {
+                Ok(web_status::render(query.as_deref(), &shared.web_trace, &cfg.web.debug).await)
+            }
             ("GET", "/v1/health") => {
                 let revision = current_revision(&shared.config_path).await?;
                 let data = HealthData {
diff --git a/src/api/web_status.rs b/src/api/web_status.rs
index bee469c..41ef777 100644
--- a/src/api/web_status.rs
+++ b/src/api/web_status.rs
@@ -1,7 +1,6 @@
 use std::collections::BTreeMap;
 use std::sync::Arc;
 
-use base64::Engine as _;
 use http_body_util::Full;
 use hyper::body::Bytes;
 use hyper::header::{self, HeaderValue};
@@ -9,16 +8,17 @@ use hyper::{Response, StatusCode};
 use tokio::sync::OwnedSemaphorePermit;
 
 use crate::config::WebDebugConfig;
-use crate::web::trace::{
-    StoredTraceRecord, TraceRecord, TraceRecordKind, WebTraceStore,
-};
+use crate::web::trace::{StoredTraceRecord, TraceRecord, TraceRecordKind, WebTraceStore};
 
 const MAX_PAGE_BYTES: usize = 8 * 1024 * 1024;
 const MAX_GROUPS: usize = 1024;
 
+// Record-detail rendering remains isolated from filtering and page layout.
+mod details;
 // Query parsing and matching remain independent from bounded HTML rendering.
 mod query;
 
+use details::{push_body, push_frames, push_headers};
 use query::{GroupBy, StatusQuery, client_ip, parse_query, record_matches};
 
 struct GroupSummary {
@@ -119,11 +119,18 @@ fn push_page_start(html: &mut String) {
 fn push_filter_form(html: &mut String, query: &StatusQuery) {
     html.push_str("<section><h2>Filters</h2><form method=\"get\" action=\"/web-status\">");
     input(html, "window_secs", &query.window_secs.to_string());
-    input(html, "ip", &query.ip.map(|value| value.to_string()).unwrap_or_default());
+    input(
+        html,
+        "ip",
+        &query.ip.map(|value| value.to_string()).unwrap_or_default(),
+    );
     input(
         html,
         "session",
-        &query.session.map(|value| value.to_string()).unwrap_or_default(),
+        &query
+            .session
+            .map(|value| value.to_string())
+            .unwrap_or_default(),
     );
     input(
         html,
@@ -133,7 +140,12 @@ fn push_filter_form(html: &mut String, query: &StatusQuery) {
     input(html, "key", query.key.as_deref().unwrap_or_default());
     input(html, "limit", &query.limit.to_string());
     html.push_str("<label>group_by<select name=\"group_by\" multiple size=\"4\">");
-    for group in [GroupBy::Ip, GroupBy::Session, GroupBy::UserAgent, GroupBy::Key] {
+    for group in [
+        GroupBy::Ip,
+        GroupBy::Session,
+        GroupBy::UserAgent,
+        GroupBy::Key,
+    ] {
         html.push_str("<option value=\"");
         html.push_str(group.as_str());
         if query.group_by.contains(&group) {
@@ -165,11 +177,7 @@ fn summary_row(html: &mut String, name: &str, value: &str) {
     html.push_str("</td></tr>");
 }
 
-fn push_groups(
-    html: &mut String,
-    records: &[Arc<StoredTraceRecord>],
-    groups: &[GroupBy],
-) {
+fn push_groups(html: &mut String, records: &[Arc<StoredTraceRecord>], groups: &[GroupBy]) {
     let mut summaries = BTreeMap::<Vec<String>, GroupSummary>::new();
     let mut overflow = 0usize;
     for stored in records {
@@ -275,7 +283,15 @@ fn push_record(html: &mut String, record: &TraceRecord) {
             "http",
             http.route.as_str(),
             http.method.as_str(),
-            http.status.map(|value| value.to_string()).unwrap_or_else(|| "-".to_string()),
+            http.status
+                .map(|value| value.to_string())
+                .unwrap_or_else(|| "-".to_string()),
+        ),
+        TraceRecordKind::Websocket(message) => (
+            "websocket",
+            message.direction.as_str(),
+            message.message_type,
+            message.payload_bytes.to_string(),
         ),
         TraceRecordKind::Lifecycle(event) => (
             "lifecycle",
@@ -327,32 +343,40 @@ fn push_record(html: &mut String, record: &TraceRecord) {
                 html.push_str(&option_u64(timings.response_body_us));
                 html.push_str(" us\n(kernel flush and TCP ACK are not observed)</pre>");
             }
-            if !http.frames.is_empty() {
-                html.push_str("<h3>frames</h3><table><tr><th>dir</th><th>type</th><th>stream/lane</th><th>payload</th><th>WINDOW</th><th>error</th></tr>");
-                for frame in &http.frames {
-                    html.push_str("<tr>");
-                    for value in [
-                        frame.direction.as_str().to_string(),
-                        frame.frame_type.unwrap_or("-").to_string(),
-                        frame.stream_id.map(|v| v.to_string()).unwrap_or_else(|| "-".to_string()),
-                        frame.payload_len.map(|v| v.to_string()).unwrap_or_else(|| "-".to_string()),
-                        frame.window_delta.map(|v| v.to_string()).unwrap_or_else(|| "-".to_string()),
-                        frame.parse_error.unwrap_or("-").to_string(),
-                    ] {
-                        html.push_str("<td>");
-                        escape(html, &value);
-                        html.push_str("</td>");
-                    }
-                    html.push_str("</tr>");
-                }
-                html.push_str("</table>");
-            }
+            push_frames(html, &http.frames);
+        }
+        TraceRecordKind::Websocket(message) => {
+            html.push_str("<pre>connection: ");
+            html.push_str(&message.connection_id.to_string());
+            html.push_str("\nlane: ");
+            html.push_str(
+                &message
+                    .lane_id
+                    .map(|value| value.to_string())
+                    .unwrap_or_else(|| "-".to_string()),
+            );
+            html.push_str("\ndirection: ");
+            html.push_str(message.direction.as_str());
+            html.push_str("\nmessage: ");
+            html.push_str(message.message_type);
+            html.push_str("\npayload bytes: ");
+            html.push_str(&message.payload_bytes.to_string());
+            html.push_str("\nduration: ");
+            html.push_str(&option_u64(message.duration_us));
+            html.push_str(" us</pre>");
+            push_body(html, "message body", message.body.as_ref());
+            push_frames(html, &message.frames);
         }
         TraceRecordKind::Lifecycle(event) => {
             html.push_str("<pre>event: ");
             html.push_str(event.event.as_str());
             html.push_str("\nstream: ");
-            html.push_str(&event.stream_id.map(|v| v.to_string()).unwrap_or_else(|| "-".to_string()));
+            html.push_str(
+                &event
+                    .stream_id
+                    .map(|v| v.to_string())
+                    .unwrap_or_else(|| "-".to_string()),
+            );
             html.push_str("\nreason: ");
             html.push_str(event.reason.unwrap_or("-"));
             html.push_str("</pre>");
@@ -361,51 +385,6 @@ fn push_record(html: &mut String, record: &TraceRecord) {
     html.push_str("</details></td></tr>");
 }
 
-fn push_headers(html: &mut String, title: &str, headers: &[crate::web::trace::TraceHeader]) {
-    html.push_str("<h3>");
-    escape(html, title);
-    html.push_str("</h3><pre>");
-    for header in headers {
-        escape(html, &header.name);
-        html.push_str(": ");
-        escape(html, header.value.as_deref().unwrap_or("[value omitted]"));
-        html.push('\n');
-    }
-    html.push_str("</pre>");
-}
-
-fn push_body(
-    html: &mut String,
-    title: &str,
-    body: Option<&crate::web::trace::TraceBodySnapshot>,
-) {
-    html.push_str("<h3>");
-    escape(html, title);
-    html.push_str("</h3>");
-    let Some(body) = body else {
-        html.push_str("<p class=\"muted\">capture off</p>");
-        return;
-    };
-    html.push_str("<p>observed=");
-    html.push_str(&body.observed_bytes.to_string());
-    html.push_str(" captured=");
-    html.push_str(&body.captured.len().to_string());
-    html.push_str(" state=");
-    html.push_str(body.state.as_str());
-    html.push_str(" truncated=");
-    html.push_str(yes_no(body.truncated));
-    html.push_str("</p><pre>");
-    let available = MAX_PAGE_BYTES.saturating_sub(html.len()).saturating_sub(4096);
-    let raw_limit = available.saturating_mul(3) / 4;
-    let shown = body.captured.len().min(raw_limit);
-    base64::engine::general_purpose::STANDARD
-        .encode_string(&body.captured[..shown], html);
-    if shown < body.captured.len() {
-        html.push_str("\n[page output truncated]");
-    }
-    html.push_str("</pre>");
-}
-
 fn pagination_url(query: &StatusQuery, before_seq: u64) -> String {
     let mut serializer = url::form_urlencoded::Serializer::new(String::from("/web-status?"));
     serializer.append_pair("window_secs", &query.window_secs.to_string());
@@ -436,7 +415,9 @@ fn format_time(epoch_millis: u64) -> String {
 }
 
 fn option_u64(value: Option<u64>) -> String {
-    value.map(|value| value.to_string()).unwrap_or_else(|| "-".to_string())
+    value
+        .map(|value| value.to_string())
+        .unwrap_or_else(|| "-".to_string())
 }
 
 fn body_mode(policy: &WebDebugConfig) -> &'static str {
diff --git a/src/api/web_status/details.rs b/src/api/web_status/details.rs
new file mode 100644
index 0000000..fd21217
--- /dev/null
+++ b/src/api/web_status/details.rs
@@ -0,0 +1,86 @@
+use base64::Engine as _;
+
+use super::{MAX_PAGE_BYTES, escape, yes_no};
+
+pub(super) fn push_frames(html: &mut String, frames: &[crate::web::trace::TraceFrame]) {
+    if frames.is_empty() {
+        return;
+    }
+    html.push_str("<h3>frames</h3><table><tr><th>dir</th><th>type</th><th>stream/lane</th><th>payload</th><th>WINDOW</th><th>error</th></tr>");
+    for frame in frames {
+        html.push_str("<tr>");
+        for value in [
+            frame.direction.as_str().to_string(),
+            frame.frame_type.unwrap_or("-").to_string(),
+            frame
+                .stream_id
+                .map(|value| value.to_string())
+                .unwrap_or_else(|| "-".to_string()),
+            frame
+                .payload_len
+                .map(|value| value.to_string())
+                .unwrap_or_else(|| "-".to_string()),
+            frame
+                .window_delta
+                .map(|value| value.to_string())
+                .unwrap_or_else(|| "-".to_string()),
+            frame.parse_error.unwrap_or("-").to_string(),
+        ] {
+            html.push_str("<td>");
+            escape(html, &value);
+            html.push_str("</td>");
+        }
+        html.push_str("</tr>");
+    }
+    html.push_str("</table>");
+}
+
+pub(super) fn push_headers(
+    html: &mut String,
+    title: &str,
+    headers: &[crate::web::trace::TraceHeader],
+) {
+    html.push_str("<h3>");
+    escape(html, title);
+    html.push_str("</h3><pre>");
+    for header in headers {
+        escape(html, &header.name);
+        html.push_str(": ");
+        escape(html, header.value.as_deref().unwrap_or("[value omitted]"));
+        html.push('\n');
+    }
+    html.push_str("</pre>");
+}
+
+pub(super) fn push_body(
+    html: &mut String,
+    title: &str,
+    body: Option<&crate::web::trace::TraceBodySnapshot>,
+) {
+    html.push_str("<h3>");
+    escape(html, title);
+    html.push_str("</h3>");
+    let Some(body) = body else {
+        html.push_str("<p class=\"muted\">capture off</p>");
+        return;
+    };
+    html.push_str("<p>observed=");
+    html.push_str(&body.observed_bytes.to_string());
+    html.push_str(" captured=");
+    html.push_str(&body.captured.len().to_string());
+    html.push_str(" state=");
+    html.push_str(body.state.as_str());
+    html.push_str(" truncated=");
+    html.push_str(yes_no(body.truncated));
+    html.push_str("</p><pre>");
+    let available = MAX_PAGE_BYTES
+        .saturating_sub(html.len())
+        .saturating_sub(4096);
+    let raw_limit = available.saturating_mul(3) / 4;
+    let shown = body.captured.len().min(raw_limit);
+    base64::engine::general_purpose::STANDARD.encode_string(&body.captured[..shown], html);
+    if shown < body.captured.len() {
+        html.push_str("\n[page output truncated]");
+    }
+    html.push_str("</pre>");
+}
diff --git a/src/api/web_status/query.rs b/src/api/web_status/query.rs
index 106c2ad..cd09d8f 100644
--- a/src/api/web_status/query.rs
+++ b/src/api/web_status/query.rs
@@ -101,8 +101,9 @@ pub(super) fn parse_query(
                 query.key = Some(value.to_string());
             }
             "group_by" => {
-                let group = GroupBy::parse(value)
-                    .ok_or_else(|| "group_by must be ip, session, user_agent, or key".to_string())?;
+                let group = GroupBy::parse(value).ok_or_else(|| {
+                    "group_by must be ip, session, user_agent, or key".to_string()
+                })?;
                 if query.group_by.contains(&group) {
                     return Err("group_by values must not repeat".to_string());
                 }
@@ -140,11 +141,7 @@ fn parse_positive_u64(value: &str, field: &str) -> Result<u64, String> {
 }
 
 /// Applies the complete filter predicate to one immutable record.
-pub(super) fn record_matches(
-    record: &TraceRecord,
-    query: &StatusQuery,
-    since_millis: u64,
-) -> bool {
+pub(super) fn record_matches(record: &TraceRecord, query: &StatusQuery, since_millis: u64) -> bool {
     !(record.epoch_millis < since_millis
         || query.before_seq.is_some_and(|before| record.seq >= before)
         || query.record.is_some_and(|seq| record.seq != seq)
diff --git a/src/api/web_status/tests.rs b/src/api/web_status/tests.rs
index 5139ec7..f9dc268 100644
--- a/src/api/web_status/tests.rs
+++ b/src/api/web_status/tests.rs
@@ -47,7 +47,11 @@ async fn renderer_filters_groups_and_sets_control_plane_security_headers() {
     .await;
     assert_eq!(response.status(), StatusCode::OK);
     assert_eq!(response.headers()[header::CACHE_CONTROL], "no-store");
-    assert!(response.headers().contains_key(header::CONTENT_SECURITY_POLICY));
+    assert!(
+        response
+            .headers()
+            .contains_key(header::CONTENT_SECURITY_POLICY)
+    );
     let body = response.into_body().collect().await.unwrap().to_bytes();
     let body = std::str::from_utf8(&body).unwrap();
     assert!(body.contains("session_created"));
diff --git a/src/config/hot_reload/tests.rs b/src/config/hot_reload/tests.rs
index 6d0e28b..5cc8f33 100644
--- a/src/config/hot_reload/tests.rs
+++ b/src/config/hot_reload/tests.rs
@@ -114,7 +114,10 @@ fn web_debug_prefix_requiring_deferred_capacity_is_not_hot_applied() {
     new.web.debug.body_prefix_bytes = 3 * 1024 * 1024;
 
     let applied = overlay_hot_fields(&old, &new);
-    assert_eq!(applied.web.limits.max_body_bytes, old.web.limits.max_body_bytes);
+    assert_eq!(
+        applied.web.limits.max_body_bytes,
+        old.web.limits.max_body_bytes
+    );
     assert_eq!(
         applied.web.debug.body_prefix_bytes,
         old.web.debug.body_prefix_bytes
diff --git a/src/config/load/runtime_web.rs b/src/config/load/runtime_web.rs
index e2c8248..5d56073 100644
--- a/src/config/load/runtime_web.rs
+++ b/src/config/load/runtime_web.rs
@@ -50,8 +50,7 @@ pub(super) fn rebuild(config: &mut ProxyConfig) -> Result<()> {
                 client_secret(auth_entry.secret, profile.secret_mode);
             let capability =
                 derive_web_capability(&client_secret[..client_secret_len], vhost.host.as_bytes())?;
-            let key_fingerprint =
-                debug_key_fingerprint(&client_secret[..client_secret_len]);
+            let key_fingerprint = debug_key_fingerprint(&client_secret[..client_secret_len]);
             if !capabilities.insert(capability) {
                 return Err(ProxyError::Config(format!(
                     "WEB vhost `{}` contains profiles with the same client capability",
diff --git a/src/config/load/strict_keys.rs b/src/config/load/strict_keys.rs
index 75aa030..5c153a2 100644
--- a/src/config/load/strict_keys.rs
+++ b/src/config/load/strict_keys.rs
@@ -259,7 +259,9 @@ const LISTENER_CONFIG_KEYS: &[&str] = &[
     "web_trusted_proxy_cidrs",
 ];
 
-const WEB_CONFIG_KEYS: &[&str] = &["enabled", "carrier", "debug", "limits", "timeouts", "vhosts"];
+const WEB_CONFIG_KEYS: &[&str] = &[
+    "enabled", "carrier", "debug", "limits", "timeouts", "vhosts",
+];
 
 const WEB_LIMITS_CONFIG_KEYS: &[&str] = &[
     "max_header_bytes",
@@ -269,6 +271,10 @@ const WEB_LIMITS_CONFIG_KEYS: &[&str] = &[
     "max_frames_per_body",
     "max_http_connections",
     "max_http_handlers",
+    "websocket_bytes_global",
+    "websocket_admission_watermark_pct",
+    "websocket_eviction_watermark_pct",
+    "websocket_http_connection_reserve",
     "max_body_readers",
     "max_body_bytes_global",
     "max_sessions_global",
@@ -319,6 +325,9 @@ const WEB_TIMEOUTS_CONFIG_KEYS: &[&str] = &[
     "body_secs",
     "stream_handshake_secs",
     "long_poll_secs",
+    "websocket_write_secs",
+    "websocket_backpressure_secs",
+    "websocket_eviction_secs",
     "bootstrap_lifetime_secs",
     "reconnect_grace_secs",
     "http_idle_secs",
diff --git a/src/config/load/validate_web.rs b/src/config/load/validate_web.rs
index 0b006cf..20427aa 100644
--- a/src/config/load/validate_web.rs
+++ b/src/config/load/validate_web.rs
@@ -6,6 +6,8 @@ use super::*;
 mod debug;
 // Memory-envelope arithmetic remains isolated from protocol validation.
 mod memory;
+// WebSocket transport policy is validated independently from HTTP body policy.
+mod websocket;
 
 const WEB_FRAME_HEADER_BYTES: usize = 8;
 const WEB_QUEUE_ITEM_COST: usize = 256;
@@ -69,6 +71,7 @@ pub(super) fn validate(config: &mut ProxyConfig) -> Result<()> {
         return config_error("web.carrier=https-lanes requires web.limits.max_http_handlers >= 2");
     }
     validate_timeouts(&config.web.timeouts)?;
+    websocket::validate(config.web.carrier, &config.web.limits, &config.web.timeouts)?;
     validate_vhosts(config)?;
     Ok(())
 }
@@ -327,6 +330,12 @@ fn validate_timeouts(timeouts: &WebTimeoutsConfig) -> Result<()> {
         ("body_secs", timeouts.body_secs),
         ("stream_handshake_secs", timeouts.stream_handshake_secs),
         ("long_poll_secs", timeouts.long_poll_secs),
+        ("websocket_write_secs", timeouts.websocket_write_secs),
+        (
+            "websocket_backpressure_secs",
+            timeouts.websocket_backpressure_secs,
+        ),
+        ("websocket_eviction_secs", timeouts.websocket_eviction_secs),
         ("bootstrap_lifetime_secs", timeouts.bootstrap_lifetime_secs),
         ("reconnect_grace_secs", timeouts.reconnect_grace_secs),
         ("http_idle_secs", timeouts.http_idle_secs),
diff --git a/src/config/load/validate_web/debug.rs b/src/config/load/validate_web/debug.rs
index 2798e2e..10b59a1 100644
--- a/src/config/load/validate_web/debug.rs
+++ b/src/config/load/validate_web/debug.rs
@@ -18,7 +18,9 @@ pub(super) fn validate(policy: &WebDebugConfig, limits: &WebLimitsConfig) -> Res
         );
     }
     if policy.body_prefix_bytes > limits.max_body_bytes {
-        return config_error("web.debug.body_prefix_bytes must not exceed web.limits.max_body_bytes");
+        return config_error(
+            "web.debug.body_prefix_bytes must not exceed web.limits.max_body_bytes",
+        );
     }
     if policy.body_prefix_bytes > limits.debug_bytes_global
         || policy.decoy_body_prefix_bytes > limits.debug_bytes_global
diff --git a/src/config/load/validate_web/memory.rs b/src/config/load/validate_web/memory.rs
index 5c2e494..3fb9666 100644
--- a/src/config/load/validate_web/memory.rs
+++ b/src/config/load/validate_web/memory.rs
@@ -46,9 +46,7 @@ pub(super) fn validate(limits: &WebLimitsConfig) -> Result<()> {
                 .checked_mul(WEB_DEBUG_GROUP_SCRATCH_BYTES)
                 .and_then(|scratch| value.checked_add(scratch))
         })
-        .ok_or_else(|| {
-            ProxyError::Config("web.debug reservations overflowed usize".to_string())
-        })?;
+        .ok_or_else(|| ProxyError::Config("web.debug reservations overflowed usize".to_string()))?;
     let reserved = limits
         .pending_bytes_global
         .checked_add(limits.max_body_bytes_global)
diff --git a/src/config/load/validate_web/websocket.rs b/src/config/load/validate_web/websocket.rs
new file mode 100644
index 0000000..84180d1
--- /dev/null
+++ b/src/config/load/validate_web/websocket.rs
@@ -0,0 +1,83 @@
+use super::*;
+
+const MAX_WEBSOCKET_BATCH_BYTES: usize = 2 * 1024 * 1024;
+const WEBSOCKET_IO_BUFFER_BYTES: usize = 64 * 1024;
+const WEBSOCKET_DRIVER_OVERHEAD_BYTES: usize = 4 * 1024;
+const WEBSOCKET_FRAME_OVERHEAD_BYTES: usize = 14;
+
+/// Validates WebSocket admission, memory, and deadline invariants.
+pub(super) fn validate(
+    carrier: WebCarrier,
+    limits: &WebLimitsConfig,
+    timeouts: &WebTimeoutsConfig,
+) -> Result<()> {
+    if !(1..100).contains(&limits.websocket_admission_watermark_pct)
+        || !(1..100).contains(&limits.websocket_eviction_watermark_pct)
+        || limits.websocket_admission_watermark_pct >= limits.websocket_eviction_watermark_pct
+    {
+        return config_error(
+            "web.limits WebSocket watermarks must satisfy 1 <= admission < eviction < 100",
+        );
+    }
+    if limits.websocket_bytes_global == 0 {
+        return config_error("web.limits.websocket_bytes_global must be > 0");
+    }
+    if timeouts.websocket_eviction_secs > timeouts.websocket_write_secs {
+        return config_error(
+            "web.timeouts.websocket_eviction_secs must not exceed websocket_write_secs",
+        );
+    }
+    if !carrier.uses_websocket() {
+        return Ok(());
+    }
+    if limits.carrier_batch_bytes > MAX_WEBSOCKET_BATCH_BYTES {
+        return config_error(
+            "WebSocket carriers require web.limits.carrier_batch_bytes <= 2097152",
+        );
+    }
+    if limits.websocket_http_connection_reserve == 0
+        || limits.websocket_http_connection_reserve >= limits.max_http_connections
+    {
+        return config_error(
+            "WebSocket carriers require websocket_http_connection_reserve within [1, max_http_connections)",
+        );
+    }
+    let socket_base = WEBSOCKET_IO_BUFFER_BYTES
+        .checked_mul(2)
+        .and_then(|value| value.checked_add(WEBSOCKET_DRIVER_OVERHEAD_BYTES))
+        .ok_or_else(|| ProxyError::Config("WebSocket base reservation overflowed usize".into()))?;
+    let minimum_websocket_progress = limits
+        .carrier_batch_bytes
+        .checked_add(WEBSOCKET_FRAME_OVERHEAD_BYTES)
+        .and_then(|value| value.checked_mul(2))
+        .and_then(|value| value.checked_add(socket_base))
+        .ok_or_else(|| {
+            ProxyError::Config("WebSocket progress reservation overflowed usize".into())
+        })?;
+    if limits.websocket_bytes_global < minimum_websocket_progress {
+        return config_error(
+            "web.limits.websocket_bytes_global must preserve one socket read and write",
+        );
+    }
+    let data_bytes = limits
+        .pending_bytes_global
+        .saturating_sub(limits.control_bytes_global);
+    let queue_progress = limits
+        .max_body_bytes
+        .checked_add(
+            limits
+                .max_frames_per_body
+                .checked_mul(WEB_QUEUE_ITEM_COST)
+                .ok_or_else(|| {
+                    ProxyError::Config("WEB queue progress reservation overflowed usize".into())
+                })?,
+        )
+        .and_then(|value| value.checked_add(limits.carrier_batch_bytes))
+        .ok_or_else(|| {
+            ProxyError::Config("WEB queue progress reservation overflowed usize".into())
+        })?;
+    if limits.websocket_bytes_global > data_bytes.saturating_sub(queue_progress) {
+        return config_error("web.limits.websocket_bytes_global must leave bounded queue progress");
+    }
+    Ok(())
+}
diff --git a/src/config/tests/load_basic_tests/web_tests.rs b/src/config/tests/load_basic_tests/web_tests.rs
index 53a69c6..4390f92 100644
--- a/src/config/tests/load_basic_tests/web_tests.rs
+++ b/src/config/tests/load_basic_tests/web_tests.rs
@@ -64,10 +64,13 @@ fn web_debug_table_uses_debug_name_and_bounded_defaults() {
     assert_eq!(config.web.debug.default_window_secs, 180);
     assert_eq!(config.web.debug.max_window_secs, 900);
 
-    let old_name = format!("[general]\nconfig_strict = true\n{}", WEB_CONFIG.replace(
-        "[[web.vhosts]]",
-        "[web.trace]\nenabled = true\n\n[[web.vhosts]]",
-    ));
+    let old_name = format!(
+        "[general]\nconfig_strict = true\n{}",
+        WEB_CONFIG.replace(
+            "[[web.vhosts]]",
+            "[web.trace]\nenabled = true\n\n[[web.vhosts]]",
+        )
+    );
     let error = load_config_error_from_temp_toml(&old_name);
     assert!(error.contains("web.trace"));
 }
@@ -150,3 +153,52 @@ fn web_ipv6_decoy_uses_a_valid_http_authority() {
     };
     assert_eq!(authority, "[::1]:18081");
 }
+
+#[test]
+fn websocket_carriers_build_runtime_profiles_with_bounded_defaults() {
+    for (name, carrier) in [
+        ("websocket", WebCarrier::Websocket),
+        ("websocket-lanes", WebCarrier::WebsocketLanes),
+    ] {
+        let configured = WEB_CONFIG.replace("https-lanes", name);
+        let config = load_config_from_temp_toml(&configured);
+        let profile = &config.web.runtime.unwrap().profiles[0];
+        assert_eq!(profile.carrier, carrier);
+        assert_eq!(config.web.limits.websocket_bytes_global, 256 * 1024 * 1024);
+        assert_eq!(config.web.limits.websocket_admission_watermark_pct, 75);
+        assert_eq!(config.web.limits.websocket_eviction_watermark_pct, 90);
+        assert_eq!(config.web.limits.websocket_http_connection_reserve, 64);
+        assert_eq!(config.web.timeouts.websocket_write_secs, 30);
+        assert_eq!(config.web.timeouts.websocket_backpressure_secs, 30);
+        assert_eq!(config.web.timeouts.websocket_eviction_secs, 1);
+    }
+}
+
+#[test]
+fn websocket_limits_reject_ambiguous_or_nonprogressing_policy() {
+    let reversed_watermarks = WEB_CONFIG.replace(
+        "carrier = \"https-lanes\"",
+        "carrier = \"websocket\"\n\n[web.limits]\nwebsocket_admission_watermark_pct = 90\nwebsocket_eviction_watermark_pct = 75",
+    );
+    assert!(
+        load_config_error_from_temp_toml(&reversed_watermarks).contains("WebSocket watermarks")
+    );
+
+    let no_http_reserve = WEB_CONFIG.replace(
+        "carrier = \"https-lanes\"",
+        "carrier = \"websocket\"\n\n[web.limits]\nwebsocket_http_connection_reserve = 0",
+    );
+    assert!(
+        load_config_error_from_temp_toml(&no_http_reserve)
+            .contains("websocket_http_connection_reserve")
+    );
+
+    let oversized_batch = WEB_CONFIG.replace(
+        "carrier = \"https-lanes\"",
+        "carrier = \"websocket\"\n\n[web.limits]\nmax_body_bytes = 4194304\ncarrier_batch_bytes = 4194304\nmax_body_readers = 16",
+    );
+    assert!(
+        load_config_error_from_temp_toml(&oversized_batch)
+            .contains("carrier_batch_bytes <= 2097152")
+    );
+}
diff --git a/src/config/types.rs b/src/config/types.rs
index 4538ee4..8c7f3f5 100644
--- a/src/config/types.rs
+++ b/src/config/types.rs
@@ -54,12 +54,12 @@ pub use web::{
     WebCarrier, WebConfig, WebDecoyConfig, WebLimitsConfig, WebProfileConfig, WebSecretMode,
     WebTimeoutsConfig, WebVhostConfig,
 };
-pub use web_debug::{WebDebugBodyCapture, WebDebugConfig};
-pub(crate) use web_debug::web_debug_fits_limits;
 pub(crate) use web::{
     WebRuntimeConfig, WebRuntimeDecoy, WebRuntimeProfile, WebRuntimeVhost, WebStaticAsset,
     WebStaticSite,
 };
+pub(crate) use web_debug::web_debug_fits_limits;
+pub use web_debug::{WebDebugBodyCapture, WebDebugConfig};
 
 fn default_quota_state_path() -> PathBuf {
     PathBuf::from("telemt.limit.json")
diff --git a/src/config/types/web.rs b/src/config/types/web.rs
index 713c4fe..db32ec0 100644
--- a/src/config/types/web.rs
+++ b/src/config/types/web.rs
@@ -18,7 +18,7 @@ pub enum WebSecretMode {
     Dd,
 }
 
-/// HTTP carrier selected for newly issued WEB bridge sessions.
+/// Carrier selected for newly issued WEB bridge sessions.
 #[derive(Debug, Clone, Copy, Default, PartialEq, Eq, Hash, Serialize, Deserialize)]
 #[serde(rename_all = "kebab-case")]
 pub enum WebCarrier {
@@ -27,6 +27,10 @@ pub enum WebCarrier {
     Https,
     /// Give every logical stream independent HTTPS sequencing and polling state.
     HttpsLanes,
+    /// Multiplex all logical streams over one ordered WebSocket.
+    Websocket,
+    /// Give every logical stream an independently owned WebSocket lane.
+    WebsocketLanes,
 }
 
 impl WebCarrier {
@@ -35,8 +39,25 @@ impl WebCarrier {
         match self {
             Self::Https => "https",
             Self::HttpsLanes => "https-lanes",
+            Self::Websocket => "websocket",
+            Self::WebsocketLanes => "websocket-lanes",
         }
     }
+
+    /// Returns whether one carrier owns independent state per logical stream.
+    pub(crate) const fn uses_lanes(self) -> bool {
+        matches!(self, Self::HttpsLanes | Self::WebsocketLanes)
+    }
+
+    /// Returns whether carrier messages use RFC 6455 instead of HTTP bodies.
+    pub(crate) const fn uses_websocket(self) -> bool {
+        matches!(self, Self::Websocket | Self::WebsocketLanes)
+    }
+
+    /// Returns whether all logical streams share one carrier state machine.
+    pub(crate) const fn is_multiplexed(self) -> bool {
+        matches!(self, Self::Https | Self::Websocket)
+    }
 }
 
 /// One access user explicitly exposed through a WEB virtual host.
@@ -114,6 +135,18 @@ pub struct WebLimitsConfig {
     /// Process-wide concurrently executing HTTP handler ceiling.
     #[serde(default = "default_web_max_http_handlers")]
     pub max_http_handlers: usize,
+    /// Process-wide transient WebSocket byte sub-budget inside pending bytes.
+    #[serde(default = "default_web_websocket_bytes_global")]
+    pub websocket_bytes_global: usize,
+    /// WebSocket usage percentage above which ordinary admission uses replacement.
+    #[serde(default = "default_web_websocket_admission_watermark_pct")]
+    pub websocket_admission_watermark_pct: u8,
+    /// WebSocket usage percentage that triggers pressure eviction.
+    #[serde(default = "default_web_websocket_eviction_watermark_pct")]
+    pub websocket_eviction_watermark_pct: u8,
+    /// Accepted HTTP connections that WebSocket upgrades must leave available.
+    #[serde(default = "default_web_websocket_http_connection_reserve")]
+    pub websocket_http_connection_reserve: usize,
     /// Process-wide concurrently collected request body ceiling.
     #[serde(default = "default_web_max_body_readers")]
     pub max_body_readers: usize,
@@ -216,6 +249,10 @@ impl Default for WebLimitsConfig {
             max_frames_per_body: default_web_max_frames_per_body(),
             max_http_connections: default_web_max_http_connections(),
             max_http_handlers: default_web_max_http_handlers(),
+            websocket_bytes_global: default_web_websocket_bytes_global(),
+            websocket_admission_watermark_pct: default_web_websocket_admission_watermark_pct(),
+            websocket_eviction_watermark_pct: default_web_websocket_eviction_watermark_pct(),
+            websocket_http_connection_reserve: default_web_websocket_http_connection_reserve(),
             max_body_readers: default_web_max_body_readers(),
             max_body_bytes_global: default_web_max_body_bytes_global(),
             max_sessions_global: default_web_max_sessions_global(),
@@ -265,6 +302,15 @@ pub struct WebTimeoutsConfig {
     /// Maximum wait for one empty downlink long poll.
     #[serde(default = "default_web_long_poll_timeout_secs")]
     pub long_poll_secs: u64,
+    /// Maximum wait for one WebSocket write to complete.
+    #[serde(default = "default_web_websocket_write_secs")]
+    pub websocket_write_secs: u64,
+    /// Maximum wait for WebSocket queue or byte-budget progress.
+    #[serde(default = "default_web_websocket_backpressure_secs")]
+    pub websocket_backpressure_secs: u64,
+    /// Maximum graceful close wait for an evicted WebSocket.
+    #[serde(default = "default_web_websocket_eviction_secs")]
+    pub websocket_eviction_secs: u64,
     /// Lifetime of an unused bootstrap credential and closed-token replay marker.
     #[serde(default = "default_web_bootstrap_lifetime_secs")]
     pub bootstrap_lifetime_secs: u64,
@@ -289,6 +335,9 @@ impl Default for WebTimeoutsConfig {
             body_secs: default_web_body_timeout_secs(),
             stream_handshake_secs: default_web_stream_handshake_timeout_secs(),
             long_poll_secs: default_web_long_poll_timeout_secs(),
+            websocket_write_secs: default_web_websocket_write_secs(),
+            websocket_backpressure_secs: default_web_websocket_backpressure_secs(),
+            websocket_eviction_secs: default_web_websocket_eviction_secs(),
             bootstrap_lifetime_secs: default_web_bootstrap_lifetime_secs(),
             reconnect_grace_secs: default_web_reconnect_grace_secs(),
             http_idle_secs: default_web_http_idle_secs(),
@@ -418,6 +467,14 @@ macro_rules! u32_default {
     };
 }
 
+macro_rules! u8_default {
+    ($name:ident, $value:expr) => {
+        fn $name() -> u8 {
+            $value
+        }
+    };
+}
+
 macro_rules! u64_default {
     ($name:ident, $value:expr) => {
         fn $name() -> u64 {
@@ -433,6 +490,10 @@ usize_default!(default_web_carrier_batch_bytes, 2 * 1024 * 1024);
 usize_default!(default_web_max_frames_per_body, 4096);
 usize_default!(default_web_max_http_connections, 1024);
 usize_default!(default_web_max_http_handlers, 512);
+usize_default!(default_web_websocket_bytes_global, 256 * 1024 * 1024);
+u8_default!(default_web_websocket_admission_watermark_pct, 75);
+u8_default!(default_web_websocket_eviction_watermark_pct, 90);
+usize_default!(default_web_websocket_http_connection_reserve, 64);
 usize_default!(default_web_max_body_readers, 32);
 usize_default!(default_web_max_body_bytes_global, 64 * 1024 * 1024);
 usize_default!(default_web_max_sessions_global, 128);
@@ -467,6 +528,9 @@ u64_default!(default_web_header_timeout_secs, 10);
 u64_default!(default_web_body_timeout_secs, 30);
 u64_default!(default_web_stream_handshake_timeout_secs, 10);
 u64_default!(default_web_long_poll_timeout_secs, 25);
+u64_default!(default_web_websocket_write_secs, 30);
+u64_default!(default_web_websocket_backpressure_secs, 30);
+u64_default!(default_web_websocket_eviction_secs, 1);
 u64_default!(default_web_bootstrap_lifetime_secs, 120);
 u64_default!(default_web_reconnect_grace_secs, 120);
 u64_default!(default_web_http_idle_secs, 75);
diff --git a/src/config/types/web_debug.rs b/src/config/types/web_debug.rs
index 3c8cccc..4bc0df9 100644
--- a/src/config/types/web_debug.rs
+++ b/src/config/types/web_debug.rs
@@ -90,10 +90,7 @@ fn default_max_window_secs() -> u64 {
 }
 
 /// Checks whether a hot debug policy fits restart-frozen process capacities.
-pub(crate) fn web_debug_fits_limits(
-    policy: &WebDebugConfig,
-    limits: &WebLimitsConfig,
-) -> bool {
+pub(crate) fn web_debug_fits_limits(policy: &WebDebugConfig, limits: &WebLimitsConfig) -> bool {
     policy.body_prefix_bytes <= limits.max_body_bytes
         && policy.body_prefix_bytes <= limits.debug_bytes_global
         && policy.decoy_body_prefix_bytes <= limits.debug_bytes_global
diff --git a/src/maestro/generation.rs b/src/maestro/generation.rs
index 8a8c5de..a81c786 100644
--- a/src/maestro/generation.rs
+++ b/src/maestro/generation.rs
@@ -246,11 +246,19 @@ impl RuntimeGeneration {
 
     /// Registers a session only while admission remains open.
     pub(crate) fn spawn_session<F>(&self, future: F) -> bool
+    where
+        F: Future<Output = ()> + Send + 'static,
+    {
+        self.try_spawn_session(future).is_ok()
+    }
+
+    /// Registers one session or returns its unpolled future to the caller.
+    pub(crate) fn try_spawn_session<F>(&self, future: F) -> Result<(), F>
     where
         F: Future<Output = ()> + Send + 'static,
     {
         let Some(_registration) = self.session_admission.try_register() else {
-            return false;
+            return Err(future);
         };
         let cancel = self.session_cancel.clone();
         self.sessions.spawn(async move {
@@ -259,7 +267,7 @@ impl RuntimeGeneration {
                 _ = future => {}
             }
         });
-        true
+        Ok(())
     }
 
     /// Closes admission while preserving already registered sessions.
diff --git a/src/maestro/orchestrator.rs b/src/maestro/orchestrator.rs
index b065088..387a299 100644
--- a/src/maestro/orchestrator.rs
+++ b/src/maestro/orchestrator.rs
@@ -318,11 +318,8 @@ pub(super) async fn run_telemt_core(
     active_runtime_tx.send_replace(Some(active_runtime.clone()));
     runtime_tasks::mark_runtime_ready(&startup_tracker).await;
 
-    let listener_manager = listeners::ListenerManager::start(
-        bound,
-        active_runtime.clone(),
-        web_trace.clone(),
-    );
+    let listener_manager =
+        listeners::ListenerManager::start(bound, active_runtime.clone(), web_trace.clone());
     let reload_supervisor = reload_supervisor::ReloadSupervisor::spawn(
         active_runtime.clone(),
         reload_control,
diff --git a/src/transport/middle_proxy/tests/send_adversarial_tests.rs b/src/transport/middle_proxy/tests/send_adversarial_tests.rs
index eac095f..7ccd62d 100644
--- a/src/transport/middle_proxy/tests/send_adversarial_tests.rs
+++ b/src/transport/middle_proxy/tests/send_adversarial_tests.rs
@@ -18,9 +18,7 @@ async fn make_pool() -> (Arc<MePool>, Arc<SecureRandom>) {
     make_pool_with_decision(NetworkDecision::default()).await
 }
 
-async fn make_pool_with_decision(
-    decision: NetworkDecision,
-) -> (Arc<MePool>, Arc<SecureRandom>) {
+async fn make_pool_with_decision(decision: NetworkDecision) -> (Arc<MePool>, Arc<SecureRandom>) {
     let general = GeneralConfig {
         me_route_no_writer_mode: MeRouteNoWriterMode::AsyncRecoveryFailfast,
         me_route_no_writer_wait_ms: 50,
diff --git a/src/web/bridge.rs b/src/web/bridge.rs
index fce1113..67a1b57 100644
--- a/src/web/bridge.rs
+++ b/src/web/bridge.rs
@@ -59,18 +59,20 @@ const batchLimit=__BATCH_LIMIT__,queueLimit=__QUEUE_LIMIT__,queueItemLimit=__QUE
 const laneQueueLimit=Math.min(queueLimit,8388608),laneItemLimit=Math.min(queueItemLimit,1024),closedLaneLimit=4096;
 const fragment=location.hash,androidNonce=/^#android=([A-Za-z0-9_-]{43})$/.exec(fragment)?.[1]||'';
 history.replaceState(null,'',location.pathname);
-let initialized=false,closed=false,port=null,sessionToken='',createStarted=false;
+let initialized=false,closed=false,port=null,sessionToken='',createStarted=false,socket=null,socketReady=false;
 let queuedBytes=0,queuedItems=0,upSequence=1,downCursor='0',upRunning=false,pollController=null;
 const pending=[],upPending=[],lanes=new Map(),closedLanes=new Set(),closedLaneOrder=[];
 const status=state=>{if(port&&!closed)port.postMessage({t:'status',state})};
 const pause=milliseconds=>new Promise(resolve=>setTimeout(resolve,milliseconds));
+const socketURL=()=>relayOrigin.replace(/^https:/,'wss:')+'/api/v1/ws';
 const options=(method,token,body,headers,signal,keepalive)=>({
  method,body,signal,keepalive:!!keepalive,mode:'same-origin',credentials:'omit',cache:'no-store',redirect:'error',referrerPolicy:'no-referrer',
  headers:Object.assign(token?{Authorization:'Bearer '+token}:{},body?{'Content-Type':'application/octet-stream'}:{},headers||{})
 });
 function reserve(data,lane){
- if(!data.byteLength||data.byteLength>queueLimit-queuedBytes||queuedItems>=queueItemLimit)return false;
- if(lane&&(data.byteLength>laneQueueLimit-lane.bytes||lane.items>=laneItemLimit))return false;
+ let buffered=socket?socket.bufferedAmount:0;for(const value of lanes.values())if(value.socket)buffered+=value.socket.bufferedAmount;
+ if(!data.byteLength||data.byteLength>queueLimit-queuedBytes-buffered||queuedItems>=queueItemLimit)return false;
+ if(lane&&(data.byteLength>laneQueueLimit-lane.bytes-(lane.socket?lane.socket.bufferedAmount:0)||lane.items>=laneItemLimit))return false;
  queuedBytes+=data.byteLength;queuedItems++;if(lane){lane.bytes+=data.byteLength;lane.items++}return true;
 }
 function release(bytes,items,lane){queuedBytes-=bytes;queuedItems-=items;if(lane){lane.bytes-=bytes;lane.items-=items}}
@@ -154,12 +156,17 @@ async function createSession(first){
   const welcome=await response.arrayBuffer();
   port.postMessage(welcome,[welcome]);status('connected');
   if(carrier==='https-lanes')ensureLane(0);
+  if(carrier==='websocket')openSocket();
   for(const data of pending.splice(0)){release(data.byteLength,1,null);queueCarrier(data)}
-  if(carrier==='https')poll();else pollLane(lanes.get(0));
+  if(carrier==='https')poll();else if(carrier==='https-lanes')pollLane(lanes.get(0));
  }catch(error){fail()}
 }
 function queueCarrier(data){
- try{if(carrier==='https')queueUp(data);else for(const value of splitFrames(data))queueLane(value)}catch(error){fail()}
+ try{
+  if(carrier==='https')queueUp(data);
+  else if(carrier==='websocket')queueSocket(data);
+  else for(const value of splitFrames(data))queueLane(value);
+ }catch(error){fail()}
 }
 function queueUp(data){if(!reserve(data,null)){fail();return}upPending.push(data);runUp()}
 async function runUp(){
@@ -174,6 +181,31 @@ async function runUp(){
  }catch(error){fail()}
  finally{upRunning=false;if(!closed&&sessionToken&&upPending.length)runUp()}
 }
+function openSocket(){
+ if(socket||closed)return;socket=new WebSocket(socketURL(),'tproxy-v1.'+sessionToken);socket.binaryType='arraybuffer';
+ socket.onopen=()=>{if(closed)return;socketReady=true;status('connected');runSocketUp()};
+ socket.onmessage=event=>{
+  if(closed||!(event.data instanceof ArrayBuffer)){fail();return}
+  try{const bound=frameBound(event.data,4096,batchLimit);if(bound.bytes!==event.data.byteLength)throw new Error('invalid frame batch')}catch(error){fail();return}
+  port.postMessage({t:'traffic',up:0,down:event.data.byteLength});port.postMessage(event.data,[event.data]);status('connected');
+ };
+ socket.onerror=()=>{};socket.onclose=()=>{socketReady=false;if(!closed)fail()};
+}
+function queueSocket(data){if(!reserve(data,null)){fail();return}upPending.push(data);runSocketUp()}
+async function waitSocket(next,size,limit){
+ while(!closed&&next.readyState===WebSocket.OPEN&&next.bufferedAmount>limit-size)await pause(10);
+ if(closed||next.readyState!==WebSocket.OPEN)throw new Error('websocket closed');
+}
+async function runSocketUp(){
+ if(upRunning||!socketReady)return;upRunning=true;
+ try{
+  while(!closed&&socketReady&&upPending.length){
+   const batch=joinPending(upPending,null);await waitSocket(socket,batch.total,queueLimit);socket.send(batch.body);
+   release(batch.total,batch.count,null);port.postMessage({t:'traffic',up:batch.total,down:0});
+  }
+ }catch(error){if(!closed)fail()}
+ finally{upRunning=false;if(!closed&&socketReady&&upPending.length)runSocketUp()}
+}
 async function poll(){
  while(!closed&&sessionToken){
   try{
@@ -190,7 +222,7 @@ async function poll(){
 }
 function ensureLane(id){
  let lane=lanes.get(id);
- if(!lane){lane={id,sequence:1,cursor:'0',pending:[],bytes:0,items:0,running:false,polling:false,controller:null};lanes.set(id,lane)}
+ if(!lane){lane={id,sequence:1,cursor:'0',pending:[],bytes:0,items:0,running:false,polling:false,controller:null,socket:null,ready:false,remoteClosed:false};lanes.set(id,lane)}
  return lane;
 }
 function rememberLaneClosed(id){
@@ -198,10 +230,13 @@ function rememberLaneClosed(id){
  if(closedLaneOrder.length===closedLaneLimit)closedLanes.delete(closedLaneOrder.shift());
  closedLanes.add(id);closedLaneOrder.push(id);
 }
-function finishLane(lane){
+function closeFrame(id){const value=new Uint8Array(8);value[0]=3;value[1]=(id>>>16)&255;value[2]=(id>>>8)&255;value[3]=id&255;return value.buffer}
+function finishLane(lane,notifyClient){
  if(lanes.get(lane.id)!==lane)return;
+ if(lane.socket&&lane.socket.readyState<WebSocket.CLOSING)lane.socket.close();
  if(lane.bytes||lane.items)release(lane.bytes,lane.items,lane);
  lane.pending.length=0;lanes.delete(lane.id);rememberLaneClosed(lane.id);
+ if(notifyClient&&!lane.remoteClosed&&port){const frame=closeFrame(lane.id);port.postMessage(frame,[frame])}
 }
 function queueLane(value){
  let lane=lanes.get(value.id);
@@ -210,7 +245,29 @@ function queueLane(value){
  if(!lane&&value.type!==1)throw new Error('lane did not begin with OPEN');
  lane=lane||ensureLane(value.id);
  if(!reserve(value.data,lane)){fail();return}
- lane.pending.push(value.data);runLaneUp(lane);
+ lane.pending.push(value.data);
+ if(carrier==='websocket-lanes'){openLaneSocket(lane);runLaneSocketUp(lane)}else runLaneUp(lane);
+}
+function openLaneSocket(lane){
+ if(lane.socket||closed)return;lane.socket=new WebSocket(socketURL(),'tproxy-lane-v1.'+sessionToken+'.'+String(lane.id));lane.socket.binaryType='arraybuffer';
+ lane.socket.onopen=()=>{if(closed||lanes.get(lane.id)!==lane)return;lane.ready=true;status('connected');runLaneSocketUp(lane)};
+ lane.socket.onmessage=event=>{
+  if(closed||lanes.get(lane.id)!==lane||!(event.data instanceof ArrayBuffer)){finishLane(lane,true);return}
+  let values;try{values=splitFrames(event.data);for(const value of values)if(value.id!==lane.id)throw new Error('cross-lane frame')}catch(error){finishLane(lane,true);return}
+  if(values.some(value=>value.type===3))lane.remoteClosed=true;
+  port.postMessage({t:'traffic',up:0,down:event.data.byteLength});port.postMessage(event.data,[event.data]);status('connected');
+ };
+ lane.socket.onerror=()=>{};lane.socket.onclose=()=>{lane.ready=false;lane.socket=null;if(!closed)finishLane(lane,true)};
+}
+async function runLaneSocketUp(lane){
+ if(lane.running||!lane.ready)return;lane.running=true;
+ try{
+  while(!closed&&lane.ready&&lanes.get(lane.id)===lane&&lane.pending.length){
+   const batch=joinPending(lane.pending,lane);await waitSocket(lane.socket,batch.total,laneQueueLimit);lane.socket.send(batch.body);
+   release(batch.total,batch.count,lane);port.postMessage({t:'traffic',up:batch.total,down:0});
+  }
+ }catch(error){if(!closed)finishLane(lane,true)}
+ finally{lane.running=false;if(!closed&&lane.ready&&lane.pending.length)runLaneSocketUp(lane)}
 }
 async function runLaneUp(lane){
  if(lane.running)return;lane.running=true;
@@ -232,7 +289,7 @@ async function pollLane(lane){
    const controller=new AbortController(),laneID=String(lane.id);lane.controller=controller;
    const response=await request('/api/v1/down',()=>options('POST',sessionToken,null,{'X-Down-Cursor':lane.cursor,'X-Lane-ID':laneID},controller.signal));
    if(response.status===204){
-    if(response.headers.get('X-Lane-Closed')==='1'){finishLane(lane);return}
+    if(response.headers.get('X-Lane-Closed')==='1'){finishLane(lane,false);return}
     status('connected');continue;
    }
    if(response.status!==200)throw new Error('lane downlink rejected');
@@ -250,7 +307,7 @@ function deleteSession(){
 }
 function close(notifyServer){
  if(closed)return;closed=true;if(pollController)pollController.abort();
- for(const lane of lanes.values())if(lane.controller)lane.controller.abort();
+ if(socket)socket.close();for(const lane of lanes.values()){if(lane.controller)lane.controller.abort();if(lane.socket)lane.socket.close()}
  if(notifyServer)deleteSession();pending.length=0;upPending.length=0;
  for(const lane of lanes.values())lane.pending.length=0;lanes.clear();queuedBytes=0;queuedItems=0;if(port)port.close();
 }
@@ -357,4 +414,45 @@ mod tests {
             "the iOS native carrier cannot parse a comma-declared single-quoted bootstrap"
         );
     }
+
+    #[test]
+    fn rendered_page_advertises_exact_websocket_carriers() {
+        let websocket = render(
+            "proxy.example.com",
+            "CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC",
+            2 * 1024 * 1024,
+            32 * 1024 * 1024,
+            16 * 1024,
+            WebCarrier::Websocket,
+            &SecureRandom::new(),
+        );
+        assert!(websocket.body.contains("carrier='websocket'"));
+        assert!(
+            websocket
+                .body
+                .contains("new WebSocket(socketURL(),'tproxy-v1.'+sessionToken)")
+        );
+        assert!(
+            websocket
+                .content_security_policy
+                .contains("connect-src 'self' wss://proxy.example.com")
+        );
+
+        let lanes = render(
+            "proxy.example.com",
+            "DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD",
+            2 * 1024 * 1024,
+            32 * 1024 * 1024,
+            16 * 1024,
+            WebCarrier::WebsocketLanes,
+            &SecureRandom::new(),
+        );
+        assert!(lanes.body.contains("carrier='websocket-lanes'"));
+        assert!(
+            lanes
+                .body
+                .contains("'tproxy-lane-v1.'+sessionToken+'.'+String(lane.id)")
+        );
+        assert!(!lanes.body.contains("__"));
+    }
 }
diff --git a/src/web/http.rs b/src/web/http.rs
index 56f46cc..47f1d23 100644
--- a/src/web/http.rs
+++ b/src/web/http.rs
@@ -5,8 +5,8 @@ use std::sync::Arc;
 use std::time::{Duration, Instant};
 
 use bytes::Bytes;
-use http_body_util::combinators::UnsyncBoxBody;
 use http_body_util::BodyExt;
+use http_body_util::combinators::UnsyncBoxBody;
 use hyper::header::{self, HeaderName, HeaderValue};
 use hyper::server::conn::http1;
 use hyper::service::service_fn;
@@ -34,13 +34,16 @@ mod down;
 mod request;
 // Carrier response construction and lane-header helpers are shared by handlers.
 mod response;
+// RFC 6455 upgrade validation and carrier drivers remain isolated from HTTP routing.
 #[cfg(test)]
 mod tests;
+mod websocket;
 // Enabled-debug integration coverage remains separate from carrier behavior tests.
 #[cfg(test)]
 #[path = "http/trace_tests.rs"]
 mod trace_tests;
 
+use crate::web::trace::{HttpTraceExchange, TraceDirection, TraceLifecycleEvent, TraceRoute};
 use activity::{ActivityBody, RequestActivity};
 use body::{CollectBodyError, CollectedBody, RequestBody, collect_body};
 use decoy::serve_decoy;
@@ -53,9 +56,6 @@ use response::{
     bad_gateway, carrier_empty, carrier_headers, carrier_lane, full_response, generic_not_found,
     insert_header, service_unavailable,
 };
-use crate::web::trace::{
-    HttpTraceExchange, TraceDirection, TraceLifecycleEvent, TraceRoute,
-};
 
 type BoxError = Box<dyn Error + Send + Sync>;
 type HttpBody = UnsyncBoxBody<Bytes, BoxError>;
@@ -63,6 +63,7 @@ type HttpResponse = Response<HttpBody>;
 
 const CREATE_BODY_LIMIT: usize = 64;
 const TRANSPORT_PATHS: [&str; 3] = ["/api/v1/session", "/api/v1/up", "/api/v1/down"];
+const WEBSOCKET_PATH: &str = "/api/v1/ws";
 
 /// Serves one bounded HTTP/1.1 connection accepted from an external TLS terminator.
 pub(crate) async fn serve_connection(
@@ -107,8 +108,8 @@ pub(crate) async fn serve_connection(
             if let Some(trace) = &trace {
                 trace.response_ready(&response);
             }
-            let response = response
-                .map(|body| ActivityBody::new(body, activity, trace).boxed_unsync());
+            let response =
+                response.map(|body| ActivityBody::new(body, activity, trace).boxed_unsync());
             Ok::<_, Infallible>(response)
         }
     });
@@ -117,7 +118,11 @@ pub(crate) async fn serve_connection(
         .header_read_timeout(header_timeout)
         .max_buf_size(max_header_bytes)
         .keep_alive(true)
-        .serve_connection(TokioIo::new(stream), service);
+        .serve_connection(
+            TokioIo::new(websocket::ConnectionIo::new(stream, connection_permit)),
+            service,
+        )
+        .with_upgrades();
     tokio::pin!(connection);
     let mut idle_check = tokio::time::interval((idle_timeout / 2).max(Duration::from_secs(1)));
     idle_check.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Skip);
@@ -135,7 +140,6 @@ pub(crate) async fn serve_connection(
             }
         }
     }
-    drop(connection_permit);
 }
 
 async fn handle_request(
@@ -163,6 +167,17 @@ async fn handle_request(
         return generic_not_found();
     };
     let path = request.uri().path();
+    if path == WEBSOCKET_PATH {
+        return websocket::handle(
+            request,
+            peer,
+            client_ip_source,
+            trusted_proxy_cidrs,
+            runtime,
+            vhost,
+        )
+        .await;
+    }
     if TRANSPORT_PATHS.contains(&path) {
         return handle_api(
             request,
@@ -394,7 +409,9 @@ async fn handle_session(
             );
             response
         }
-        Err(error @ (ManagerError::Limit | ManagerError::Backpressure | ManagerError::Concurrent)) => {
+        Err(
+            error @ (ManagerError::Limit | ManagerError::Backpressure | ManagerError::Concurrent),
+        ) => {
             runtime.trace().record_profile_lifecycle(
                 client_ip,
                 Some(trace_session_id),
@@ -435,6 +452,9 @@ async fn handle_up(
     let Ok(session) = runtime.get_session(token_hash, &vhost.host) else {
         return serve_decoy(request, vhost, true, &runtime).await;
     };
+    if session.carrier().uses_websocket() {
+        return serve_decoy(request, vhost, true, &runtime).await;
+    }
     if let Some(trace) = request_trace(&request) {
         trace.set_route(TraceRoute::Uplink);
         trace.bind_identity(session.trace_identity());
diff --git a/src/web/http/body.rs b/src/web/http/body.rs
index d371c51..7550cda 100644
--- a/src/web/http/body.rs
+++ b/src/web/http/body.rs
@@ -9,9 +9,7 @@ use hyper::Request;
 use hyper::body::{Body, Frame, Incoming, SizeHint};
 
 use crate::web::manager::WebProcessRuntime;
-use crate::web::trace::{
-    HttpTraceExchange, TraceBodyState, TraceDirection,
-};
+use crate::web::trace::{HttpTraceExchange, TraceBodyState, TraceDirection};
 
 /// Incoming request body wrapper that observes frames without changing streaming semantics.
 pub(super) struct RequestBody {
@@ -30,6 +28,15 @@ impl RequestBody {
         }
     }
 
+    /// Completes observation for a request whose Hyper body is already empty.
+    pub(super) fn finish_empty(&mut self) -> bool {
+        if !self.inner.is_end_stream() {
+            return false;
+        }
+        self.finish(TraceBodyState::Complete);
+        true
+    }
+
     fn finish(&mut self, state: TraceBodyState) {
         if self.terminal {
             return;
diff --git a/src/web/http/decoy.rs b/src/web/http/decoy.rs
index 873a4af..b868e21 100644
--- a/src/web/http/decoy.rs
+++ b/src/web/http/decoy.rs
@@ -236,6 +236,7 @@ fn sanitize_transport_request<B>(request: &mut Request<B>) {
         header::CONTENT_TYPE,
         header::UPGRADE,
         HeaderName::from_static("sec-websocket-key"),
+        HeaderName::from_static("sec-websocket-extensions"),
         HeaderName::from_static("sec-websocket-protocol"),
         HeaderName::from_static("sec-websocket-version"),
         HeaderName::from_static("x-down-cursor"),
diff --git a/src/web/http/down.rs b/src/web/http/down.rs
index 4b5dfb3..e24a125 100644
--- a/src/web/http/down.rs
+++ b/src/web/http/down.rs
@@ -32,6 +32,9 @@ pub(super) async fn handle_down(
     let Ok(session) = runtime.get_session(token_hash, &vhost.host) else {
         return serve_decoy(request, vhost, true, &runtime).await;
     };
+    if session.carrier().uses_websocket() {
+        return serve_decoy(request, vhost, true, &runtime).await;
+    }
     if let Some(trace) = request_trace(&request) {
         trace.set_route(TraceRoute::Downlink);
         trace.bind_identity(session.trace_identity());
diff --git a/src/web/http/response.rs b/src/web/http/response.rs
index e025e84..731c85c 100644
--- a/src/web/http/response.rs
+++ b/src/web/http/response.rs
@@ -9,16 +9,14 @@ use crate::config::WebCarrier;
 use crate::web::frame;
 
 /// Validates and resolves the optional carrier lane header.
-pub(super) fn carrier_lane<B>(
-    request: &Request<B>,
-    carrier: WebCarrier,
-) -> Option<Option<u32>> {
+pub(super) fn carrier_lane<B>(request: &Request<B>, carrier: WebCarrier) -> Option<Option<u32>> {
     match carrier {
         WebCarrier::Https => (!request.headers().contains_key("x-lane-id")).then_some(None),
         WebCarrier::HttpsLanes => canonical_u64_header(request, "x-lane-id")
             .and_then(|value| u32::try_from(value).ok())
             .filter(|value| *value <= frame::MAX_STREAM_ID)
             .map(Some),
+        WebCarrier::Websocket | WebCarrier::WebsocketLanes => None,
     }
 }
 
diff --git a/src/web/http/tests.rs b/src/web/http/tests.rs
index bde0adc..bc90493 100644
--- a/src/web/http/tests.rs
+++ b/src/web/http/tests.rs
@@ -232,7 +232,10 @@ async fn rejected_bridge_bootstrap_falls_back_to_uncacheable_static_index() {
     let fallback_response = request(&listener, &runtime, bridge_request()).await;
     let (fallback_headers, fallback_body) = split_response(&fallback_response);
     assert!(fallback_headers.starts_with(b"HTTP/1.1 200"));
-    assert_eq!(response_header(fallback_headers, "cache-control"), "no-store");
+    assert_eq!(
+        response_header(fallback_headers, "cache-control"),
+        "no-store"
+    );
     assert_eq!(fallback_body, b"<!doctype html><title>decoy</title>");
 
     runtime.shutdown().await;
diff --git a/src/web/http/websocket.rs b/src/web/http/websocket.rs
new file mode 100644
index 0000000..c448127
--- /dev/null
+++ b/src/web/http/websocket.rs
@@ -0,0 +1,461 @@
+use std::net::SocketAddr;
+use std::pin::Pin;
+use std::sync::Arc;
+use std::task::{Context, Poll};
+use std::time::Duration;
+
+use base64::Engine as _;
+use bytes::Bytes;
+use hyper::header::{self, HeaderName, HeaderValue};
+use hyper::{Method, Request, StatusCode};
+use ipnetwork::IpNetwork;
+use sha1::{Digest as _, Sha1};
+use sha2::Sha256;
+use tokio::io::{AsyncRead, AsyncWrite, ReadBuf};
+use tokio::net::TcpStream;
+use tokio::sync::OwnedSemaphorePermit;
+
+use super::body::RequestBody;
+use super::decoy::serve_decoy;
+use super::request::client_ip;
+use super::response::{full_response, insert_header};
+use super::{HttpResponse, request_trace, set_trace_route};
+use crate::config::{WebCarrier, WebClientIpSource, WebRuntimeVhost};
+use crate::web::manager::{TokenHash, WebProcessRuntime, WebSocketKind};
+use crate::web::trace::TraceRoute;
+
+// Codec buffers and fixed driver state are charged before HTTP 101 commits.
+const BASE_BUDGET_BYTES: usize = 132 * 1024;
+const WEBSOCKET_GUID: &[u8] = b"258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
+
+/// Accepted connection IO retains the process HTTP slot after an upgrade.
+pub(super) struct ConnectionIo {
+    stream: TcpStream,
+    _connection_permit: OwnedSemaphorePermit,
+    websocket_read: Option<WebSocketReadBoundary>,
+}
+
+impl ConnectionIo {
+    pub(super) fn new(stream: TcpStream, connection_permit: OwnedSemaphorePermit) -> Self {
+        Self {
+            stream,
+            _connection_permit: connection_permit,
+            websocket_read: None,
+        }
+    }
+
+    async fn readable(&self) -> std::io::Result<()> {
+        if self
+            .websocket_read
+            .as_ref()
+            .is_some_and(WebSocketReadBoundary::has_buffered)
+        {
+            return Ok(());
+        }
+        self.stream.readable().await
+    }
+
+    fn enable_websocket(&mut self, buffered: Bytes) {
+        self.websocket_read = Some(WebSocketReadBoundary::new(buffered));
+    }
+
+    fn websocket_fragmented_message(&self) -> bool {
+        self.websocket_read
+            .as_ref()
+            .is_some_and(WebSocketReadBoundary::fragmented_message)
+    }
+}
+
+// Frame-boundary reads keep the kernel readiness gate authoritative even when
+// Hyper read-ahead or one TCP packet contains several WebSocket messages.
+enum WebSocketReadState {
+    Header {
+        bytes: [u8; 14],
+        filled: usize,
+        target: usize,
+    },
+    Payload {
+        remaining: usize,
+    },
+}
+
+struct WebSocketReadBoundary {
+    buffered: Bytes,
+    state: WebSocketReadState,
+    fragmented_message: bool,
+}
+
+impl WebSocketReadBoundary {
+    fn new(buffered: Bytes) -> Self {
+        Self {
+            buffered,
+            state: Self::new_header(),
+            fragmented_message: false,
+        }
+    }
+
+    fn has_buffered(&self) -> bool {
+        !self.buffered.is_empty()
+    }
+
+    fn fragmented_message(&self) -> bool {
+        self.fragmented_message
+    }
+
+    fn maximum_read(&self, requested: usize) -> usize {
+        let boundary = match self.state {
+            WebSocketReadState::Header { filled, target, .. } => target.saturating_sub(filled),
+            WebSocketReadState::Payload { remaining } => remaining,
+        };
+        requested.min(boundary)
+    }
+
+    fn observe(&mut self, bytes: &[u8]) {
+        match &mut self.state {
+            WebSocketReadState::Header {
+                bytes: header,
+                filled,
+                target,
+            } => {
+                debug_assert!(bytes.len() <= target.saturating_sub(*filled));
+                header[*filled..*filled + bytes.len()].copy_from_slice(bytes);
+                *filled += bytes.len();
+                if *filled == 2 && *target == 2 {
+                    let extended = match header[1] & 0x7f {
+                        126 => 2,
+                        127 => 8,
+                        _ => 0,
+                    };
+                    let mask = usize::from(header[1] & 0x80 != 0) * 4;
+                    *target = 2 + extended + mask;
+                }
+                if *filled == *target {
+                    let finished = header[0] & 0x80 != 0;
+                    match header[0] & 0x0f {
+                        0 if finished => self.fragmented_message = false,
+                        1 | 2 if !finished => self.fragmented_message = true,
+                        _ => {}
+                    }
+                    let payload = match header[1] & 0x7f {
+                        value @ 0..=125 => usize::from(value),
+                        126 => usize::from(u16::from_be_bytes([header[2], header[3]])),
+                        127 => usize::try_from(u64::from_be_bytes([
+                            header[2], header[3], header[4], header[5], header[6], header[7],
+                            header[8], header[9],
+                        ]))
+                        .unwrap_or(usize::MAX),
+                        _ => unreachable!(),
+                    };
+                    self.state = if payload == 0 {
+                        Self::new_header()
+                    } else {
+                        WebSocketReadState::Payload { remaining: payload }
+                    };
+                }
+            }
+            WebSocketReadState::Payload { remaining } => {
+                debug_assert!(bytes.len() <= *remaining);
+                *remaining -= bytes.len();
+                if *remaining == 0 {
+                    self.state = Self::new_header();
+                }
+            }
+        }
+    }
+
+    fn new_header() -> WebSocketReadState {
+        WebSocketReadState::Header {
+            bytes: [0; 14],
+            filled: 0,
+            target: 2,
+        }
+    }
+}
+
+impl AsyncRead for ConnectionIo {
+    fn poll_read(
+        self: Pin<&mut Self>,
+        context: &mut Context<'_>,
+        buffer: &mut ReadBuf<'_>,
+    ) -> Poll<std::io::Result<()>> {
+        let this = self.get_mut();
+        let Some(boundary) = this.websocket_read.as_mut() else {
+            return Pin::new(&mut this.stream).poll_read(context, buffer);
+        };
+        let maximum = boundary.maximum_read(buffer.remaining());
+        if maximum == 0 {
+            return Poll::Ready(Ok(()));
+        }
+        if !boundary.buffered.is_empty() {
+            let bytes = boundary
+                .buffered
+                .split_to(maximum.min(boundary.buffered.len()));
+            boundary.observe(&bytes);
+            buffer.put_slice(&bytes);
+            return Poll::Ready(Ok(()));
+        }
+        let unfilled = buffer.initialize_unfilled_to(maximum);
+        let mut limited = ReadBuf::new(unfilled);
+        match Pin::new(&mut this.stream).poll_read(context, &mut limited) {
+            Poll::Ready(Ok(())) => {
+                let filled = limited.filled().len();
+                boundary.observe(limited.filled());
+                drop(limited);
+                buffer.advance(filled);
+                Poll::Ready(Ok(()))
+            }
+            Poll::Ready(Err(error)) => Poll::Ready(Err(error)),
+            Poll::Pending => Poll::Pending,
+        }
+    }
+}
+
+impl AsyncWrite for ConnectionIo {
+    fn poll_write(
+        mut self: Pin<&mut Self>,
+        context: &mut Context<'_>,
+        bytes: &[u8],
+    ) -> Poll<std::io::Result<usize>> {
+        Pin::new(&mut self.stream).poll_write(context, bytes)
+    }
+
+    fn poll_flush(
+        mut self: Pin<&mut Self>,
+        context: &mut Context<'_>,
+    ) -> Poll<std::io::Result<()>> {
+        Pin::new(&mut self.stream).poll_flush(context)
+    }
+
+    fn poll_shutdown(
+        mut self: Pin<&mut Self>,
+        context: &mut Context<'_>,
+    ) -> Poll<std::io::Result<()>> {
+        Pin::new(&mut self.stream).poll_shutdown(context)
+    }
+}
+
+enum ParsedCarrier {
+    Multiplex,
+    Lane(u32),
+}
+
+struct ParsedUpgrade {
+    token_hash: TokenHash,
+    protocol: String,
+    accept: String,
+    carrier: ParsedCarrier,
+}
+
+pub(super) async fn handle(
+    mut request: Request<RequestBody>,
+    peer: SocketAddr,
+    client_ip_source: WebClientIpSource,
+    trusted_proxy_cidrs: &[IpNetwork],
+    runtime: Arc<WebProcessRuntime>,
+    vhost: Arc<WebRuntimeVhost>,
+) -> HttpResponse {
+    let Some(parsed) = parse_upgrade(&request) else {
+        return serve_decoy(request, vhost, true, &runtime).await;
+    };
+    if !request.body_mut().finish_empty() {
+        return serve_decoy(request, vhost, true, &runtime).await;
+    }
+    let Some(effective_ip) = client_ip(&request, peer, client_ip_source, trusted_proxy_cidrs)
+    else {
+        return serve_decoy(request, vhost, true, &runtime).await;
+    };
+    let Ok(session) = runtime.get_session(parsed.token_hash, &vhost.host) else {
+        return serve_decoy(request, vhost, true, &runtime).await;
+    };
+    let kind = match (parsed.carrier, session.carrier()) {
+        (ParsedCarrier::Multiplex, WebCarrier::Websocket) => WebSocketKind::Multiplex,
+        (ParsedCarrier::Lane(lane_id), WebCarrier::WebsocketLanes) => WebSocketKind::Lane(lane_id),
+        _ => return serve_decoy(request, vhost, true, &runtime).await,
+    };
+    let mut lane_reservation = match kind {
+        WebSocketKind::Multiplex => None,
+        WebSocketKind::Lane(lane_id) => match session.reserve_websocket_lane(lane_id) {
+            Ok(reservation) => Some(reservation),
+            Err(_) => return serve_decoy(request, vhost, true, &runtime).await,
+        },
+    };
+    let timeouts = runtime.active_generation().config().web.timeouts.clone();
+    let connection = match runtime
+        .admit_websocket(
+            session.profile_key(),
+            session.trace_session_id(),
+            effective_ip,
+            kind,
+            BASE_BUDGET_BYTES,
+            Duration::from_secs(timeouts.long_poll_secs),
+            Duration::from_secs(timeouts.websocket_eviction_secs),
+        )
+        .await
+    {
+        Ok(connection) => connection,
+        Err(_) => return serve_decoy(request, vhost, true, &runtime).await,
+    };
+    let trace_context = runtime.trace().websocket_context(
+        &request,
+        peer.ip(),
+        effective_ip,
+        connection.id(),
+        match kind {
+            WebSocketKind::Multiplex => None,
+            WebSocketKind::Lane(lane_id) => Some(lane_id),
+        },
+        || session.trace_identity(),
+    );
+    if let Some(trace) = request_trace(&request) {
+        trace.set_effective_ip(effective_ip);
+        trace.set_route(TraceRoute::Websocket);
+        trace.bind_identity(session.trace_identity());
+        trace.register_redaction(parsed.protocol.as_bytes());
+    }
+    let on_upgrade = hyper::upgrade::on(&mut request);
+    let protocol = parsed.protocol;
+    let accept = parsed.accept;
+    let driver_runtime = Arc::clone(&runtime);
+    let driver_session = Arc::clone(&session);
+    runtime.spawn_auxiliary(async move {
+        driver::run_upgraded(
+            on_upgrade,
+            driver_runtime,
+            driver_session,
+            connection,
+            lane_reservation.take(),
+            trace_context,
+        )
+        .await;
+    });
+    set_trace_route(&request, TraceRoute::Websocket);
+    let mut response = full_response(StatusCode::SWITCHING_PROTOCOLS, Bytes::new());
+    response.headers_mut().remove(header::CONTENT_LENGTH);
+    response
+        .headers_mut()
+        .insert(header::CONNECTION, HeaderValue::from_static("Upgrade"));
+    response
+        .headers_mut()
+        .insert(header::UPGRADE, HeaderValue::from_static("websocket"));
+    insert_header(
+        &mut response,
+        HeaderName::from_static("sec-websocket-accept"),
+        &accept,
+    );
+    insert_header(
+        &mut response,
+        HeaderName::from_static("sec-websocket-protocol"),
+        &protocol,
+    );
+    response
+}
+
+fn parse_upgrade<B>(request: &Request<B>) -> Option<ParsedUpgrade> {
+    if request.method() != Method::GET
+        || request.uri().query().is_some()
+        || request.headers().contains_key(header::AUTHORIZATION)
+        || request.headers().contains_key(header::CONTENT_LENGTH)
+        || request.headers().contains_key(header::TRANSFER_ENCODING)
+        || !single_header_eq(request, header::UPGRADE, "websocket")
+        || !single_header_eq(request, "sec-websocket-version", "13")
+        || !header_has_token(request, header::CONNECTION, "upgrade")
+    {
+        return None;
+    }
+    let key = single_header(request, "sec-websocket-key")?;
+    let decoded_key = base64::engine::general_purpose::STANDARD.decode(key).ok()?;
+    if decoded_key.len() != 16
+        || base64::engine::general_purpose::STANDARD.encode(&decoded_key) != key
+    {
+        return None;
+    }
+    let protocol = single_header(request, "sec-websocket-protocol")?;
+    if protocol
+        .bytes()
+        .any(|value| value == b',' || value.is_ascii_whitespace())
+    {
+        return None;
+    }
+    let (token, carrier) = if let Some(token) = protocol.strip_prefix("tproxy-v1.") {
+        (token, ParsedCarrier::Multiplex)
+    } else if let Some(lane) = protocol.strip_prefix("tproxy-lane-v1.") {
+        let (token, lane_id) = lane.split_once('.')?;
+        if lane_id.is_empty()
+            || lane_id.starts_with('+')
+            || (lane_id.len() > 1 && lane_id.starts_with('0'))
+        {
+            return None;
+        }
+        let lane_id = lane_id
+            .parse::<u32>()
+            .ok()
+            .filter(|value| (1..=crate::web::frame::MAX_STREAM_ID).contains(value))?;
+        (token, ParsedCarrier::Lane(lane_id))
+    } else {
+        return None;
+    };
+    let raw_token = base64::engine::general_purpose::URL_SAFE_NO_PAD
+        .decode(token)
+        .ok()?;
+    if raw_token.len() != 32
+        || token.len() != 43
+        || base64::engine::general_purpose::URL_SAFE_NO_PAD.encode(&raw_token) != token
+    {
+        return None;
+    }
+    let token_hash = Sha256::digest(&raw_token).into();
+    let mut accept = Sha1::new();
+    accept.update(key.as_bytes());
+    accept.update(WEBSOCKET_GUID);
+    Some(ParsedUpgrade {
+        token_hash,
+        protocol: protocol.to_string(),
+        accept: base64::engine::general_purpose::STANDARD.encode(accept.finalize()),
+        carrier,
+    })
+}
+
+fn single_header<'a, B>(
+    request: &'a Request<B>,
+    name: impl hyper::header::AsHeaderName,
+) -> Option<&'a str> {
+    let mut values = request.headers().get_all(name).iter();
+    let value = values.next()?.to_str().ok()?;
+    values.next().is_none().then_some(value)
+}
+
+fn single_header_eq<B>(
+    request: &Request<B>,
+    name: impl hyper::header::AsHeaderName,
+    expected: &str,
+) -> bool {
+    single_header(request, name).is_some_and(|value| value.eq_ignore_ascii_case(expected))
+}
+
+fn header_has_token<B>(
+    request: &Request<B>,
+    name: impl hyper::header::AsHeaderName,
+    expected: &str,
+) -> bool {
+    let mut found = false;
+    for value in request.headers().get_all(name) {
+        let Ok(value) = value.to_str() else {
+            return false;
+        };
+        for token in value.split(',').map(str::trim) {
+            if token.eq_ignore_ascii_case(expected) {
+                if found {
+                    return false;
+                }
+                found = true;
+            }
+        }
+    }
+    found
+}
+
+// Ordered WebSocket message relay and deadlines are isolated from handshake parsing.
+mod driver;
+
+#[cfg(test)]
+mod tests;
diff --git a/src/web/http/websocket/driver.rs b/src/web/http/websocket/driver.rs
new file mode 100644
index 0000000..bc71e21
--- /dev/null
+++ b/src/web/http/websocket/driver.rs
@@ -0,0 +1,638 @@
+use std::sync::Arc;
+use std::time::{Duration, Instant};
+
+use bytes::Bytes;
+use futures_util::{SinkExt, StreamExt};
+use hyper_util::rt::TokioIo;
+use tokio_tungstenite::WebSocketStream;
+use tokio_tungstenite::tungstenite::protocol::{Message, Role, WebSocketConfig};
+use tokio_util::sync::CancellationToken;
+
+use super::ConnectionIo;
+use crate::web::manager::{
+    ManagerError, WebProcessRuntime, WebSocketBudgetLease, WebSocketConnection,
+};
+use crate::web::session::{WebSession, WebSocketLaneReservation};
+use crate::web::trace::{TraceDirection, TraceWebSocketContext};
+
+const READ_BUFFER_BYTES: usize = 64 * 1024;
+const WRITE_BUFFER_BYTES: usize = 64 * 1024;
+
+pub(super) async fn run_upgraded(
+    on_upgrade: hyper::upgrade::OnUpgrade,
+    runtime: Arc<WebProcessRuntime>,
+    session: Arc<WebSession>,
+    connection: WebSocketConnection,
+    mut lane_reservation: Option<WebSocketLaneReservation>,
+    trace: Option<TraceWebSocketContext>,
+) {
+    let Ok(upgraded) = on_upgrade.await else {
+        return;
+    };
+    let Ok(parts) = upgraded.downcast::<TokioIo<ConnectionIo>>() else {
+        return;
+    };
+    let mut io = parts.io.into_inner();
+    io.enable_websocket(parts.read_buf);
+    let limits = runtime.active_generation().config().web.limits.clone();
+    let config = WebSocketConfig::default()
+        .read_buffer_size(READ_BUFFER_BYTES)
+        .write_buffer_size(WRITE_BUFFER_BYTES)
+        .max_write_buffer_size(
+            WRITE_BUFFER_BYTES
+                .saturating_add(limits.carrier_batch_bytes)
+                .saturating_add(1024),
+        )
+        .max_message_size(Some(limits.carrier_batch_bytes))
+        .max_frame_size(Some(limits.carrier_batch_bytes));
+    let mut socket = WebSocketStream::from_raw_socket(io, Role::Server, Some(config)).await;
+    connection.mark_opened();
+    let cancellation = connection.cancellation();
+    if let Some(reservation) = lane_reservation.as_mut() {
+        let _ = run_lane(
+            &mut socket,
+            &runtime,
+            &session,
+            &connection,
+            reservation,
+            cancellation.clone(),
+            trace.as_ref(),
+        )
+        .await;
+    } else {
+        let _ = run_multiplex(
+            &mut socket,
+            &runtime,
+            &session,
+            &connection,
+            cancellation.clone(),
+            trace.as_ref(),
+        )
+        .await;
+    }
+    let eviction = Duration::from_secs(
+        runtime
+            .active_generation()
+            .config()
+            .web
+            .timeouts
+            .websocket_eviction_secs,
+    );
+    let _ = tokio::time::timeout(eviction, socket.close(None)).await;
+    if let Some(reservation) = lane_reservation {
+        session.close_websocket_lane(reservation.lane_id());
+        drop(reservation);
+    } else {
+        session.close();
+    }
+}
+
+type CarrierSocket = WebSocketStream<ConnectionIo>;
+
+async fn run_multiplex(
+    socket: &mut CarrierSocket,
+    runtime: &Arc<WebProcessRuntime>,
+    session: &Arc<WebSession>,
+    connection: &WebSocketConnection,
+    cancellation: CancellationToken,
+    trace: Option<&TraceWebSocketContext>,
+) -> Result<(), ()> {
+    let mut sequence = 1u64;
+    let mut cursor = 0u64;
+    // The lease survives cancelled select branches and control frames interleaved
+    // inside one fragmented data message.
+    let mut read_budget = None;
+    let liveness_interval = connection.liveness_interval();
+    let mut next_ping = Instant::now() + liveness_interval;
+    loop {
+        let down = session.poll_down(cursor);
+        tokio::pin!(down);
+        let event = tokio::select! {
+            _ = cancellation.cancelled() => return Err(()),
+            _ = tokio::time::sleep_until(next_ping.into()) => DriverEvent::Liveness,
+            incoming = read_message(
+                socket,
+                runtime,
+                session.profile_key(),
+                &cancellation,
+                &mut read_budget,
+            ) => {
+                DriverEvent::Incoming(incoming?)
+            }
+            down = &mut down => DriverEvent::Down(down.map_err(|_| ())?),
+        };
+        match event {
+            DriverEvent::Incoming((message, _budget)) => match message {
+                Message::Binary(body) => {
+                    let started = Instant::now();
+                    let result =
+                        process_multiplex(runtime, session, sequence, &body, &cancellation).await;
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "binary",
+                        &body,
+                        started,
+                    );
+                    result?;
+                    sequence = sequence.checked_add(1).ok_or(())?;
+                    connection.mark_peer_activity();
+                    next_ping = Instant::now() + liveness_interval;
+                }
+                Message::Pong(payload) => {
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "pong",
+                        &payload,
+                        Instant::now(),
+                    );
+                    connection.mark_peer_activity();
+                    next_ping = Instant::now() + liveness_interval;
+                }
+                Message::Ping(payload) => {
+                    let started = Instant::now();
+                    flush(socket, runtime).await?;
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "ping",
+                        &payload,
+                        started,
+                    );
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Response,
+                        "pong",
+                        &payload,
+                        started,
+                    );
+                    connection.mark_peer_activity();
+                    next_ping = Instant::now() + liveness_interval;
+                }
+                Message::Close(_) => {
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "close",
+                        &[],
+                        Instant::now(),
+                    );
+                    return Ok(());
+                }
+                Message::Text(text) => {
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "text",
+                        text.as_bytes(),
+                        Instant::now(),
+                    );
+                    return Err(());
+                }
+                Message::Frame(_) => return Err(()),
+            },
+            DriverEvent::Down(result) => {
+                if result.body.is_empty() {
+                    let started = Instant::now();
+                    send(socket, runtime, Message::Ping(Bytes::new())).await?;
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Response,
+                        "ping",
+                        &[],
+                        started,
+                    );
+                    next_ping = Instant::now() + liveness_interval;
+                } else {
+                    let _budget = reserve_data(
+                        runtime,
+                        session.profile_key(),
+                        result.body.len(),
+                        &cancellation,
+                    )
+                    .await?;
+                    let body = result.body;
+                    let started = Instant::now();
+                    if trace.is_some() {
+                        send(socket, runtime, Message::Binary(body.clone())).await?;
+                        record_message(
+                            runtime,
+                            trace,
+                            TraceDirection::Response,
+                            "binary",
+                            &body,
+                            started,
+                        );
+                    } else {
+                        send(socket, runtime, Message::Binary(body)).await?;
+                    }
+                    connection.mark_progress();
+                }
+                cursor = result.next_cursor;
+            }
+            DriverEvent::Liveness => {
+                let started = Instant::now();
+                send(socket, runtime, Message::Ping(Bytes::new())).await?;
+                record_message(
+                    runtime,
+                    trace,
+                    TraceDirection::Response,
+                    "ping",
+                    &[],
+                    started,
+                );
+                next_ping = Instant::now() + liveness_interval;
+            }
+        }
+    }
+}
+
+async fn run_lane(
+    socket: &mut CarrierSocket,
+    runtime: &Arc<WebProcessRuntime>,
+    session: &Arc<WebSession>,
+    connection: &WebSocketConnection,
+    reservation: &mut WebSocketLaneReservation,
+    cancellation: CancellationToken,
+    trace: Option<&TraceWebSocketContext>,
+) -> Result<(), ()> {
+    let mut sequence = 1u64;
+    let mut cursor = 0u64;
+    // Lane reads use the same cancellation-safe fragmented-message ownership.
+    let mut read_budget = None;
+    let liveness_interval = connection.liveness_interval();
+    let mut next_ping = Instant::now() + liveness_interval;
+    loop {
+        let down = session.poll_down_lane(reservation.lane_id(), cursor);
+        tokio::pin!(down);
+        let event = tokio::select! {
+            _ = cancellation.cancelled() => return Err(()),
+            _ = tokio::time::sleep_until(next_ping.into()) => DriverEvent::Liveness,
+            incoming = read_message(
+                socket,
+                runtime,
+                session.profile_key(),
+                &cancellation,
+                &mut read_budget,
+            ) => {
+                DriverEvent::Incoming(incoming?)
+            }
+            down = &mut down => DriverEvent::Down(down.map_err(|_| ())?),
+        };
+        match event {
+            DriverEvent::Incoming((message, _budget)) => match message {
+                Message::Binary(body) => {
+                    let started = Instant::now();
+                    let result = process_lane(
+                        runtime,
+                        session,
+                        reservation,
+                        sequence,
+                        &body,
+                        &cancellation,
+                    )
+                    .await;
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "binary",
+                        &body,
+                        started,
+                    );
+                    result?;
+                    sequence = sequence.checked_add(1).ok_or(())?;
+                    connection.mark_peer_activity();
+                    next_ping = Instant::now() + liveness_interval;
+                }
+                Message::Pong(payload) => {
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "pong",
+                        &payload,
+                        Instant::now(),
+                    );
+                    connection.mark_peer_activity();
+                    next_ping = Instant::now() + liveness_interval;
+                }
+                Message::Ping(payload) => {
+                    let started = Instant::now();
+                    flush(socket, runtime).await?;
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "ping",
+                        &payload,
+                        started,
+                    );
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Response,
+                        "pong",
+                        &payload,
+                        started,
+                    );
+                    connection.mark_peer_activity();
+                    next_ping = Instant::now() + liveness_interval;
+                }
+                Message::Close(_) => {
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "close",
+                        &[],
+                        Instant::now(),
+                    );
+                    return Ok(());
+                }
+                Message::Text(text) => {
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Request,
+                        "text",
+                        text.as_bytes(),
+                        Instant::now(),
+                    );
+                    return Err(());
+                }
+                Message::Frame(_) => return Err(()),
+            },
+            DriverEvent::Down(result) => {
+                if result.lane_closed {
+                    return Ok(());
+                }
+                if result.body.is_empty() {
+                    let started = Instant::now();
+                    send(socket, runtime, Message::Ping(Bytes::new())).await?;
+                    record_message(
+                        runtime,
+                        trace,
+                        TraceDirection::Response,
+                        "ping",
+                        &[],
+                        started,
+                    );
+                    next_ping = Instant::now() + liveness_interval;
+                } else {
+                    let _budget = reserve_data(
+                        runtime,
+                        session.profile_key(),
+                        result.body.len(),
+                        &cancellation,
+                    )
+                    .await?;
+                    let body = result.body;
+                    let started = Instant::now();
+                    if trace.is_some() {
+                        send(socket, runtime, Message::Binary(body.clone())).await?;
+                        record_message(
+                            runtime,
+                            trace,
+                            TraceDirection::Response,
+                            "binary",
+                            &body,
+                            started,
+                        );
+                    } else {
+                        send(socket, runtime, Message::Binary(body)).await?;
+                    }
+                    connection.mark_progress();
+                }
+                cursor = result.next_cursor;
+            }
+            DriverEvent::Liveness => {
+                let started = Instant::now();
+                send(socket, runtime, Message::Ping(Bytes::new())).await?;
+                record_message(
+                    runtime,
+                    trace,
+                    TraceDirection::Response,
+                    "ping",
+                    &[],
+                    started,
+                );
+                next_ping = Instant::now() + liveness_interval;
+            }
+        }
+    }
+}
+
+enum DriverEvent {
+    Incoming((Message, Option<WebSocketBudgetLease>)),
+    Down(crate::web::session::PollResult),
+    Liveness,
+}
+
+async fn read_message(
+    socket: &mut CarrierSocket,
+    runtime: &Arc<WebProcessRuntime>,
+    owner: crate::web::manager::ProfileKey,
+    cancellation: &CancellationToken,
+    retained_budget: &mut Option<WebSocketBudgetLease>,
+) -> Result<(Message, Option<WebSocketBudgetLease>), ()> {
+    tokio::select! {
+        _ = cancellation.cancelled() => return Err(()),
+        ready = socket.get_ref().readable() => ready.map_err(|_| ())?,
+    }
+    if retained_budget.is_none() {
+        let maximum = runtime
+            .active_generation()
+            .config()
+            .web
+            .limits
+            .carrier_batch_bytes;
+        *retained_budget = Some(reserve_data(runtime, owner, maximum, cancellation).await?);
+    }
+    let message = tokio::select! {
+        _ = cancellation.cancelled() => return Err(()),
+        message = socket.next() => message.ok_or(())?.map_err(|_| ())?,
+    };
+    if socket.get_ref().websocket_fragmented_message() {
+        return Ok((message, None));
+    }
+    let mut budget = retained_budget.take().ok_or(())?;
+    budget.shrink_to(message.len());
+    Ok((message, Some(budget)))
+}
+
+async fn reserve_data(
+    runtime: &Arc<WebProcessRuntime>,
+    owner: crate::web::manager::ProfileKey,
+    bytes: usize,
+    cancellation: &CancellationToken,
+) -> Result<WebSocketBudgetLease, ()> {
+    let timeout = Duration::from_secs(
+        runtime
+            .active_generation()
+            .config()
+            .web
+            .timeouts
+            .websocket_backpressure_secs,
+    );
+    tokio::time::timeout(timeout, async {
+        loop {
+            let notify = runtime.budget_notify();
+            let notified = notify.notified();
+            if let Some(budget) = runtime.try_websocket_data_budget(owner, bytes.max(1)) {
+                return Ok(budget);
+            }
+            tokio::select! {
+                _ = cancellation.cancelled() => return Err(()),
+                _ = notified => {}
+            }
+        }
+    })
+    .await
+    .map_err(|_| ())?
+}
+
+async fn process_multiplex(
+    runtime: &Arc<WebProcessRuntime>,
+    session: &Arc<WebSession>,
+    sequence: u64,
+    body: &[u8],
+    cancellation: &CancellationToken,
+) -> Result<(), ()> {
+    retry_backpressure(runtime, cancellation, || {
+        session.process_up(sequence, body).map(|_| ())
+    })
+    .await
+}
+
+async fn process_lane(
+    runtime: &Arc<WebProcessRuntime>,
+    session: &Arc<WebSession>,
+    reservation: &mut WebSocketLaneReservation,
+    sequence: u64,
+    body: &[u8],
+    cancellation: &CancellationToken,
+) -> Result<(), ()> {
+    let timeout = Duration::from_secs(
+        runtime
+            .active_generation()
+            .config()
+            .web
+            .timeouts
+            .websocket_backpressure_secs,
+    );
+    tokio::time::timeout(timeout, async {
+        loop {
+            let notify = runtime.budget_notify();
+            let notified = notify.notified();
+            match session.process_websocket_lane(reservation, sequence, body) {
+                Ok(()) => return Ok(()),
+                Err(ManagerError::Backpressure) => {}
+                Err(_) => return Err(()),
+            }
+            tokio::select! {
+                _ = cancellation.cancelled() => return Err(()),
+                _ = notified => {}
+            }
+        }
+    })
+    .await
+    .map_err(|_| ())?
+}
+
+async fn retry_backpressure<F>(
+    runtime: &Arc<WebProcessRuntime>,
+    cancellation: &CancellationToken,
+    mut operation: F,
+) -> Result<(), ()>
+where
+    F: FnMut() -> Result<(), ManagerError>,
+{
+    let timeout = Duration::from_secs(
+        runtime
+            .active_generation()
+            .config()
+            .web
+            .timeouts
+            .websocket_backpressure_secs,
+    );
+    tokio::time::timeout(timeout, async {
+        loop {
+            let notify = runtime.budget_notify();
+            let notified = notify.notified();
+            match operation() {
+                Ok(()) => return Ok(()),
+                Err(ManagerError::Backpressure) => {}
+                Err(_) => return Err(()),
+            }
+            tokio::select! {
+                _ = cancellation.cancelled() => return Err(()),
+                _ = notified => {}
+            }
+        }
+    })
+    .await
+    .map_err(|_| ())?
+}
+
+async fn send(
+    socket: &mut CarrierSocket,
+    runtime: &WebProcessRuntime,
+    message: Message,
+) -> Result<(), ()> {
+    let timeout = Duration::from_secs(
+        runtime
+            .active_generation()
+            .config()
+            .web
+            .timeouts
+            .websocket_write_secs,
+    );
+    tokio::time::timeout(timeout, socket.send(message))
+        .await
+        .map_err(|_| ())?
+        .map_err(|_| ())
+}
+
+async fn flush(socket: &mut CarrierSocket, runtime: &WebProcessRuntime) -> Result<(), ()> {
+    let timeout = Duration::from_secs(
+        runtime
+            .active_generation()
+            .config()
+            .web
+            .timeouts
+            .websocket_write_secs,
+    );
+    tokio::time::timeout(timeout, socket.flush())
+        .await
+        .map_err(|_| ())?
+        .map_err(|_| ())
+}
+
+fn record_message(
+    runtime: &WebProcessRuntime,
+    trace: Option<&TraceWebSocketContext>,
+    direction: TraceDirection,
+    message_type: &'static str,
+    payload: &[u8],
+    started: Instant,
+) {
+    let Some(trace) = trace else {
+        return;
+    };
+    runtime.trace().record_websocket_message(
+        trace,
+        direction,
+        message_type,
+        payload,
+        started.elapsed().as_micros().min(u128::from(u64::MAX)) as u64,
+    );
+}
diff --git a/src/web/http/websocket/tests.rs b/src/web/http/websocket/tests.rs
new file mode 100644
index 0000000..0f42572
--- /dev/null
+++ b/src/web/http/websocket/tests.rs
@@ -0,0 +1,311 @@
+use super::*;
+
+use std::sync::Arc;
+use std::time::Duration;
+
+use arc_swap::ArcSwap;
+use futures_util::{SinkExt, StreamExt};
+use sha2::{Digest, Sha256};
+use tokio::io::{AsyncReadExt, AsyncWriteExt};
+use tokio::net::{TcpListener, TcpStream};
+use tokio_tungstenite::WebSocketStream;
+use tokio_tungstenite::tungstenite::protocol::{Message, Role};
+use tokio_util::sync::CancellationToken;
+
+use crate::maestro::generation::{RuntimeGeneration, test_runtime_generation};
+use crate::web::frame::{self, FrameType};
+use crate::web::http::tests::runtime_config;
+use crate::web::manager::WebProcessRuntime;
+
+fn request(protocol: &str) -> Request<()> {
+    Request::builder()
+        .method(Method::GET)
+        .uri("/api/v1/ws")
+        .header(header::CONNECTION, "keep-alive, Upgrade")
+        .header(header::UPGRADE, "websocket")
+        .header("sec-websocket-version", "13")
+        .header("sec-websocket-key", "dGhlIHNhbXBsZSBub25jZQ==")
+        .header("sec-websocket-protocol", protocol)
+        .body(())
+        .unwrap()
+}
+
+#[test]
+fn canonical_multiplex_and_lane_protocols_are_accepted() {
+    let token = base64::engine::general_purpose::URL_SAFE_NO_PAD.encode([7u8; 32]);
+    let multiplex = parse_upgrade(&request(&format!("tproxy-v1.{token}"))).unwrap();
+    assert!(matches!(multiplex.carrier, ParsedCarrier::Multiplex));
+    assert_eq!(multiplex.accept, "s3pPLMBiTxaQ9kYGzzhZRbK+xOo=");
+
+    let lane = parse_upgrade(&request(&format!("tproxy-lane-v1.{token}.16777215"))).unwrap();
+    assert!(matches!(lane.carrier, ParsedCarrier::Lane(16_777_215)));
+}
+
+#[test]
+fn aliases_authorization_and_request_bodies_are_rejected_before_upgrade() {
+    let token = base64::engine::general_purpose::URL_SAFE_NO_PAD.encode([9u8; 32]);
+    assert!(parse_upgrade(&request(&format!("tproxy-lane-v1.{token}.01"))).is_none());
+    assert!(parse_upgrade(&request(&format!("tproxy-lane-v1.{token}.0"))).is_none());
+
+    let with_authorization = Request::builder()
+        .method(Method::GET)
+        .uri("/api/v1/ws")
+        .header(header::CONNECTION, "Upgrade")
+        .header(header::UPGRADE, "websocket")
+        .header(header::AUTHORIZATION, "Bearer hidden")
+        .header("sec-websocket-version", "13")
+        .header("sec-websocket-key", "dGhlIHNhbXBsZSBub25jZQ==")
+        .header("sec-websocket-protocol", format!("tproxy-v1.{token}"))
+        .body(())
+        .unwrap();
+    assert!(parse_upgrade(&with_authorization).is_none());
+
+    let with_body = Request::builder()
+        .method(Method::GET)
+        .uri("/api/v1/ws")
+        .header(header::CONNECTION, "Upgrade")
+        .header(header::UPGRADE, "websocket")
+        .header(header::CONTENT_LENGTH, "1")
+        .header("sec-websocket-version", "13")
+        .header("sec-websocket-key", "dGhlIHNhbXBsZSBub25jZQ==")
+        .header("sec-websocket-protocol", format!("tproxy-v1.{token}"))
+        .body(())
+        .unwrap();
+    assert!(parse_upgrade(&with_body).is_none());
+}
+
+struct LiveRuntime {
+    runtime: Arc<WebProcessRuntime>,
+    generation: Arc<RuntimeGeneration>,
+}
+
+impl LiveRuntime {
+    async fn shutdown(self) {
+        self.runtime.shutdown().await;
+        self.generation.stop_sessions().await;
+        self.generation.stop_background_tasks().await;
+    }
+}
+
+fn live_runtime(carrier: WebCarrier) -> LiveRuntime {
+    live_runtime_with_long_poll(carrier, 1)
+}
+
+fn live_runtime_with_long_poll(carrier: WebCarrier, long_poll_secs: u64) -> LiveRuntime {
+    let mut config = runtime_config([31; 32], carrier);
+    config.web.timeouts.long_poll_secs = long_poll_secs;
+    config.web.timeouts.websocket_write_secs = 2;
+    config.web.timeouts.websocket_backpressure_secs = 2;
+    config.web.timeouts.websocket_eviction_secs = 1;
+    let generation = test_runtime_generation(1, config);
+    let runtime = WebProcessRuntime::start(Arc::new(ArcSwap::from(Arc::clone(&generation))));
+    LiveRuntime {
+        runtime,
+        generation,
+    }
+}
+
+fn create_session(runtime: &Arc<WebProcessRuntime>) -> (String, TokenHash) {
+    let profile = runtime
+        .active_generation()
+        .config()
+        .web
+        .runtime
+        .as_ref()
+        .unwrap()
+        .profiles[0]
+        .clone();
+    let client_ip = "192.0.2.10".parse().unwrap();
+    let bootstrap = runtime.issue_bootstrap(profile, client_ip).unwrap().token;
+    let raw = base64::engine::general_purpose::URL_SAFE_NO_PAD
+        .decode(&bootstrap)
+        .unwrap();
+    let bootstrap_hash = Sha256::digest(raw).into();
+    let hello = frame::encode(FrameType::Hello, 0, &[1]);
+    let session = runtime
+        .create_session(bootstrap_hash, "proxy.example.com", client_ip, &hello)
+        .unwrap()
+        .token;
+    let raw = base64::engine::general_purpose::URL_SAFE_NO_PAD
+        .decode(&session)
+        .unwrap();
+    let session_hash = Sha256::digest(raw).into();
+    (session, session_hash)
+}
+
+async fn upgrade(
+    listener: &TcpListener,
+    runtime: &Arc<WebProcessRuntime>,
+    protocol: &str,
+) -> WebSocketStream<TcpStream> {
+    let addr = listener.local_addr().unwrap();
+    let (accepted, client) = tokio::join!(listener.accept(), TcpStream::connect(addr));
+    let (server, peer) = accepted.unwrap();
+    let mut client = client.unwrap();
+    let permit = runtime.try_http_connection().unwrap();
+    tokio::spawn(super::super::serve_connection(
+        server,
+        peer,
+        WebClientIpSource::XForwardedFor,
+        Arc::from(["127.0.0.1/32".parse().unwrap()]),
+        Arc::clone(runtime),
+        CancellationToken::new(),
+        permit,
+    ));
+    let request = format!(
+        "GET /api/v1/ws HTTP/1.1\r\nHost: proxy.example.com\r\nX-Forwarded-For: 192.0.2.10\r\nConnection: Upgrade\r\nUpgrade: websocket\r\nSec-WebSocket-Version: 13\r\nSec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==\r\nSec-WebSocket-Protocol: {protocol}\r\nCookie: browser-state=allowed\r\n\r\n"
+    );
+    client.write_all(request.as_bytes()).await.unwrap();
+    let mut response = Vec::new();
+    while !response.ends_with(b"\r\n\r\n") {
+        let byte = client.read_u8().await.unwrap();
+        response.push(byte);
+        assert!(response.len() <= 16 * 1024);
+    }
+    assert!(response.starts_with(b"HTTP/1.1 101"));
+    assert!(
+        std::str::from_utf8(&response)
+            .unwrap()
+            .contains(&format!("sec-websocket-protocol: {protocol}"))
+    );
+    WebSocketStream::from_raw_socket(client, Role::Client, None).await
+}
+
+fn masked_message(opcode: u8, payload: &[u8], mask: [u8; 4]) -> Vec<u8> {
+    masked_frame(true, opcode, payload, mask)
+}
+
+fn masked_frame(finished: bool, opcode: u8, payload: &[u8], mask: [u8; 4]) -> Vec<u8> {
+    assert!(payload.len() < 126);
+    let mut encoded = Vec::with_capacity(payload.len() + 6);
+    encoded.push(u8::from(finished) << 7 | opcode);
+    encoded.push(0x80 | payload.len() as u8);
+    encoded.extend_from_slice(&mask);
+    encoded.extend(
+        payload
+            .iter()
+            .enumerate()
+            .map(|(index, value)| value ^ mask[index % mask.len()]),
+    );
+    encoded
+}
+
+#[tokio::test]
+async fn multiplex_upgrade_relays_binary_and_transport_control_messages() {
+    let live = live_runtime(WebCarrier::Websocket);
+    let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+    let (session, _) = create_session(&live.runtime);
+    let protocol = format!("tproxy-v1.{session}");
+    let mut socket = upgrade(&listener, &live.runtime, &protocol).await;
+
+    socket
+        .send(Message::Binary(frame::encode(FrameType::Pong, 0, &[])))
+        .await
+        .unwrap();
+    socket
+        .send(Message::Ping(Bytes::from_static(b"live")))
+        .await
+        .unwrap();
+    let response = tokio::time::timeout(Duration::from_secs(2), socket.next())
+        .await
+        .unwrap()
+        .unwrap()
+        .unwrap();
+    assert_eq!(response, Message::Pong(Bytes::from_static(b"live")));
+
+    let _ = socket.close(None).await;
+    live.shutdown().await;
+}
+
+#[tokio::test]
+async fn coalesced_websocket_messages_do_not_wait_for_new_tcp_readiness() {
+    let live = live_runtime_with_long_poll(WebCarrier::Websocket, 10);
+    let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+    let (session, _) = create_session(&live.runtime);
+    let protocol = format!("tproxy-v1.{session}");
+    let mut socket = upgrade(&listener, &live.runtime, &protocol).await;
+    let mut wire = masked_message(0x02, &frame::encode(FrameType::Pong, 0, &[]), [1, 2, 3, 4]);
+    wire.extend_from_slice(&masked_message(0x09, b"coalesced", [5, 6, 7, 8]));
+    socket.get_mut().write_all(&wire).await.unwrap();
+
+    let response = tokio::time::timeout(Duration::from_secs(2), socket.next())
+        .await
+        .unwrap()
+        .unwrap()
+        .unwrap();
+    assert_eq!(response, Message::Pong(Bytes::from_static(b"coalesced")));
+
+    let _ = socket.close(None).await;
+    live.shutdown().await;
+}
+
+#[tokio::test]
+async fn fragmented_message_budget_survives_interleaved_control_frames() {
+    let live = live_runtime_with_long_poll(WebCarrier::Websocket, 10);
+    let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+    let (session, _) = create_session(&live.runtime);
+    let protocol = format!("tproxy-v1.{session}");
+    let mut socket = upgrade(&listener, &live.runtime, &protocol).await;
+    let body = frame::encode(FrameType::Pong, 0, &[]);
+    let mut wire = masked_frame(false, 0x02, &body[..4], [1, 2, 3, 4]);
+    wire.extend_from_slice(&masked_message(0x09, b"mid", [5, 6, 7, 8]));
+    wire.extend_from_slice(&masked_frame(true, 0x00, &body[4..], [9, 10, 11, 12]));
+    wire.extend_from_slice(&masked_message(0x09, b"after", [13, 14, 15, 16]));
+    socket.get_mut().write_all(&wire).await.unwrap();
+
+    for expected in [b"mid".as_slice(), b"after".as_slice()] {
+        let response = tokio::time::timeout(Duration::from_secs(2), socket.next())
+            .await
+            .unwrap()
+            .unwrap()
+            .unwrap();
+        assert_eq!(response, Message::Pong(Bytes::copy_from_slice(expected)));
+    }
+
+    let _ = socket.close(None).await;
+    live.shutdown().await;
+}
+
+#[tokio::test]
+async fn malformed_websocket_lane_closes_only_that_lane() {
+    let live = live_runtime(WebCarrier::WebsocketLanes);
+    let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+    let (session, session_hash) = create_session(&live.runtime);
+    let first_protocol = format!("tproxy-lane-v1.{session}.7");
+    let mut first = upgrade(&listener, &live.runtime, &first_protocol).await;
+    first
+        .send(Message::Binary(frame::encode(FrameType::Data, 7, &[1])))
+        .await
+        .unwrap();
+    let closed = tokio::time::timeout(Duration::from_secs(2), first.next())
+        .await
+        .unwrap()
+        .unwrap()
+        .unwrap();
+    assert!(matches!(closed, Message::Close(_)));
+    assert!(
+        live.runtime
+            .get_session(session_hash, "proxy.example.com")
+            .is_ok()
+    );
+
+    let second_protocol = format!("tproxy-lane-v1.{session}.8");
+    let mut second = upgrade(&listener, &live.runtime, &second_protocol).await;
+    second
+        .send(Message::Binary(frame::encode(FrameType::Open, 8, &[])))
+        .await
+        .unwrap();
+    second
+        .send(Message::Ping(Bytes::from_static(b"lane")))
+        .await
+        .unwrap();
+    let pong = tokio::time::timeout(Duration::from_secs(2), second.next())
+        .await
+        .unwrap()
+        .unwrap()
+        .unwrap();
+    assert_eq!(pong, Message::Pong(Bytes::from_static(b"lane")));
+
+    let _ = second.close(None).await;
+    live.shutdown().await;
+}
diff --git a/src/web/manager.rs b/src/web/manager.rs
index 47ecc53..86f222c 100644
--- a/src/web/manager.rs
+++ b/src/web/manager.rs
@@ -1,6 +1,7 @@
 use std::future::Future;
+use std::net::IpAddr;
 use std::sync::Arc;
-use std::sync::atomic::{AtomicBool, AtomicU64, Ordering};
+use std::sync::atomic::{AtomicU64, Ordering};
 use std::time::Duration;
 
 use arc_swap::ArcSwap;
@@ -21,7 +22,14 @@ mod credentials;
 mod admission;
 // Shutdown and expiry work remain outside request-path coordination.
 mod lifecycle;
-use state::{ManagerState, control_item_reserve};
+// Queue and WebSocket allocations share one process-owned data-plane budget.
+mod budget;
+// WebSocket admission, replacement, and liveness are process-scoped.
+mod websocket;
+pub(crate) use budget::WebSocketBudgetLease;
+use budget::{WebDataBudget, WebSocketBudgetClass};
+use state::ManagerState;
+pub(crate) use websocket::{WebSocketConnection, WebSocketKind};
 
 const TOKEN_BYTES: usize = 32;
 const CLEANUP_INTERVAL: Duration = Duration::from_secs(1);
@@ -76,8 +84,12 @@ pub(crate) struct WebProcessRuntime {
     body_readers: Arc<Semaphore>,
     body_bytes: Arc<Semaphore>,
     stream_handshakes: Arc<Semaphore>,
-    budget_notify: Arc<Notify>,
-    budget_saturated: AtomicBool,
+    websocket_connections: Arc<Semaphore>,
+    websockets: Mutex<websocket::WebSocketRegistry>,
+    websocket_next_id: AtomicU64,
+    websocket_clock: std::time::Instant,
+    websocket_notify: Arc<Notify>,
+    data_budget: Arc<WebDataBudget>,
     shutdown: CancellationToken,
     tasks: TaskTracker,
     sessions_created: AtomicU64,
@@ -104,6 +116,9 @@ impl WebProcessRuntime {
         trace: Arc<WebTraceStore>,
     ) -> Arc<Self> {
         let limits = active_runtime.load().config().web.limits.clone();
+        let websocket_connections = limits
+            .max_http_connections
+            .saturating_sub(limits.websocket_http_connection_reserve);
         let runtime = Arc::new(Self {
             active_runtime,
             trace,
@@ -113,10 +128,14 @@ impl WebProcessRuntime {
             body_readers: Arc::new(Semaphore::new(limits.max_body_readers)),
             body_bytes: Arc::new(Semaphore::new(limits.max_body_bytes_global)),
             stream_handshakes: Arc::new(Semaphore::new(limits.max_stream_handshakes)),
+            websocket_connections: Arc::new(Semaphore::new(websocket_connections)),
+            websockets: Mutex::new(websocket::WebSocketRegistry::default()),
+            websocket_next_id: AtomicU64::new(1),
+            websocket_clock: std::time::Instant::now(),
+            websocket_notify: Arc::new(Notify::new()),
+            data_budget: WebDataBudget::new(limits.clone()),
             limits,
             state: Mutex::new(ManagerState::default()),
-            budget_notify: Arc::new(Notify::new()),
-            budget_saturated: AtomicBool::new(false),
             shutdown: CancellationToken::new(),
             tasks: TaskTracker::new(),
             sessions_created: AtomicU64::new(0),
@@ -235,89 +254,80 @@ impl WebProcessRuntime {
     /// Reserves bounded process-wide queue capacity for data or control traffic.
     pub(crate) fn try_reserve_pending(
         &self,
+        owner: ProfileKey,
         bytes: usize,
         items: usize,
         control: bool,
         downlink: bool,
     ) -> bool {
-        let mut state = self.state.lock();
-        let data_byte_limit = self
-            .limits
-            .pending_bytes_global
-            .saturating_sub(self.limits.control_bytes_global);
-        let control_item_reserve = control_item_reserve(&self.limits);
-        let data_item_limit = self
-            .limits
-            .pending_items_global
-            .saturating_sub(control_item_reserve);
-        if state.closed {
-            return false;
-        }
-        let fits = if control {
-            bytes <= self.limits.control_bytes_global
-                && items <= control_item_reserve
-                && state.pending_bytes <= self.limits.pending_bytes_global.saturating_sub(bytes)
-                && state.pending_items <= self.limits.pending_items_global.saturating_sub(items)
-                && state.pending_control_bytes
-                    <= self.limits.control_bytes_global.saturating_sub(bytes)
-                && state.pending_control_items <= control_item_reserve.saturating_sub(items)
-        } else {
-            let data_bytes = state
-                .pending_bytes
-                .saturating_sub(state.pending_control_bytes);
-            let data_items = state
-                .pending_items
-                .saturating_sub(state.pending_control_items);
-            let (byte_limit, item_limit) = if downlink {
-                let uplink_bytes = self.limits.max_body_bytes.saturating_add(
-                    self.limits
-                        .max_frames_per_body
-                        .saturating_mul(crate::web::session::QUEUE_ITEM_COST),
-                );
-                (
-                    data_byte_limit.saturating_sub(uplink_bytes),
-                    data_item_limit.saturating_sub(self.limits.max_frames_per_body),
-                )
-            } else {
-                (data_byte_limit, data_item_limit)
-            };
-            bytes <= byte_limit
-                && items <= item_limit
-                && data_bytes <= byte_limit - bytes
-                && data_items <= item_limit - items
-        };
-        if !fits {
-            self.budget_saturated.store(true, Ordering::Release);
+        if !self
+            .data_budget
+            .try_reserve_queue(owner, bytes, items, control, downlink)
+        {
             self.record_limit_hit();
             return false;
         }
-        state.pending_bytes += bytes;
-        state.pending_items += items;
-        if control {
-            state.pending_control_bytes += bytes;
-            state.pending_control_items += items;
-        }
         true
     }
 
     /// Releases process-wide queue capacity and wakes blocked relay writers.
-    pub(crate) fn release_pending(&self, bytes: usize, items: usize, control: bool) {
-        let mut state = self.state.lock();
-        state.pending_bytes = state.pending_bytes.saturating_sub(bytes);
-        state.pending_items = state.pending_items.saturating_sub(items);
-        if control {
-            state.pending_control_bytes = state.pending_control_bytes.saturating_sub(bytes);
-            state.pending_control_items = state.pending_control_items.saturating_sub(items);
-        }
-        drop(state);
-        if self.budget_saturated.swap(false, Ordering::AcqRel) {
-            self.budget_notify.notify_waiters();
-        }
+    pub(crate) fn release_pending(
+        &self,
+        owner: ProfileKey,
+        bytes: usize,
+        items: usize,
+        control: bool,
+    ) {
+        self.data_budget.release_queue(owner, bytes, items, control);
     }
 
     /// Returns the shared notification source for global queue capacity changes.
     pub(crate) fn budget_notify(&self) -> Arc<Notify> {
-        Arc::clone(&self.budget_notify)
+        self.data_budget.notify()
+    }
+
+    /// Reserves fixed WebSocket driver memory below the admission watermark.
+    pub(crate) fn try_websocket_base_budget(
+        &self,
+        owner: ProfileKey,
+        bytes: usize,
+    ) -> Option<WebSocketBudgetLease> {
+        self.data_budget
+            .try_reserve_websocket(owner, bytes, WebSocketBudgetClass::Base)
+    }
+
+    /// Reserves one transient WebSocket message below the eviction watermark.
+    pub(crate) fn try_websocket_data_budget(
+        &self,
+        owner: ProfileKey,
+        bytes: usize,
+    ) -> Option<WebSocketBudgetLease> {
+        self.data_budget
+            .try_reserve_websocket(owner, bytes, WebSocketBudgetClass::Data)
+    }
+
+    /// Admits one WebSocket with owner-first bounded replacement.
+    pub(crate) async fn admit_websocket(
+        self: &Arc<Self>,
+        owner: ProfileKey,
+        session_id: u64,
+        client_ip: IpAddr,
+        kind: WebSocketKind,
+        base_bytes: usize,
+        liveness_interval: Duration,
+        eviction_timeout: Duration,
+    ) -> Result<WebSocketConnection, ManagerError> {
+        websocket::admit(
+            self,
+            owner,
+            session_id,
+            client_ip,
+            kind,
+            base_bytes,
+            liveness_interval,
+            eviction_timeout,
+        )
+        .await
     }
 
     /// Accounts one successfully committed carrier uplink body.
diff --git a/src/web/manager/admission.rs b/src/web/manager/admission.rs
index b1bc54e..be94f7e 100644
--- a/src/web/manager/admission.rs
+++ b/src/web/manager/admission.rs
@@ -84,7 +84,7 @@ mod tests {
     async fn global_downlink_budget_preserves_one_maximum_uplink_batch() {
         let generation = test_runtime_generation(1, ProxyConfig::default());
         let runtime = WebProcessRuntime::start(Arc::new(ArcSwap::from(generation)));
-        let control_items = super::super::state::control_item_reserve(&runtime.limits);
+        let control_items = super::super::budget::control_item_reserve(&runtime.limits);
         let data_bytes = runtime
             .limits
             .pending_bytes_global
@@ -97,20 +97,30 @@ mod tests {
             .limits
             .max_body_bytes
             .saturating_add(runtime.limits.max_frames_per_body * QUEUE_ITEM_COST);
-        let downlink_bytes = data_bytes - uplink_bytes;
+        let websocket_bytes = runtime.limits.carrier_batch_bytes;
+        let downlink_bytes = data_bytes - uplink_bytes - websocket_bytes;
         let downlink_items = data_items - runtime.limits.max_frames_per_body;
 
-        assert!(runtime.try_reserve_pending(downlink_bytes, downlink_items, false, true,));
+        assert!(runtime.try_reserve_pending([0; 32], downlink_bytes, downlink_items, false, true,));
         assert!(runtime.try_reserve_pending(
+            [0; 32],
             uplink_bytes,
             runtime.limits.max_frames_per_body,
             false,
             false,
         ));
-        assert!(!runtime.try_reserve_pending(1, 1, false, true));
+        let websocket = runtime.try_websocket_data_budget([0; 32], websocket_bytes);
+        assert!(websocket.is_some());
+        assert!(!runtime.try_reserve_pending([0; 32], 1, 1, false, true));
 
-        runtime.release_pending(downlink_bytes, downlink_items, false);
-        runtime.release_pending(uplink_bytes, runtime.limits.max_frames_per_body, false);
+        drop(websocket);
+        runtime.release_pending([0; 32], downlink_bytes, downlink_items, false);
+        runtime.release_pending(
+            [0; 32],
+            uplink_bytes,
+            runtime.limits.max_frames_per_body,
+            false,
+        );
         runtime.shutdown().await;
     }
 }
diff --git a/src/web/manager/budget.rs b/src/web/manager/budget.rs
new file mode 100644
index 0000000..b1fbeba
--- /dev/null
+++ b/src/web/manager/budget.rs
@@ -0,0 +1,366 @@
+use std::collections::HashMap;
+use std::sync::Arc;
+use std::sync::atomic::{AtomicBool, Ordering};
+
+use parking_lot::Mutex;
+use tokio::sync::Notify;
+
+use super::ProfileKey;
+use crate::config::WebLimitsConfig;
+use crate::web::session::QUEUE_ITEM_COST;
+
+/// WebSocket allocation class with a distinct pressure watermark.
+#[derive(Clone, Copy)]
+pub(super) enum WebSocketBudgetClass {
+    /// Long-lived codec and driver memory acquired before an upgrade commits.
+    Base,
+    /// One bounded inbound message or outbound write staging allocation.
+    Data,
+}
+
+#[derive(Default)]
+struct BudgetState {
+    queue_bytes: usize,
+    queue_items: usize,
+    queue_control_bytes: usize,
+    queue_control_items: usize,
+    websocket_bytes: usize,
+    owner_bytes: HashMap<ProfileKey, usize>,
+    high_water_bytes: usize,
+    closed: bool,
+}
+
+/// Process-owned byte and item governor shared by queues and WebSocket I/O.
+pub(super) struct WebDataBudget {
+    limits: WebLimitsConfig,
+    state: Mutex<BudgetState>,
+    notify: Arc<Notify>,
+    pressured: AtomicBool,
+}
+
+/// One exact WebSocket allocation released on every cancellation path.
+pub(crate) struct WebSocketBudgetLease {
+    budget: Arc<WebDataBudget>,
+    owner: ProfileKey,
+    bytes: usize,
+}
+
+/// Lock-free diagnostic snapshot of one short locked budget state.
+#[derive(Clone, Copy, Debug, Default)]
+pub(crate) struct WebDataBudgetSnapshot {
+    /// Total queue bytes currently retained.
+    pub(crate) queue_bytes: usize,
+    /// Total queue items currently retained.
+    pub(crate) queue_items: usize,
+    /// Total WebSocket bytes currently retained.
+    pub(crate) websocket_bytes: usize,
+    /// Largest combined byte usage observed since process start.
+    pub(crate) high_water_bytes: usize,
+}
+
+impl WebDataBudget {
+    pub(super) fn new(limits: WebLimitsConfig) -> Arc<Self> {
+        Arc::new(Self {
+            limits,
+            state: Mutex::new(BudgetState::default()),
+            notify: Arc::new(Notify::new()),
+            pressured: AtomicBool::new(false),
+        })
+    }
+
+    pub(super) fn try_reserve_queue(
+        &self,
+        owner: ProfileKey,
+        bytes: usize,
+        items: usize,
+        control: bool,
+        downlink: bool,
+    ) -> bool {
+        let mut state = self.state.lock();
+        if state.closed {
+            return false;
+        }
+        let control_item_reserve = control_item_reserve(&self.limits);
+        let data_byte_limit = self
+            .limits
+            .pending_bytes_global
+            .saturating_sub(self.limits.control_bytes_global);
+        let data_item_limit = self
+            .limits
+            .pending_items_global
+            .saturating_sub(control_item_reserve);
+        let (fits, websocket_byte_pressure) = if control {
+            let byte_pressure = state.websocket_bytes != 0
+                && state.queue_bytes.saturating_add(state.websocket_bytes)
+                    > self.limits.pending_bytes_global.saturating_sub(bytes);
+            let fits = bytes <= self.limits.control_bytes_global
+                && items <= control_item_reserve
+                && state.queue_bytes.saturating_add(state.websocket_bytes)
+                    <= self.limits.pending_bytes_global.saturating_sub(bytes)
+                && state.queue_items <= self.limits.pending_items_global.saturating_sub(items)
+                && state.queue_control_bytes
+                    <= self.limits.control_bytes_global.saturating_sub(bytes)
+                && state.queue_control_items <= control_item_reserve.saturating_sub(items);
+            (fits, byte_pressure)
+        } else {
+            let queue_data_bytes = state.queue_bytes.saturating_sub(state.queue_control_bytes);
+            let queue_data_items = state.queue_items.saturating_sub(state.queue_control_items);
+            let (byte_limit, item_limit) = if downlink {
+                let uplink_bytes = self.limits.max_body_bytes.saturating_add(
+                    self.limits
+                        .max_frames_per_body
+                        .saturating_mul(QUEUE_ITEM_COST),
+                );
+                (
+                    data_byte_limit
+                        .saturating_sub(uplink_bytes)
+                        .saturating_sub(self.limits.carrier_batch_bytes),
+                    data_item_limit.saturating_sub(self.limits.max_frames_per_body),
+                )
+            } else {
+                (data_byte_limit, data_item_limit)
+            };
+            let byte_pressure = state.websocket_bytes != 0
+                && queue_data_bytes.saturating_add(state.websocket_bytes)
+                    > byte_limit.saturating_sub(bytes);
+            let fits = bytes <= byte_limit
+                && items <= item_limit
+                && queue_data_bytes.saturating_add(state.websocket_bytes)
+                    <= byte_limit.saturating_sub(bytes)
+                && queue_data_items <= item_limit.saturating_sub(items);
+            (fits, byte_pressure)
+        };
+        if !fits {
+            if websocket_byte_pressure {
+                self.pressured.store(true, Ordering::Release);
+            }
+            return false;
+        }
+        state.queue_bytes += bytes;
+        state.queue_items += items;
+        if control {
+            state.queue_control_bytes += bytes;
+            state.queue_control_items += items;
+        }
+        add_owner(&mut state.owner_bytes, owner, bytes);
+        update_high_water(&mut state);
+        true
+    }
+
+    pub(super) fn release_queue(
+        &self,
+        owner: ProfileKey,
+        bytes: usize,
+        items: usize,
+        control: bool,
+    ) {
+        let mut state = self.state.lock();
+        state.queue_bytes = state.queue_bytes.saturating_sub(bytes);
+        state.queue_items = state.queue_items.saturating_sub(items);
+        if control {
+            state.queue_control_bytes = state.queue_control_bytes.saturating_sub(bytes);
+            state.queue_control_items = state.queue_control_items.saturating_sub(items);
+        }
+        remove_owner(&mut state.owner_bytes, owner, bytes);
+        drop(state);
+        self.pressured.store(false, Ordering::Release);
+        self.notify.notify_waiters();
+    }
+
+    pub(super) fn try_reserve_websocket(
+        self: &Arc<Self>,
+        owner: ProfileKey,
+        bytes: usize,
+        class: WebSocketBudgetClass,
+    ) -> Option<WebSocketBudgetLease> {
+        let mut state = self.state.lock();
+        if state.closed || bytes == 0 {
+            return None;
+        }
+        let websocket_limit = match class {
+            WebSocketBudgetClass::Base => watermark(
+                self.limits.websocket_bytes_global,
+                self.limits.websocket_admission_watermark_pct,
+            ),
+            WebSocketBudgetClass::Data => watermark(
+                self.limits.websocket_bytes_global,
+                self.limits.websocket_eviction_watermark_pct,
+            ),
+        };
+        let data_byte_limit = self
+            .limits
+            .pending_bytes_global
+            .saturating_sub(self.limits.control_bytes_global);
+        let queue_data_bytes = state.queue_bytes.saturating_sub(state.queue_control_bytes);
+        if state.websocket_bytes > websocket_limit.saturating_sub(bytes)
+            || queue_data_bytes.saturating_add(state.websocket_bytes)
+                > data_byte_limit.saturating_sub(bytes)
+        {
+            self.pressured.store(true, Ordering::Release);
+            return None;
+        }
+        state.websocket_bytes += bytes;
+        add_owner(&mut state.owner_bytes, owner, bytes);
+        update_high_water(&mut state);
+        Some(WebSocketBudgetLease {
+            budget: Arc::clone(self),
+            owner,
+            bytes,
+        })
+    }
+
+    pub(super) fn notify(&self) -> Arc<Notify> {
+        Arc::clone(&self.notify)
+    }
+
+    pub(super) fn take_pressure(&self) -> bool {
+        self.pressured.swap(false, Ordering::AcqRel)
+    }
+
+    pub(super) fn owner_usage(&self, owner: ProfileKey) -> usize {
+        self.state
+            .lock()
+            .owner_bytes
+            .get(&owner)
+            .copied()
+            .unwrap_or(0)
+    }
+
+    pub(super) fn fair_share(&self, additional_owner: Option<ProfileKey>) -> usize {
+        let state = self.state.lock();
+        let mut owners = state.owner_bytes.len();
+        if additional_owner.is_some_and(|owner| !state.owner_bytes.contains_key(&owner)) {
+            owners += 1;
+        }
+        let admission = watermark(
+            self.limits.websocket_bytes_global,
+            self.limits.websocket_admission_watermark_pct,
+        );
+        admission / owners.max(1)
+    }
+
+    pub(super) fn snapshot(&self) -> WebDataBudgetSnapshot {
+        let state = self.state.lock();
+        WebDataBudgetSnapshot {
+            queue_bytes: state.queue_bytes,
+            queue_items: state.queue_items,
+            websocket_bytes: state.websocket_bytes,
+            high_water_bytes: state.high_water_bytes,
+        }
+    }
+
+    pub(super) fn close(&self) {
+        self.state.lock().closed = true;
+        self.notify.notify_waiters();
+    }
+
+    fn release_websocket(&self, owner: ProfileKey, bytes: usize) {
+        let mut state = self.state.lock();
+        state.websocket_bytes = state.websocket_bytes.saturating_sub(bytes);
+        remove_owner(&mut state.owner_bytes, owner, bytes);
+        drop(state);
+        self.pressured.store(false, Ordering::Release);
+        self.notify.notify_waiters();
+    }
+}
+
+impl WebSocketBudgetLease {
+    /// Releases unused worst-case capacity after one message is assembled.
+    pub(crate) fn shrink_to(&mut self, bytes: usize) {
+        let bytes = bytes.min(self.bytes);
+        let released = self.bytes - bytes;
+        if released == 0 {
+            return;
+        }
+        self.bytes = bytes;
+        self.budget.release_websocket(self.owner, released);
+    }
+}
+
+impl Drop for WebSocketBudgetLease {
+    fn drop(&mut self) {
+        self.budget.release_websocket(self.owner, self.bytes);
+    }
+}
+
+fn watermark(limit: usize, percentage: u8) -> usize {
+    limit.saturating_mul(usize::from(percentage)) / 100
+}
+
+pub(super) fn control_item_reserve(limits: &WebLimitsConfig) -> usize {
+    limits
+        .max_sessions_global
+        .saturating_mul(16usize.saturating_add(limits.max_streams_per_session.saturating_mul(3)))
+}
+
+fn add_owner(values: &mut HashMap<ProfileKey, usize>, owner: ProfileKey, bytes: usize) {
+    *values.entry(owner).or_insert(0) += bytes;
+}
+
+fn remove_owner(values: &mut HashMap<ProfileKey, usize>, owner: ProfileKey, bytes: usize) {
+    let remove = if let Some(value) = values.get_mut(&owner) {
+        *value = value.saturating_sub(bytes);
+        *value == 0
+    } else {
+        false
+    };
+    if remove {
+        values.remove(&owner);
+    }
+}
+
+fn update_high_water(state: &mut BudgetState) {
+    state.high_water_bytes = state
+        .high_water_bytes
+        .max(state.queue_bytes.saturating_add(state.websocket_bytes));
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn downlink_reservation_preserves_one_uplink_and_websocket_batch() {
+        let limits = WebLimitsConfig::default();
+        let uplink_bytes = limits
+            .max_body_bytes
+            .saturating_add(limits.max_frames_per_body.saturating_mul(QUEUE_ITEM_COST));
+        let downlink_bytes = limits
+            .pending_bytes_global
+            .saturating_sub(limits.control_bytes_global)
+            .saturating_sub(uplink_bytes)
+            .saturating_sub(limits.carrier_batch_bytes);
+        let budget = WebDataBudget::new(limits);
+
+        assert!(budget.try_reserve_queue([1; 32], downlink_bytes, 1, false, true));
+        assert!(!budget.try_reserve_queue([1; 32], 1, 1, false, true));
+    }
+
+    #[test]
+    fn item_limit_rejection_does_not_request_websocket_eviction() {
+        let limits = WebLimitsConfig::default();
+        let rejected_items = limits.pending_items_global.saturating_add(1);
+        let budget = WebDataBudget::new(limits);
+        let _websocket = budget
+            .try_reserve_websocket([1; 32], 1, WebSocketBudgetClass::Data)
+            .unwrap();
+
+        assert!(!budget.try_reserve_queue([2; 32], 1, rejected_items, false, false));
+        assert!(!budget.take_pressure());
+    }
+
+    #[test]
+    fn websocket_byte_conflict_requests_pressure_eviction() {
+        let limits = WebLimitsConfig::default();
+        let data_bytes = limits
+            .pending_bytes_global
+            .saturating_sub(limits.control_bytes_global);
+        let budget = WebDataBudget::new(limits);
+        let _websocket = budget
+            .try_reserve_websocket([1; 32], 1, WebSocketBudgetClass::Data)
+            .unwrap();
+
+        assert!(!budget.try_reserve_queue([2; 32], data_bytes, 1, false, false));
+        assert!(budget.take_pressure());
+    }
+}
diff --git a/src/web/manager/lifecycle.rs b/src/web/manager/lifecycle.rs
index 2eddf77..16b0032 100644
--- a/src/web/manager/lifecycle.rs
+++ b/src/web/manager/lifecycle.rs
@@ -69,6 +69,8 @@ impl WebProcessRuntime {
     /// Stops issuance, closes all sessions, and joins bounded child work.
     pub(crate) async fn shutdown(&self) {
         self.shutdown.cancel();
+        self.close_websockets();
+        self.data_budget.close();
         let sessions = {
             let mut state = self.state.lock();
             state.closed = true;
@@ -94,15 +96,11 @@ impl WebProcessRuntime {
         let _ = tokio::time::timeout(Duration::from_secs(timeout_secs), waits).await;
         self.tasks.close();
         let _ = tokio::time::timeout(Duration::from_secs(timeout_secs), self.tasks.wait()).await;
-        let (sessions_live, streams_live, pending_bytes, pending_items) = {
+        let (sessions_live, streams_live) = {
             let state = self.state.lock();
-            (
-                state.sessions.len(),
-                state.streams_live,
-                state.pending_bytes,
-                state.pending_items,
-            )
+            (state.sessions.len(), state.streams_live)
         };
+        let budget = self.data_budget.snapshot();
         info!(
             target: "telemt::web",
             sessions_created = self.sessions_created.load(Ordering::Relaxed),
@@ -111,8 +109,10 @@ impl WebProcessRuntime {
             streams_opened = self.streams_opened.load(Ordering::Relaxed),
             streams_rejected = self.streams_rejected.load(Ordering::Relaxed),
             streams_live,
-            pending_bytes,
-            pending_items,
+            pending_bytes = budget.queue_bytes,
+            pending_items = budget.queue_items,
+            websocket_bytes = budget.websocket_bytes,
+            data_high_water_bytes = budget.high_water_bytes,
             bytes_up = self.bytes_up.load(Ordering::Relaxed),
             bytes_down = self.bytes_down.load(Ordering::Relaxed),
             limit_hits = self.limit_hits.load(Ordering::Relaxed),
@@ -122,6 +122,7 @@ impl WebProcessRuntime {
 
     /// Expires credentials and closes idle sessions without holding locks across callbacks.
     pub(super) fn cleanup(&self) {
+        self.cleanup_websockets();
         let now = Instant::now();
         let sessions = {
             let mut state = self.state.lock();
diff --git a/src/web/manager/state.rs b/src/web/manager/state.rs
index 16ae25c..b51bf7f 100644
--- a/src/web/manager/state.rs
+++ b/src/web/manager/state.rs
@@ -8,10 +8,12 @@ use sha2::{Digest, Sha256};
 use zeroize::Zeroizing;
 
 use super::{ProfileKey, TOKEN_BYTES, TokenHash};
-use crate::config::{WebLimitsConfig, WebRuntimeConfig, WebRuntimeProfile};
+use crate::config::{WebRuntimeConfig, WebRuntimeProfile};
 use crate::maestro::generation::RuntimeGeneration;
 use crate::web::session::WebSession;
 
+const WEB_PROFILE_OWNER_CONTEXT: &[u8] = b"telemt-web-profile-owner-v1\0";
+
 /// One issued bootstrap and optional idempotent session-creation replay state.
 pub(super) struct Bootstrap {
     /// Credential and replay-state expiry deadline.
@@ -74,14 +76,6 @@ pub(super) struct ManagerState {
     /// Process-wide live relay-task count.
     pub(super) streams_live: usize,
     stream_ports: HashMap<(IpAddr, SocketAddr), StreamPortState>,
-    /// Total process-wide queued byte reservation.
-    pub(super) pending_bytes: usize,
-    /// Total process-wide queued item reservation.
-    pub(super) pending_items: usize,
-    /// Portion of queued bytes charged to the control reserve.
-    pub(super) pending_control_bytes: usize,
-    /// Portion of queued items charged to the control reserve.
-    pub(super) pending_control_items: usize,
     /// Bootstrap issuance rate limiter.
     pub(super) bootstrap_rate: RateState,
     /// Session creation rate limiter.
@@ -112,9 +106,19 @@ pub(super) fn new_unique_token(
     None
 }
 
-/// Returns the precomputed capability as the stable process profile key.
+/// Derives a secret-independent quota owner stable across capability rotation.
 pub(super) fn profile_key(profile: &WebRuntimeProfile) -> ProfileKey {
-    profile.capability
+    let mut digest = Sha256::new();
+    digest.update(WEB_PROFILE_OWNER_CONTEXT);
+    digest.update((profile.host.len() as u64).to_be_bytes());
+    digest.update(profile.host.as_bytes());
+    digest.update((profile.user.len() as u64).to_be_bytes());
+    digest.update(profile.user.as_bytes());
+    digest.update([match profile.secret_mode {
+        crate::config::WebSecretMode::Plain => 0,
+        crate::config::WebSecretMode::Dd => 1,
+    }]);
+    digest.finalize().into()
 }
 
 /// Re-resolves an issued profile against the active generation without weakening identity.
@@ -211,13 +215,6 @@ where
     }
 }
 
-/// Computes the process-wide item reserve required for session control progress.
-pub(super) fn control_item_reserve(limits: &WebLimitsConfig) -> usize {
-    limits
-        .max_sessions_global
-        .saturating_mul(16usize.saturating_add(limits.max_streams_per_session.saturating_mul(3)))
-}
-
 /// Allocates a non-zero source port unique among live streams for one KDF route.
 pub(super) fn allocate_stream_port(
     state: &mut ManagerState,
diff --git a/src/web/manager/websocket.rs b/src/web/manager/websocket.rs
new file mode 100644
index 0000000..9f8cca0
--- /dev/null
+++ b/src/web/manager/websocket.rs
@@ -0,0 +1,313 @@
+use std::collections::HashMap;
+use std::net::IpAddr;
+use std::sync::Arc;
+use std::sync::atomic::{AtomicBool, AtomicU64, Ordering};
+use std::time::Duration;
+
+use tokio::sync::OwnedSemaphorePermit;
+use tokio_util::sync::CancellationToken;
+
+use super::{ManagerError, ProfileKey, WebProcessRuntime, WebSocketBudgetLease};
+
+/// One process-owned WebSocket carrier class used for eviction priority.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub(crate) enum WebSocketKind {
+    /// One connection multiplexes every logical stream in a session.
+    Multiplex,
+    /// One connection owns exactly one logical stream lane.
+    Lane(u32),
+}
+
+pub(super) struct WebSocketEntry {
+    id: u64,
+    owner: ProfileKey,
+    session_id: u64,
+    client_ip: IpAddr,
+    kind: WebSocketKind,
+    liveness_interval_ms: u64,
+    created_tick: u64,
+    last_peer_tick: AtomicU64,
+    last_progress_tick: AtomicU64,
+    opened: AtomicBool,
+    cancel: CancellationToken,
+}
+
+#[derive(Default)]
+pub(super) struct WebSocketRegistry {
+    entries: HashMap<u64, Arc<WebSocketEntry>>,
+    closed: bool,
+}
+
+/// Exact process-owned admission retained through the upgraded socket lifetime.
+pub(crate) struct WebSocketConnection {
+    runtime: std::sync::Weak<WebProcessRuntime>,
+    entry: Arc<WebSocketEntry>,
+    slot: Option<OwnedSemaphorePermit>,
+    base_budget: Option<WebSocketBudgetLease>,
+}
+
+impl WebSocketConnection {
+    /// Returns the cancellation signal used by shutdown and pressure eviction.
+    pub(crate) fn cancellation(&self) -> CancellationToken {
+        self.entry.cancel.clone()
+    }
+
+    /// Returns the process-unique connection identifier used only for debugging.
+    pub(crate) fn id(&self) -> u64 {
+        self.entry.id
+    }
+
+    /// Returns the creation-time transport liveness interval.
+    pub(crate) fn liveness_interval(&self) -> Duration {
+        Duration::from_millis(self.entry.liveness_interval_ms)
+    }
+
+    /// Marks successful ownership transfer from HTTP to the WebSocket codec.
+    pub(crate) fn mark_opened(&self) {
+        self.entry.opened.store(true, Ordering::Release);
+        self.mark_progress();
+    }
+
+    /// Refreshes the peer-liveness deadline after any received WebSocket message.
+    pub(crate) fn mark_peer_activity(&self) {
+        if let Some(runtime) = self.runtime.upgrade() {
+            let now = runtime.websocket_tick();
+            self.entry.last_peer_tick.store(now, Ordering::Release);
+            self.entry.last_progress_tick.store(now, Ordering::Release);
+        }
+    }
+
+    /// Refreshes least-recently-progressed ordering after a committed write.
+    pub(crate) fn mark_progress(&self) {
+        if let Some(runtime) = self.runtime.upgrade() {
+            self.entry
+                .last_progress_tick
+                .store(runtime.websocket_tick(), Ordering::Release);
+        }
+    }
+}
+
+impl Drop for WebSocketConnection {
+    fn drop(&mut self) {
+        if let Some(runtime) = self.runtime.upgrade() {
+            runtime.websockets.lock().entries.remove(&self.entry.id);
+            drop(self.base_budget.take());
+            drop(self.slot.take());
+            runtime.websocket_notify.notify_waiters();
+        }
+    }
+}
+
+pub(super) async fn admit(
+    runtime: &Arc<WebProcessRuntime>,
+    owner: ProfileKey,
+    session_id: u64,
+    client_ip: IpAddr,
+    kind: WebSocketKind,
+    base_bytes: usize,
+    liveness_interval: Duration,
+    eviction_timeout: Duration,
+) -> Result<WebSocketConnection, ManagerError> {
+    let liveness_interval_ms = liveness_interval.as_millis().min(u128::from(u64::MAX)) as u64;
+    if let Some(connection) = try_admit(
+        runtime,
+        owner,
+        session_id,
+        client_ip,
+        kind,
+        base_bytes,
+        liveness_interval_ms,
+    ) {
+        return Ok(connection);
+    }
+    let Some(victim) = select_victim(runtime, owner, session_id, client_ip, None) else {
+        runtime.record_limit_hit();
+        return Err(ManagerError::Limit);
+    };
+    let released = runtime.websocket_notify.notified();
+    victim.cancel.cancel();
+    let _ = tokio::time::timeout(eviction_timeout, released).await;
+    try_admit(
+        runtime,
+        owner,
+        session_id,
+        client_ip,
+        kind,
+        base_bytes,
+        liveness_interval_ms,
+    )
+    .ok_or_else(|| {
+        runtime.record_limit_hit();
+        ManagerError::Limit
+    })
+}
+
+fn try_admit(
+    runtime: &Arc<WebProcessRuntime>,
+    owner: ProfileKey,
+    session_id: u64,
+    client_ip: IpAddr,
+    kind: WebSocketKind,
+    base_bytes: usize,
+    liveness_interval_ms: u64,
+) -> Option<WebSocketConnection> {
+    let slot = Arc::clone(&runtime.websocket_connections)
+        .try_acquire_owned()
+        .ok()?;
+    let base_budget = runtime.try_websocket_base_budget(owner, base_bytes)?;
+    let id = runtime.websocket_next_id.fetch_add(1, Ordering::Relaxed);
+    let now = runtime.websocket_tick();
+    let entry = Arc::new(WebSocketEntry {
+        id,
+        owner,
+        session_id,
+        client_ip,
+        kind,
+        liveness_interval_ms,
+        created_tick: now,
+        last_peer_tick: AtomicU64::new(now),
+        last_progress_tick: AtomicU64::new(now),
+        opened: AtomicBool::new(false),
+        cancel: CancellationToken::new(),
+    });
+    let mut registry = runtime.websockets.lock();
+    if registry.closed {
+        return None;
+    }
+    registry.entries.insert(id, Arc::clone(&entry));
+    drop(registry);
+    Some(WebSocketConnection {
+        runtime: Arc::downgrade(runtime),
+        entry,
+        slot: Some(slot),
+        base_budget: Some(base_budget),
+    })
+}
+
+impl WebProcessRuntime {
+    pub(super) fn websocket_tick(&self) -> u64 {
+        self.websocket_clock.elapsed().as_millis() as u64
+    }
+
+    pub(super) fn cleanup_websockets(&self) {
+        let now = self.websocket_tick();
+        let mut victims = self
+            .websockets
+            .lock()
+            .entries
+            .values()
+            .filter(|entry| {
+                now.saturating_sub(entry.last_peer_tick.load(Ordering::Acquire))
+                    >= dead_after(entry)
+            })
+            .cloned()
+            .collect::<Vec<_>>();
+        if victims.is_empty()
+            && self.data_budget.take_pressure()
+            && let Some(victim) = select_pressure_victim(self, now)
+        {
+            victims.push(victim);
+        }
+        for victim in victims {
+            victim.cancel.cancel();
+        }
+    }
+
+    pub(super) fn close_websockets(&self) {
+        let victims = {
+            let mut registry = self.websockets.lock();
+            registry.closed = true;
+            registry.entries.values().cloned().collect::<Vec<_>>()
+        };
+        for victim in victims {
+            victim.cancel.cancel();
+        }
+    }
+}
+
+fn select_victim(
+    runtime: &WebProcessRuntime,
+    owner: ProfileKey,
+    session_id: u64,
+    client_ip: IpAddr,
+    excluded_id: Option<u64>,
+) -> Option<Arc<WebSocketEntry>> {
+    let fair_share = runtime.data_budget.fair_share(Some(owner));
+    let requester_usage = runtime.data_budget.owner_usage(owner);
+    let now = runtime.websocket_tick();
+    runtime
+        .websockets
+        .lock()
+        .entries
+        .values()
+        .filter(|entry| Some(entry.id) != excluded_id)
+        .filter_map(|entry| {
+            let owner_rank = if entry.session_id == session_id {
+                0
+            } else if entry.owner == owner {
+                1
+            } else if entry.client_ip == client_ip {
+                2
+            } else {
+                if requester_usage >= fair_share
+                    || runtime.data_budget.owner_usage(entry.owner) <= fair_share
+                {
+                    return None;
+                }
+                3
+            };
+            let priority = entry_priority(entry, now);
+            Some((
+                (
+                    owner_rank,
+                    priority,
+                    entry.last_progress_tick.load(Ordering::Acquire),
+                    entry.created_tick,
+                    entry.id,
+                ),
+                Arc::clone(entry),
+            ))
+        })
+        .min_by_key(|(key, _)| *key)
+        .map(|(_, entry)| entry)
+}
+
+fn select_pressure_victim(runtime: &WebProcessRuntime, now: u64) -> Option<Arc<WebSocketEntry>> {
+    runtime
+        .websockets
+        .lock()
+        .entries
+        .values()
+        .map(|entry| {
+            (
+                (
+                    entry_priority(entry, now),
+                    entry.last_progress_tick.load(Ordering::Acquire),
+                    entry.created_tick,
+                    entry.id,
+                ),
+                Arc::clone(entry),
+            )
+        })
+        .min_by_key(|(key, _)| *key)
+        .map(|(_, entry)| entry)
+}
+
+fn entry_priority(entry: &WebSocketEntry, now: u64) -> u8 {
+    if !entry.opened.load(Ordering::Acquire)
+        || now.saturating_sub(entry.last_peer_tick.load(Ordering::Acquire)) >= dead_after(entry)
+    {
+        0
+    } else if matches!(entry.kind, WebSocketKind::Lane(_)) {
+        1
+    } else {
+        2
+    }
+}
+
+fn dead_after(entry: &WebSocketEntry) -> u64 {
+    entry.liveness_interval_ms.saturating_mul(2)
+}
+
+#[cfg(test)]
+mod tests;
diff --git a/src/web/manager/websocket/tests.rs b/src/web/manager/websocket/tests.rs
new file mode 100644
index 0000000..6f25a3e
--- /dev/null
+++ b/src/web/manager/websocket/tests.rs
@@ -0,0 +1,40 @@
+use super::*;
+
+fn entry(kind: WebSocketKind, opened: bool, peer_tick: u64) -> WebSocketEntry {
+    WebSocketEntry {
+        id: 1,
+        owner: [0; 32],
+        session_id: 1,
+        client_ip: "192.0.2.10".parse().unwrap(),
+        kind,
+        liveness_interval_ms: 10,
+        created_tick: 1,
+        last_peer_tick: AtomicU64::new(peer_tick),
+        last_progress_tick: AtomicU64::new(peer_tick),
+        opened: AtomicBool::new(opened),
+        cancel: CancellationToken::new(),
+    }
+}
+
+#[test]
+fn preopen_and_dead_entries_precede_live_lane_and_multiplex_victims() {
+    let preopen = entry(WebSocketKind::Multiplex, false, 90);
+    let dead = entry(WebSocketKind::Multiplex, true, 1);
+    let lane = entry(WebSocketKind::Lane(7), true, 90);
+    let multiplex = entry(WebSocketKind::Multiplex, true, 90);
+
+    assert_eq!(entry_priority(&preopen, 100), 0);
+    assert_eq!(entry_priority(&dead, 100), 0);
+    assert_eq!(entry_priority(&lane, 100), 1);
+    assert_eq!(entry_priority(&multiplex, 100), 2);
+}
+
+#[test]
+fn dead_classification_keeps_each_connections_creation_time_interval() {
+    let short_interval = entry(WebSocketKind::Multiplex, true, 80);
+    let mut long_interval = entry(WebSocketKind::Multiplex, true, 80);
+    long_interval.liveness_interval_ms = 100;
+
+    assert_eq!(entry_priority(&short_interval, 100), 0);
+    assert_eq!(entry_priority(&long_interval, 100), 2);
+}
diff --git a/src/web/session.rs b/src/web/session.rs
index de0d593..48e0aa4 100644
--- a/src/web/session.rs
+++ b/src/web/session.rs
@@ -22,6 +22,9 @@ mod backend;
 mod downlink;
 // Lane carrier state isolates request sequencing and downlink replay per logical stream.
 mod lanes;
+// WebSocket carrier state owns pre-OPEN lane reservations and failure isolation.
+mod websocket;
+pub(crate) use websocket::WebSocketLaneReservation;
 // Uplink batches own exactly-once sequencing and client-frame validation.
 mod uplink;
 
@@ -107,6 +110,7 @@ struct SessionState {
     last_up_sequence: u64,
     last_up_digest: TokenHash,
     carrier_lanes: HashMap<u32, CarrierLane>,
+    websocket_lane_reservations: HashMap<u32, u16>,
     pending_bytes: usize,
     pending_items: usize,
     pending_control_bytes: usize,
@@ -183,6 +187,7 @@ impl WebSession {
                 last_up_sequence: 0,
                 last_up_digest: [0; 32],
                 carrier_lanes,
+                websocket_lane_reservations: HashMap::new(),
                 pending_bytes: 0,
                 pending_items: 0,
                 pending_control_bytes: 0,
@@ -214,6 +219,16 @@ impl WebSession {
         self.profile.carrier
     }
 
+    /// Returns the stable quota owner without exposing profile credentials.
+    pub(crate) fn profile_key(&self) -> ProfileKey {
+        self.profile_key
+    }
+
+    /// Returns the process-unique non-secret trace identifier.
+    pub(crate) fn trace_session_id(&self) -> u64 {
+        self.trace_session_id
+    }
+
     /// Returns a cloned non-secret identity only for enabled debug capture.
     pub(crate) fn trace_identity(&self) -> crate::web::trace::TraceIdentity {
         crate::web::trace::TraceIdentity::from_profile(self.trace_session_id, &self.profile)
@@ -273,12 +288,12 @@ impl WebSession {
             (data_bytes, data_items, control_bytes, control_items)
         };
         self.cancel.cancel();
-        if self.carrier() == WebCarrier::Https {
+        if self.carrier().is_multiplexed() {
             self.down_notify.notify_waiters();
         }
         if let Some(manager) = self.manager.upgrade() {
-            manager.release_pending(data_bytes, data_items, false);
-            manager.release_pending(control_bytes, control_items, true);
+            manager.release_pending(self.profile_key, data_bytes, data_items, false);
+            manager.release_pending(self.profile_key, control_bytes, control_items, true);
             if !self.finished.swap(true, Ordering::AcqRel) {
                 self.trace_lifecycle(
                     crate::web::trace::TraceLifecycleEvent::SessionClosed,
@@ -394,7 +409,7 @@ impl WebSession {
         stream.send_credit -= count as u64;
         state.last_activity = Instant::now();
         drop(state);
-        if self.carrier() == WebCarrier::Https {
+        if self.carrier().is_multiplexed() {
             self.down_notify.notify_waiters();
         }
         Poll::Ready(Ok(count))
diff --git a/src/web/session/backend.rs b/src/web/session/backend.rs
index 64d2633..2152833 100644
--- a/src/web/session/backend.rs
+++ b/src/web/session/backend.rs
@@ -1,6 +1,6 @@
 use std::io;
 use std::sync::Arc;
-use std::sync::atomic::Ordering;
+use std::sync::atomic::{AtomicBool, Ordering};
 use std::time::Duration;
 
 use crate::proxy::shared_state::ConntrackClosePolicy;
@@ -15,10 +15,15 @@ mod tests;
 
 impl WebSession {
     /// Starts one owned inner handshake and relay task for an admitted stream.
-    pub(super) fn spawn_stream(self: &Arc<Self>, stream_id: u32, peer_port: u16) {
+    pub(super) fn spawn_stream(
+        self: &Arc<Self>,
+        stream_id: u32,
+        peer_port: u16,
+        retain_reservation_on_reject: bool,
+    ) -> bool {
         let Some(manager) = self.manager.upgrade() else {
-            self.stream_finished(stream_id, peer_port);
-            return;
+            self.stream_rejected_before_spawn(stream_id, peer_port, retain_reservation_on_reject);
+            return false;
         };
         let generation = manager.active_generation();
         if !*generation.admission_rx.borrow() {
@@ -27,8 +32,8 @@ impl WebSession {
                 Some(stream_id),
                 Some("admission_closed"),
             );
-            self.stream_finished(stream_id, peer_port);
-            return;
+            self.stream_rejected_before_spawn(stream_id, peer_port, retain_reservation_on_reject);
+            return false;
         }
         let Ok(connection_permit) = generation.max_connections.clone().try_acquire_owned() else {
             manager.record_stream_rejected();
@@ -37,21 +42,24 @@ impl WebSession {
                 Some(stream_id),
                 Some("connection_limit"),
             );
-            self.stream_finished(stream_id, peer_port);
-            return;
+            self.stream_rejected_before_spawn(stream_id, peer_port, retain_reservation_on_reject);
+            return false;
         };
         let deps = generation.client_runtime_deps();
         let replay_checker = Arc::clone(&generation.replay_checker);
         let session = Arc::clone(self);
         let cancel = self.cancel.clone();
+        let retain_rejected = Arc::new(AtomicBool::new(false));
         self.tasks_live.fetch_add(1, Ordering::AcqRel);
-        let spawned = generation.spawn_session(async move {
+        let completion = StreamCompletion {
+            session: Arc::clone(&session),
+            stream_id,
+            peer_port,
+            retain_rejected: Arc::clone(&retain_rejected),
+        };
+        let future = async move {
             let _connection_permit = connection_permit;
-            let _completion = StreamCompletion {
-                session: Arc::clone(&session),
-                stream_id,
-                peer_port,
-            };
+            let _completion = completion;
             session.trace_lifecycle(
                 crate::web::trace::TraceLifecycleEvent::StreamAdmitted,
                 Some(stream_id),
@@ -69,16 +77,41 @@ impl WebSession {
                     peer_port,
                 ) => {}
             }
-        });
-        if !spawned {
+        };
+        if let Err(future) = generation.try_spawn_session(future) {
+            retain_rejected.store(retain_reservation_on_reject, Ordering::Release);
             self.trace_lifecycle(
                 crate::web::trace::TraceLifecycleEvent::StreamRejected,
                 Some(stream_id),
                 Some("generation_closed"),
             );
-            self.tasks_live.fetch_sub(1, Ordering::AcqRel);
+            drop(future);
+            return false;
+        }
+        true
+    }
+
+    fn stream_rejected_before_spawn(
+        &self,
+        stream_id: u32,
+        peer_port: u16,
+        retain_reservation: bool,
+    ) {
+        if !retain_reservation {
             self.stream_finished(stream_id, peer_port);
-            self.tasks_done.notify_waiters();
+            return;
+        }
+        let queued = {
+            let mut state = self.state.lock();
+            state.streams.remove(&stream_id).map(|stream| {
+                let (bytes, items) = inbound_queue_cost(&stream.inbound);
+                self.release_locked(&mut state, bytes, items, false);
+                self.remember_closed_locked(&mut state, stream_id);
+                self.queue_control_locked(&mut state, FrameType::Close, stream_id, &[])
+            })
+        };
+        if queued.is_some_and(|queued| !queued) {
+            self.close();
         }
     }
 
@@ -106,7 +139,7 @@ impl WebSession {
             if !queued {
                 self.close();
             }
-            if self.carrier() == crate::config::WebCarrier::Https {
+            if self.carrier().is_multiplexed() {
                 self.down_notify.notify_waiters();
             }
         }
@@ -117,6 +150,7 @@ struct StreamCompletion {
     session: Arc<WebSession>,
     stream_id: u32,
     peer_port: u16,
+    retain_rejected: Arc<AtomicBool>,
 }
 
 impl Drop for StreamCompletion {
@@ -126,7 +160,12 @@ impl Drop for StreamCompletion {
             Some(self.stream_id),
             None,
         );
-        self.session.stream_finished(self.stream_id, self.peer_port);
+        if self.retain_rejected.load(Ordering::Acquire) {
+            self.session
+                .stream_rejected_before_spawn(self.stream_id, self.peer_port, true);
+        } else {
+            self.session.stream_finished(self.stream_id, self.peer_port);
+        }
         if self.session.tasks_live.fetch_sub(1, Ordering::AcqRel) == 1 {
             self.session.tasks_done.notify_waiters();
         }
@@ -263,6 +302,10 @@ async fn run_stream(
     session.trace_lifecycle(
         crate::web::trace::TraceLifecycleEvent::RelayEnded,
         Some(stream_id),
-        Some(if relay_result.is_ok() { "completed" } else { "error" }),
+        Some(if relay_result.is_ok() {
+            "completed"
+        } else {
+            "error"
+        }),
     );
 }
diff --git a/src/web/session/backend_tests.rs b/src/web/session/backend_tests.rs
index 56fb65c..47adb25 100644
--- a/src/web/session/backend_tests.rs
+++ b/src/web/session/backend_tests.rs
@@ -13,9 +13,7 @@ use crate::config::{
     WebSecretMode,
 };
 use crate::crypto::{AesCtr, sha256};
-use crate::maestro::generation::{
-    RuntimeGeneration, test_runtime_generation_with_admission,
-};
+use crate::maestro::generation::{RuntimeGeneration, test_runtime_generation_with_admission};
 use crate::protocol::constants::{
     DC_IDX_POS, HANDSHAKE_LEN, IV_LEN, PREKEY_LEN, PROTO_TAG_POS, ProtoTag, SKIP_LEN,
 };
@@ -39,10 +37,11 @@ impl TestRuntime {
     ) -> Result<u64, ManagerError> {
         let encoded = frame::encode(frame_type, stream_id, payload);
         match self.session.carrier() {
-            WebCarrier::Https => self.session.process_up(sequence, &encoded),
-            WebCarrier::HttpsLanes => {
-                self.session
-                    .process_up_lane(stream_id, sequence, &encoded)
+            WebCarrier::Https | WebCarrier::Websocket => {
+                self.session.process_up(sequence, &encoded)
+            }
+            WebCarrier::HttpsLanes | WebCarrier::WebsocketLanes => {
+                self.session.process_up_lane(stream_id, sequence, &encoded)
             }
         }
     }
@@ -152,8 +151,7 @@ fn valid_plain_handshake() -> [u8; HANDSHAKE_LEN] {
     let mut cipher = AesCtr::new(&dec_key, u128::from_be_bytes(dec_iv));
     let keystream = cipher.encrypt(&[0u8; HANDSHAKE_LEN]);
     let mut plaintext = [0u8; HANDSHAKE_LEN];
-    plaintext[PROTO_TAG_POS..PROTO_TAG_POS + 4]
-        .copy_from_slice(&ProtoTag::Intermediate.to_bytes());
+    plaintext[PROTO_TAG_POS..PROTO_TAG_POS + 4].copy_from_slice(&ProtoTag::Intermediate.to_bytes());
     plaintext[DC_IDX_POS..DC_IDX_POS + 2].copy_from_slice(&2i16.to_le_bytes());
     for index in PROTO_TAG_POS..HANDSHAKE_LEN {
         handshake[index] = plaintext[index] ^ keystream[index];
diff --git a/src/web/session/downlink.rs b/src/web/session/downlink.rs
index a6ef00e..2ac3e64 100644
--- a/src/web/session/downlink.rs
+++ b/src/web/session/downlink.rs
@@ -5,14 +5,13 @@ use bytes::{BufMut, Bytes, BytesMut};
 use super::{
     DownBatch, PendingClass, PollResult, QUEUE_ITEM_COST, QueuedFrame, SessionState, WebSession,
 };
-use crate::config::WebCarrier;
 use crate::web::frame::{self, FrameType};
 use crate::web::manager::ManagerError;
 
 impl WebSession {
     /// Polls pending downlink frames with cursor replay and newest-poll-wins semantics.
     pub(crate) async fn poll_down(&self, cursor: u64) -> Result<PollResult, ManagerError> {
-        if self.carrier() != WebCarrier::Https {
+        if !self.carrier().is_multiplexed() {
             return Err(ManagerError::Protocol);
         }
         let epoch = {
@@ -167,7 +166,13 @@ impl WebSession {
         let Some(manager) = self.manager.upgrade() else {
             return false;
         };
-        if !manager.try_reserve_pending(bytes, items, control, class == PendingClass::Downlink) {
+        if !manager.try_reserve_pending(
+            self.profile_key,
+            bytes,
+            items,
+            control,
+            class == PendingClass::Downlink,
+        ) {
             return false;
         }
         state.pending_bytes += bytes;
@@ -194,7 +199,7 @@ impl WebSession {
             state.pending_control_items = state.pending_control_items.saturating_sub(items);
         }
         if let Some(manager) = self.manager.upgrade() {
-            manager.release_pending(bytes, items, control);
+            manager.release_pending(self.profile_key, bytes, items, control);
         }
     }
 
@@ -208,7 +213,7 @@ impl WebSession {
         if amount == 0 {
             return true;
         }
-        if self.carrier() == WebCarrier::HttpsLanes {
+        if self.carrier().uses_lanes() {
             return self.queue_control_locked(
                 state,
                 FrameType::Window,
@@ -257,7 +262,7 @@ impl WebSession {
         stream_id: u32,
         payload: &[u8],
     ) -> bool {
-        if self.carrier() == WebCarrier::HttpsLanes {
+        if self.carrier().uses_lanes() {
             return self.queue_frame_locked(state, FrameType::Data, stream_id, payload, false);
         }
         let can_coalesce = state.pending_frames.back().is_some_and(|last| {
@@ -290,7 +295,7 @@ impl WebSession {
         payload: &[u8],
         control: bool,
     ) -> bool {
-        if self.carrier() == WebCarrier::HttpsLanes {
+        if self.carrier().uses_lanes() {
             return self.queue_lane_frame_locked(state, frame_type, stream_id, payload, control);
         }
         let cost = frame::HEADER_BYTES + payload.len() + QUEUE_ITEM_COST;
@@ -409,7 +414,9 @@ mod tests {
     use std::net::SocketAddr;
     use std::sync::Arc;
 
-    use crate::config::{WebLimitsConfig, WebRuntimeProfile, WebSecretMode, WebTimeoutsConfig};
+    use crate::config::{
+        WebCarrier, WebLimitsConfig, WebRuntimeProfile, WebSecretMode, WebTimeoutsConfig,
+    };
     use crate::web::manager::WebProcessRuntime;
 
     fn session() -> Arc<WebSession> {
diff --git a/src/web/session/lanes.rs b/src/web/session/lanes.rs
index 00f2de7..7589348 100644
--- a/src/web/session/lanes.rs
+++ b/src/web/session/lanes.rs
@@ -113,6 +113,7 @@ impl WebSession {
                 &mut state,
                 &frames,
                 &mut opened,
+                &mut None,
                 &mut unused_bytes,
                 &mut unused_items,
             );
@@ -137,7 +138,7 @@ impl WebSession {
             return result;
         }
         for (stream_id, peer_port) in opened {
-            self.spawn_stream(stream_id, peer_port);
+            self.spawn_stream(stream_id, peer_port, false);
         }
         if let Some(manager) = self.manager.upgrade() {
             manager.record_up(body.len());
@@ -151,7 +152,7 @@ impl WebSession {
         lane_id: u32,
         cursor: u64,
     ) -> Result<PollResult, ManagerError> {
-        if self.carrier() != WebCarrier::HttpsLanes || lane_id > frame::MAX_STREAM_ID {
+        if !self.carrier().uses_lanes() || lane_id > frame::MAX_STREAM_ID {
             return Err(ManagerError::Protocol);
         }
         let (epoch, notify) = {
@@ -404,7 +405,7 @@ impl WebSession {
 
     pub(super) fn remember_closed_locked(&self, state: &mut SessionState, stream_id: u32) {
         let evicted = remember_closed(state, stream_id, self.limits.max_tombstones_per_session);
-        if self.carrier() != WebCarrier::HttpsLanes {
+        if !self.carrier().uses_lanes() {
             return;
         }
         if let Some(evicted) = evicted {
@@ -415,7 +416,7 @@ impl WebSession {
         }
     }
 
-    fn release_lane_locked(&self, state: &mut SessionState, lane_id: u32) {
+    pub(super) fn release_lane_locked(&self, state: &mut SessionState, lane_id: u32) {
         let Some(mut lane) = state.carrier_lanes.remove(&lane_id) else {
             return;
         };
diff --git a/src/web/session/uplink.rs b/src/web/session/uplink.rs
index be30eb5..3049109 100644
--- a/src/web/session/uplink.rs
+++ b/src/web/session/uplink.rs
@@ -11,7 +11,6 @@ use super::{
     InboundChunk, PendingClass, QUEUE_ITEM_COST, SessionState, StreamState, WebSession,
     inbound_queue_cost,
 };
-use crate::config::WebCarrier;
 use crate::web::frame::{self, Frame, FrameType};
 use crate::web::manager::{ManagerError, TokenHash};
 
@@ -22,7 +21,7 @@ impl WebSession {
         sequence: u64,
         body: &[u8],
     ) -> Result<u64, ManagerError> {
-        if self.carrier() != WebCarrier::Https {
+        if !self.carrier().is_multiplexed() {
             return Err(ManagerError::Protocol);
         }
         if self
@@ -90,6 +89,7 @@ impl WebSession {
                 &mut state,
                 &frames,
                 &mut opened,
+                &mut None,
                 &mut unused_bytes,
                 &mut unused_items,
             );
@@ -113,7 +113,7 @@ impl WebSession {
             return result;
         }
         for (stream_id, peer_port) in opened {
-            self.spawn_stream(stream_id, peer_port);
+            self.spawn_stream(stream_id, peer_port, false);
         }
         if let Some(manager) = self.manager.upgrade() {
             manager.record_up(body.len());
@@ -126,6 +126,7 @@ impl WebSession {
         state: &mut SessionState,
         frames: &[Frame<'_>],
         opened: &mut Vec<(u32, u16)>,
+        reserved_open: &mut Option<(u32, u16)>,
         unused_bytes: &mut usize,
         unused_items: &mut usize,
     ) -> bool {
@@ -136,13 +137,31 @@ impl WebSession {
             let was_closed = state.closed_streams.contains(&value.stream_id);
             match value.frame_type {
                 FrameType::Open => {
-                    let Some(peer_port) = self.reserve_stream_locked(state) else {
-                        self.remember_closed_locked(state, value.stream_id);
-                        if !self.queue_control_locked(state, FrameType::Close, value.stream_id, &[])
+                    let peer_port = match reserved_open.take() {
+                        Some((reserved_stream_id, peer_port))
+                            if reserved_stream_id == value.stream_id =>
                         {
+                            peer_port
+                        }
+                        Some(reserved) => {
+                            *reserved_open = Some(reserved);
                             return false;
                         }
-                        continue;
+                        None => {
+                            let Some(peer_port) = self.reserve_stream_locked(state) else {
+                                self.remember_closed_locked(state, value.stream_id);
+                                if !self.queue_control_locked(
+                                    state,
+                                    FrameType::Close,
+                                    value.stream_id,
+                                    &[],
+                                ) {
+                                    return false;
+                                }
+                                continue;
+                            };
+                            peer_port
+                        }
                     };
                     state.streams.insert(
                         value.stream_id,
@@ -331,7 +350,9 @@ mod tests {
     use super::*;
     use std::net::SocketAddr;
 
-    use crate::config::{WebLimitsConfig, WebRuntimeProfile, WebSecretMode, WebTimeoutsConfig};
+    use crate::config::{
+        WebCarrier, WebLimitsConfig, WebRuntimeProfile, WebSecretMode, WebTimeoutsConfig,
+    };
     use crate::web::manager::WebProcessRuntime;
 
     fn session() -> Arc<WebSession> {
diff --git a/src/web/session/websocket.rs b/src/web/session/websocket.rs
new file mode 100644
index 0000000..ea7ee7d
--- /dev/null
+++ b/src/web/session/websocket.rs
@@ -0,0 +1,250 @@
+use std::sync::Arc;
+use std::time::Instant;
+
+use sha2::{Digest, Sha256};
+
+use super::uplink::{inbound_reservation, validate_batch};
+use super::{CarrierLane, PendingClass, WebSession, inbound_queue_cost};
+use crate::config::WebCarrier;
+use crate::web::frame;
+use crate::web::manager::ManagerError;
+
+/// Pre-OPEN stream quota and synthetic tuple ownership for one WebSocket lane.
+pub(crate) struct WebSocketLaneReservation {
+    session: Arc<WebSession>,
+    lane_id: u32,
+    peer_port: u16,
+    transferred: bool,
+}
+
+impl WebSocketLaneReservation {
+    /// Returns the logical stream owned by this connection.
+    pub(crate) fn lane_id(&self) -> u32 {
+        self.lane_id
+    }
+
+    fn transfer_to_stream(&mut self) {
+        let removed = self
+            .session
+            .state
+            .lock()
+            .websocket_lane_reservations
+            .remove(&self.lane_id);
+        if removed == Some(self.peer_port) {
+            self.transferred = true;
+        }
+    }
+}
+
+impl Drop for WebSocketLaneReservation {
+    fn drop(&mut self) {
+        if !self.transferred {
+            self.session
+                .release_websocket_lane_reservation(self.lane_id, self.peer_port);
+        }
+    }
+}
+
+impl WebSession {
+    /// Acquires stream quota and tuple ownership before a lane returns HTTP 101.
+    pub(crate) fn reserve_websocket_lane(
+        self: &Arc<Self>,
+        lane_id: u32,
+    ) -> Result<WebSocketLaneReservation, ManagerError> {
+        if self.carrier() != WebCarrier::WebsocketLanes
+            || lane_id == 0
+            || lane_id > frame::MAX_STREAM_ID
+        {
+            return Err(ManagerError::Protocol);
+        }
+        let mut state = self.state.lock();
+        if state.closed {
+            return Err(ManagerError::Closed);
+        }
+        if state.active_peer_ports.len() >= self.profile.max_streams_per_session
+            || state.streams.contains_key(&lane_id)
+            || state.closed_streams.contains(&lane_id)
+            || state.websocket_lane_reservations.contains_key(&lane_id)
+        {
+            return Err(ManagerError::Limit);
+        }
+        let Some(manager) = self.manager.upgrade() else {
+            return Err(ManagerError::Closed);
+        };
+        let Some(peer_port) = manager.try_acquire_stream(
+            self.profile_key,
+            self.profile.max_streams,
+            self.client_ip,
+            self.profile.public_addr,
+        ) else {
+            return Err(ManagerError::Limit);
+        };
+        if !state.active_peer_ports.insert(peer_port) {
+            manager.release_stream(
+                self.profile_key,
+                self.client_ip,
+                self.profile.public_addr,
+                peer_port,
+            );
+            return Err(ManagerError::Limit);
+        }
+        state.websocket_lane_reservations.insert(lane_id, peer_port);
+        state.carrier_lanes.insert(lane_id, CarrierLane::new());
+        Ok(WebSocketLaneReservation {
+            session: Arc::clone(self),
+            lane_id,
+            peer_port,
+            transferred: false,
+        })
+    }
+
+    /// Applies one ordered WebSocket lane message without closing sibling lanes.
+    pub(crate) fn process_websocket_lane(
+        self: &Arc<Self>,
+        reservation: &mut WebSocketLaneReservation,
+        sequence: u64,
+        body: &[u8],
+    ) -> Result<(), ManagerError> {
+        if !Arc::ptr_eq(self, &reservation.session)
+            || reservation.lane_id == 0
+            || reservation.lane_id > frame::MAX_STREAM_ID
+        {
+            return Err(ManagerError::Protocol);
+        }
+        let lane_id = reservation.lane_id;
+        let frames = frame::parse_all(body, &self.limits).map_err(|_| ManagerError::Protocol)?;
+        if frames
+            .iter()
+            .copied()
+            .any(|value| value.stream_id != lane_id || frame::validate_client_shape(value).is_err())
+        {
+            return Err(ManagerError::Protocol);
+        }
+        let digest = Sha256::digest(body).into();
+        let mut opened = Vec::new();
+        let result = {
+            let mut state = self.state.lock();
+            if state.closed {
+                return Err(ManagerError::Closed);
+            }
+            if !reservation.transferred
+                && state.websocket_lane_reservations.get(&lane_id) != Some(&reservation.peer_port)
+            {
+                return Err(ManagerError::Closed);
+            }
+            let Some(lane) = state.carrier_lanes.get_mut(&lane_id) else {
+                return Err(ManagerError::Closed);
+            };
+            if sequence == 0 || sequence != lane.last_up_sequence.saturating_add(1) {
+                return Err(ManagerError::Protocol);
+            }
+            if lane.up_active {
+                return Err(ManagerError::Concurrent);
+            }
+            lane.up_active = true;
+            if !validate_batch(&state, &frames) {
+                if let Some(lane) = state.carrier_lanes.get_mut(&lane_id) {
+                    lane.up_active = false;
+                }
+                return Err(ManagerError::Protocol);
+            }
+            let (reserve_bytes, reserve_items) = inbound_reservation(&state, &frames);
+            if !self.reserve_locked(
+                &mut state,
+                reserve_bytes,
+                reserve_items,
+                PendingClass::Uplink,
+            ) {
+                if let Some(lane) = state.carrier_lanes.get_mut(&lane_id) {
+                    lane.up_active = false;
+                }
+                return Err(ManagerError::Backpressure);
+            }
+            let mut unused_bytes = reserve_bytes;
+            let mut unused_items = reserve_items;
+            let mut reserved_open =
+                (!reservation.transferred).then_some((lane_id, reservation.peer_port));
+            let applied = self.apply_batch_locked(
+                &mut state,
+                &frames,
+                &mut opened,
+                &mut reserved_open,
+                &mut unused_bytes,
+                &mut unused_items,
+            );
+            self.release_locked(&mut state, unused_bytes, unused_items, false);
+            if let Some(lane) = state.carrier_lanes.get_mut(&lane_id) {
+                lane.up_active = false;
+                if applied {
+                    lane.last_up_sequence = sequence;
+                    lane.last_up_digest = digest;
+                }
+            }
+            state.last_activity = Instant::now();
+            applied.then_some(()).ok_or(ManagerError::Protocol)
+        };
+        result?;
+        for (stream_id, peer_port) in opened {
+            if stream_id != lane_id || peer_port != reservation.peer_port {
+                return Err(ManagerError::Protocol);
+            }
+            if !self.spawn_stream(stream_id, peer_port, true) {
+                return Err(ManagerError::Limit);
+            }
+            reservation.transfer_to_stream();
+        }
+        if !reservation.transferred {
+            return Err(ManagerError::Protocol);
+        }
+        if let Some(manager) = self.manager.upgrade() {
+            manager.record_up(body.len());
+        }
+        Ok(())
+    }
+
+    /// Ends one failed or disconnected lane without closing its parent session.
+    pub(crate) fn close_websocket_lane(&self, lane_id: u32) {
+        let reserved = {
+            let mut state = self.state.lock();
+            let reserved = state.websocket_lane_reservations.remove(&lane_id);
+            if let Some(stream) = state.streams.remove(&lane_id) {
+                let (bytes, items) = inbound_queue_cost(&stream.inbound);
+                self.release_locked(&mut state, bytes, items, false);
+                if let Some(waker) = stream.read_waker {
+                    waker.wake();
+                }
+                if let Some(waker) = stream.write_waker {
+                    waker.wake();
+                }
+            }
+            self.remember_closed_locked(&mut state, lane_id);
+            self.release_lane_locked(&mut state, lane_id);
+            reserved
+        };
+        if let Some(peer_port) = reserved {
+            self.release_websocket_lane_reservation(lane_id, peer_port);
+        }
+    }
+
+    fn release_websocket_lane_reservation(&self, lane_id: u32, peer_port: u16) {
+        let removed = {
+            let mut state = self.state.lock();
+            if state.websocket_lane_reservations.get(&lane_id) == Some(&peer_port) {
+                state.websocket_lane_reservations.remove(&lane_id);
+            }
+            self.release_lane_locked(&mut state, lane_id);
+            state.active_peer_ports.remove(&peer_port)
+        };
+        if removed && let Some(manager) = self.manager.upgrade() {
+            manager.release_stream(
+                self.profile_key,
+                self.client_ip,
+                self.profile.public_addr,
+                peer_port,
+            );
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests;
diff --git a/src/web/session/websocket/tests.rs b/src/web/session/websocket/tests.rs
new file mode 100644
index 0000000..bc97dad
--- /dev/null
+++ b/src/web/session/websocket/tests.rs
@@ -0,0 +1,135 @@
+use std::collections::BTreeMap;
+use std::sync::Arc;
+
+use arc_swap::ArcSwap;
+use tokio::sync::watch;
+
+use super::*;
+use crate::config::{ProxyConfig, WebRuntimeConfig, WebRuntimeProfile, WebSecretMode};
+use crate::maestro::generation::{RuntimeGeneration, test_runtime_generation_with_admission};
+use crate::web::frame::FrameType;
+use crate::web::manager::WebProcessRuntime;
+
+struct TestRuntime {
+    session: Arc<WebSession>,
+    manager: Arc<WebProcessRuntime>,
+    generation: Arc<RuntimeGeneration>,
+}
+
+impl TestRuntime {
+    async fn shutdown(self) {
+        self.session.close();
+        self.session.wait().await;
+        self.manager.shutdown().await;
+        self.generation.stop_sessions().await;
+        self.generation.stop_background_tasks().await;
+    }
+}
+
+fn runtime(admission: bool) -> TestRuntime {
+    let profile = Arc::new(WebRuntimeProfile {
+        host: "proxy.example.com".to_string(),
+        public_addr: "203.0.113.10:443".parse().unwrap(),
+        user: "default".to_string(),
+        secret_mode: WebSecretMode::Plain,
+        carrier: WebCarrier::WebsocketLanes,
+        capability: [7; 32],
+        key_fingerprint: "0000000000000000".to_string(),
+        max_sessions: 2,
+        max_streams: 1,
+        max_streams_per_session: 1,
+    });
+    let mut config = ProxyConfig::default();
+    config.web.enabled = true;
+    config.web.carrier = WebCarrier::WebsocketLanes;
+    config.web.timeouts.shutdown_secs = 1;
+    config.web.runtime = Some(Arc::new(WebRuntimeConfig {
+        vhosts: BTreeMap::new(),
+        profiles: vec![Arc::clone(&profile)],
+    }));
+    config.rebuild_runtime_user_auth().unwrap();
+    let limits = config.web.limits.clone();
+    let timeouts = config.web.timeouts.clone();
+    let (_admission_tx, admission_rx) = watch::channel(admission);
+    let generation = test_runtime_generation_with_admission(1, config, admission_rx);
+    let manager = WebProcessRuntime::start(Arc::new(ArcSwap::from(Arc::clone(&generation))));
+    let session = WebSession::new(
+        Arc::downgrade(&manager),
+        [8; 32],
+        "192.0.2.10".parse().unwrap(),
+        1,
+        profile,
+        [7; 32],
+        limits,
+        timeouts,
+    );
+    TestRuntime {
+        session,
+        manager,
+        generation,
+    }
+}
+
+#[tokio::test]
+async fn rejected_open_retains_stream_quota_until_lane_socket_teardown() {
+    let runtime = runtime(false);
+    let mut reservation = runtime.session.reserve_websocket_lane(7).unwrap();
+    let open = frame::encode(FrameType::Open, 7, &[]);
+
+    assert_eq!(
+        runtime
+            .session
+            .process_websocket_lane(&mut reservation, 1, &open),
+        Err(ManagerError::Limit),
+    );
+    assert!(
+        runtime
+            .manager
+            .try_acquire_stream(
+                runtime.session.profile_key,
+                runtime.session.profile.max_streams,
+                runtime.session.client_ip,
+                runtime.session.profile.public_addr,
+            )
+            .is_none()
+    );
+
+    runtime.session.close_websocket_lane(7);
+    drop(reservation);
+    let peer_port = runtime
+        .manager
+        .try_acquire_stream(
+            runtime.session.profile_key,
+            runtime.session.profile.max_streams,
+            runtime.session.client_ip,
+            runtime.session.profile.public_addr,
+        )
+        .unwrap();
+    runtime.manager.release_stream(
+        runtime.session.profile_key,
+        runtime.session.client_ip,
+        runtime.session.profile.public_addr,
+        peer_port,
+    );
+    runtime.shutdown().await;
+}
+
+#[tokio::test]
+async fn malformed_lane_message_does_not_close_sibling_session_state() {
+    let runtime = runtime(true);
+    let mut reservation = runtime.session.reserve_websocket_lane(7).unwrap();
+    let data = frame::encode(FrameType::Data, 7, &[1]);
+
+    assert_eq!(
+        runtime
+            .session
+            .process_websocket_lane(&mut reservation, 1, &data),
+        Err(ManagerError::Protocol),
+    );
+    assert!(!runtime.session.state.lock().closed);
+
+    runtime.session.close_websocket_lane(7);
+    drop(reservation);
+    assert!(runtime.session.reserve_websocket_lane(8).is_ok());
+    runtime.shutdown().await;
+}
diff --git a/src/web/trace/exchange.rs b/src/web/trace/exchange.rs
index ab46582..6fa0a92 100644
--- a/src/web/trace/exchange.rs
+++ b/src/web/trace/exchange.rs
@@ -139,7 +139,10 @@ impl HttpTraceExchange {
 
     /// Binds non-secret profile and process session identity.
     pub(crate) fn bind_profile(&self, profile: &WebRuntimeProfile, session_id: u64) {
-        let dynamic = profile.user.len().saturating_add(profile.key_fingerprint.len());
+        let dynamic = profile
+            .user
+            .len()
+            .saturating_add(profile.key_fingerprint.len());
         let mut state = self.state.lock();
         state.identity.session_id = Some(session_id);
         if self.reserve(dynamic) {
@@ -150,12 +153,11 @@ impl HttpTraceExchange {
 
     /// Binds an already resolved non-secret session identity.
     pub(crate) fn bind_identity(&self, identity: TraceIdentity) {
-        let dynamic = identity.user.as_ref().map_or(0, String::len).saturating_add(
-            identity
-                .key_fingerprint
-                .as_ref()
-                .map_or(0, String::len),
-        );
+        let dynamic = identity
+            .user
+            .as_ref()
+            .map_or(0, String::len)
+            .saturating_add(identity.key_fingerprint.as_ref().map_or(0, String::len));
         let mut state = self.state.lock();
         state.identity.session_id = identity.session_id;
         if self.reserve(dynamic) {
@@ -223,11 +225,8 @@ impl HttpTraceExchange {
             body.truncated |= !data.is_empty();
             return;
         }
-        let Some(limit) = capture_limit(
-            &self.policy,
-            route,
-            self.store.max_carrier_body_bytes(),
-        ) else {
+        let Some(limit) = capture_limit(&self.policy, route, self.store.max_carrier_body_bytes())
+        else {
             return;
         };
         if body.captured.len() >= limit {
@@ -267,7 +266,9 @@ impl HttpTraceExchange {
         if self.policy.capture_timings {
             match direction {
                 TraceDirection::Request => state.timings.request_body_us = Some(self.elapsed_us()),
-                TraceDirection::Response => state.timings.response_body_us = Some(self.elapsed_us()),
+                TraceDirection::Response => {
+                    state.timings.response_body_us = Some(self.elapsed_us())
+                }
             }
         }
         drop(state);
@@ -386,10 +387,7 @@ impl HttpTraceExchange {
     }
 
     fn elapsed_us(&self) -> u64 {
-        self.started
-            .elapsed()
-            .as_micros()
-            .min(u128::from(u64::MAX)) as u64
+        self.started.elapsed().as_micros().min(u128::from(u64::MAX)) as u64
     }
 }
 
@@ -402,10 +400,7 @@ impl Drop for HttpTraceExchange {
     }
 }
 
-fn body_snapshot(
-    policy: &WebDebugConfig,
-    body: &mut BodyCapture,
-) -> Option<TraceBodySnapshot> {
+fn body_snapshot(policy: &WebDebugConfig, body: &mut BodyCapture) -> Option<TraceBodySnapshot> {
     (policy.body_capture != WebDebugBodyCapture::Off).then(|| TraceBodySnapshot {
         observed_bytes: body.observed_bytes,
         captured: std::mem::take(&mut body.captured),
@@ -475,7 +470,12 @@ mod tests {
         let request_body = http.request_body.as_ref().unwrap();
         let response_body = http.response_body.as_ref().unwrap();
         for secret in [request_token.as_bytes(), capability.as_bytes()] {
-            assert!(!request_body.captured.windows(secret.len()).any(|value| value == secret));
+            assert!(
+                !request_body
+                    .captured
+                    .windows(secret.len())
+                    .any(|value| value == secret)
+            );
         }
         assert!(
             !response_body
diff --git a/src/web/trace/mod.rs b/src/web/trace/mod.rs
index 6376486..3398998 100644
--- a/src/web/trace/mod.rs
+++ b/src/web/trace/mod.rs
@@ -12,6 +12,6 @@ mod types;
 pub(crate) use exchange::HttpTraceExchange;
 pub(crate) use store::{StoredTraceRecord, WebTraceStore, epoch_millis as store_epoch_millis};
 pub(crate) use types::{
-    TraceBodySnapshot, TraceBodyState, TraceDirection, TraceHeader, TraceIdentity,
-    TraceLifecycleEvent, TraceRecord, TraceRecordKind, TraceRoute,
+    TraceBodySnapshot, TraceBodyState, TraceDirection, TraceFrame, TraceHeader, TraceIdentity,
+    TraceLifecycleEvent, TraceRecord, TraceRecordKind, TraceRoute, TraceWebSocketContext,
 };
diff --git a/src/web/trace/sanitize.rs b/src/web/trace/sanitize.rs
index 9a8dd71..7067654 100644
--- a/src/web/trace/sanitize.rs
+++ b/src/web/trace/sanitize.rs
@@ -24,7 +24,9 @@ pub(super) fn request_dynamic_bytes<B>(
             request
                 .headers()
                 .get(header::USER_AGENT)
-                .map_or(0, |value| lossy_text_reservation(value.as_bytes(), USER_AGENT_MAX_BYTES)),
+                .map_or(0, |value| {
+                    lossy_text_reservation(value.as_bytes(), USER_AGENT_MAX_BYTES)
+                }),
         )
         .saturating_add(
             policy
@@ -56,8 +58,7 @@ pub(super) fn sanitized_headers(headers: &hyper::HeaderMap) -> Vec<TraceHeader>
         .iter()
         .map(|(name, value)| TraceHeader {
             name: name.as_str().to_string(),
-            value: header_value_allowed(name)
-                .then(|| bounded_text(value.as_bytes(), 4096)),
+            value: header_value_allowed(name).then(|| bounded_text(value.as_bytes(), 4096)),
         })
         .collect()
 }
diff --git a/src/web/trace/store.rs b/src/web/trace/store.rs
index 4d5350e..222e29a 100644
--- a/src/web/trace/store.rs
+++ b/src/web/trace/store.rs
@@ -13,6 +13,9 @@ use super::types::{
 };
 use crate::config::{WebDebugConfig, WebLimitsConfig};
 
+// WebSocket message capture is isolated from HTTP exchange storage.
+mod websocket;
+
 const BASE_RECORD_RESERVATION: usize = 1024;
 
 struct RingState {
@@ -66,6 +69,7 @@ pub(crate) struct WebTraceStore {
     records_capacity: usize,
     bytes_capacity: usize,
     max_carrier_body_bytes: usize,
+    frame_limits: WebLimitsConfig,
     used_bytes: Arc<AtomicUsize>,
     ring: Mutex<RingState>,
     next_record_seq: AtomicU64,
@@ -86,7 +90,8 @@ impl WebTraceStore {
             epoch: AtomicU64::new(1),
             records_capacity: limits.debug_records_capacity,
             bytes_capacity: limits.debug_bytes_global,
-            max_carrier_body_bytes: limits.max_body_bytes,
+            max_carrier_body_bytes: limits.max_body_bytes.max(limits.carrier_batch_bytes),
+            frame_limits: limits.clone(),
             used_bytes: Arc::new(AtomicUsize::new(0)),
             ring: Mutex::new(RingState {
                 records: VecDeque::with_capacity(limits.debug_records_capacity),
@@ -171,22 +176,14 @@ impl WebTraceStore {
             .user
             .as_ref()
             .map_or(0, String::len)
-            .checked_add(
-                identity
-                    .key_fingerprint
-                    .as_ref()
-                    .map_or(0, String::len),
-            );
-        let Some(reservation) = identity_bytes
-            .and_then(|bytes| BASE_RECORD_RESERVATION.checked_add(bytes))
+            .checked_add(identity.key_fingerprint.as_ref().map_or(0, String::len));
+        let Some(reservation) =
+            identity_bytes.and_then(|bytes| BASE_RECORD_RESERVATION.checked_add(bytes))
         else {
             self.record_truncation();
             return;
         };
-        if !policy.enabled
-            || !policy.capture_lifecycle
-            || !self.try_reserve_record(reservation)
-        {
+        if !policy.enabled || !policy.capture_lifecycle || !self.try_reserve_record(reservation) {
             return;
         }
         let record = TraceRecord {
diff --git a/src/web/trace/store/websocket.rs b/src/web/trace/store/websocket.rs
new file mode 100644
index 0000000..7c55f70
--- /dev/null
+++ b/src/web/trace/store/websocket.rs
@@ -0,0 +1,220 @@
+use std::net::IpAddr;
+use std::sync::atomic::Ordering;
+
+use crate::config::WebDebugBodyCapture;
+use crate::web::frame::{self, FrameType};
+
+use super::super::types::{
+    TraceBodySnapshot, TraceBodyState, TraceDirection, TraceFrame, TraceIdentity, TraceRecord,
+    TraceRecordKind, TraceWebSocketContext, TraceWebSocketRecord,
+};
+use super::{BASE_RECORD_RESERVATION, WebTraceStore, epoch_millis};
+
+impl WebTraceStore {
+    /// Builds connection metadata only while WebSocket debugging is enabled.
+    pub(crate) fn websocket_context<B, F>(
+        &self,
+        request: &hyper::Request<B>,
+        peer_ip: IpAddr,
+        effective_ip: IpAddr,
+        connection_id: u64,
+        lane_id: Option<u32>,
+        identity: F,
+    ) -> Option<TraceWebSocketContext>
+    where
+        F: FnOnce() -> TraceIdentity,
+    {
+        if !self.enabled.load(Ordering::Acquire) || !self.policy.load().enabled {
+            return None;
+        }
+        let user_agent = request
+            .headers()
+            .get(hyper::header::USER_AGENT)
+            .map(|value| super::super::sanitize::bounded_text(value.as_bytes(), 512));
+        Some(TraceWebSocketContext {
+            connection_id,
+            peer_ip,
+            effective_ip,
+            user_agent,
+            identity: identity(),
+            lane_id,
+        })
+    }
+
+    /// Records one policy-bounded WebSocket message without retaining credentials.
+    pub(crate) fn record_websocket_message(
+        &self,
+        context: &TraceWebSocketContext,
+        direction: TraceDirection,
+        message_type: &'static str,
+        payload: &[u8],
+        duration_us: u64,
+    ) {
+        if !self.enabled.load(Ordering::Acquire) {
+            return;
+        }
+        let epoch = self.epoch.load(Ordering::Acquire);
+        let policy = self.policy.load_full();
+        if !policy.enabled {
+            return;
+        }
+        let capture_limit = super::super::sanitize::capture_limit(
+            &policy,
+            super::super::types::TraceRoute::Websocket,
+            self.max_carrier_body_bytes,
+        )
+        .unwrap_or(0);
+        let capture_bytes = payload.len().min(capture_limit);
+        let frame_reservation = policy
+            .capture_frames
+            .then(|| {
+                payload
+                    .len()
+                    .div_ceil(frame::HEADER_BYTES)
+                    .clamp(1, self.frame_limits.max_frames_per_body)
+                    .saturating_mul(std::mem::size_of::<TraceFrame>())
+            })
+            .unwrap_or(0);
+        let identity_bytes = context
+            .identity
+            .user
+            .as_ref()
+            .map_or(0, String::len)
+            .saturating_add(
+                context
+                    .identity
+                    .key_fingerprint
+                    .as_ref()
+                    .map_or(0, String::len),
+            );
+        let reservation = BASE_RECORD_RESERVATION
+            .saturating_add(identity_bytes)
+            .saturating_add(context.user_agent.as_ref().map_or(0, String::len))
+            .saturating_add(capture_bytes)
+            .saturating_add(frame_reservation);
+        if !self.try_reserve_record(reservation) {
+            return;
+        }
+        let body = (policy.body_capture != WebDebugBodyCapture::Off).then(|| TraceBodySnapshot {
+            observed_bytes: payload.len() as u64,
+            captured: payload[..capture_bytes].to_vec(),
+            truncated: capture_limit != 0 && capture_bytes < payload.len(),
+            state: TraceBodyState::Complete,
+        });
+        let frames = if policy.capture_frames && message_type == "binary" {
+            websocket_frames(direction, payload, &self.frame_limits)
+        } else {
+            Vec::new()
+        };
+        let record = TraceRecord {
+            seq: self.next_record_seq(),
+            epoch_millis: epoch_millis(),
+            peer_ip: Some(context.peer_ip),
+            effective_ip: Some(context.effective_ip),
+            user_agent: context.user_agent.clone(),
+            identity: context.identity.clone(),
+            kind: TraceRecordKind::Websocket(TraceWebSocketRecord {
+                direction,
+                message_type,
+                payload_bytes: payload.len(),
+                body,
+                frames,
+                duration_us: policy.capture_timings.then_some(duration_us),
+                connection_id: context.connection_id,
+                lane_id: context.lane_id,
+            }),
+        };
+        if !self.try_commit(record, reservation, epoch) {
+            self.release(reservation);
+        }
+    }
+}
+
+fn websocket_frames(
+    direction: TraceDirection,
+    payload: &[u8],
+    limits: &crate::config::WebLimitsConfig,
+) -> Vec<TraceFrame> {
+    match frame::parse_all(payload, limits) {
+        Ok(frames) => frames
+            .into_iter()
+            .map(|value| TraceFrame {
+                direction,
+                frame_type: Some(super::super::sanitize::frame_type_name(value.frame_type)),
+                stream_id: Some(value.stream_id),
+                payload_len: Some(value.payload.len()),
+                window_delta: (value.frame_type == FrameType::Window)
+                    .then(|| frame::window_amount(value.payload).ok())
+                    .flatten(),
+                parse_error: None,
+            })
+            .collect(),
+        Err(error) => vec![TraceFrame {
+            direction,
+            frame_type: None,
+            stream_id: None,
+            payload_len: None,
+            window_delta: None,
+            parse_error: Some(super::super::sanitize::frame_error_name(error)),
+        }],
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::config::{WebDebugConfig, WebLimitsConfig};
+    use crate::web::frame::FrameType;
+
+    #[test]
+    fn websocket_message_capture_retains_bounded_identity_body_timing_and_frames() {
+        let mut policy = WebDebugConfig::default();
+        policy.enabled = true;
+        policy.capture_frames = true;
+        policy.capture_timings = true;
+        policy.body_capture = WebDebugBodyCapture::Full;
+        let mut limits = WebLimitsConfig::default();
+        limits.debug_records_capacity = 4;
+        limits.debug_bytes_global = 64 * 1024;
+        let store = WebTraceStore::new(policy, &limits);
+        let request = hyper::Request::builder()
+            .header(hyper::header::USER_AGENT, "trace-client")
+            .body(())
+            .unwrap();
+        let context = store
+            .websocket_context(
+                &request,
+                "127.0.0.1".parse().unwrap(),
+                "192.0.2.10".parse().unwrap(),
+                17,
+                Some(7),
+                || TraceIdentity {
+                    session_id: Some(42),
+                    user: Some("alice".to_string()),
+                    key_fingerprint: Some("0123456789abcdef".to_string()),
+                },
+            )
+            .unwrap();
+        let payload = crate::web::frame::encode(FrameType::Pong, 0, &[]);
+        store.record_websocket_message(&context, TraceDirection::Request, "binary", &payload, 123);
+
+        let records = store.snapshot_matching(|_| true);
+        assert_eq!(records.len(), 1);
+        assert_eq!(
+            records[0].record.user_agent.as_deref(),
+            Some("trace-client")
+        );
+        let TraceRecordKind::Websocket(message) = &records[0].record.kind else {
+            panic!("expected WebSocket trace");
+        };
+        assert_eq!(message.connection_id, 17);
+        assert_eq!(message.lane_id, Some(7));
+        assert_eq!(message.duration_us, Some(123));
+        assert_eq!(
+            message.body.as_ref().unwrap().captured.as_slice(),
+            payload.as_ref()
+        );
+        assert_eq!(message.frames.len(), 1);
+        assert_eq!(message.frames[0].frame_type, Some("PONG"));
+    }
+}
diff --git a/src/web/trace/types.rs b/src/web/trace/types.rs
index d26a094..d6fa36c 100644
--- a/src/web/trace/types.rs
+++ b/src/web/trace/types.rs
@@ -15,6 +15,8 @@ pub(crate) enum TraceRoute {
     Uplink,
     /// Carrier downlink exchange.
     Downlink,
+    /// WebSocket upgrade handshake.
+    Websocket,
 }
 
 impl TraceRoute {
@@ -27,6 +29,7 @@ impl TraceRoute {
             Self::Session => "session",
             Self::Uplink => "uplink",
             Self::Downlink => "downlink",
+            Self::Websocket => "websocket",
         }
     }
 }
@@ -180,6 +183,44 @@ pub(crate) struct TraceHttpRecord {
     pub(crate) timings: Option<TraceTimings>,
 }
 
+/// Stable non-secret metadata retained across one WebSocket connection.
+#[derive(Clone, Debug)]
+pub(crate) struct TraceWebSocketContext {
+    /// Process-unique connection identifier.
+    pub(crate) connection_id: u64,
+    /// Direct listener peer address.
+    pub(crate) peer_ip: IpAddr,
+    /// Trusted effective client address.
+    pub(crate) effective_ip: IpAddr,
+    /// Bounded user-agent copied only while debugging is enabled.
+    pub(crate) user_agent: Option<String>,
+    /// Session and profile identity without credentials.
+    pub(crate) identity: TraceIdentity,
+    /// Logical lane identifier for websocket-lanes.
+    pub(crate) lane_id: Option<u32>,
+}
+
+/// One bounded ordered WebSocket message observation.
+#[derive(Debug)]
+pub(crate) struct TraceWebSocketRecord {
+    /// Wire direction of this message.
+    pub(crate) direction: TraceDirection,
+    /// Closed RFC 6455 message category.
+    pub(crate) message_type: &'static str,
+    /// Total payload bytes observed.
+    pub(crate) payload_bytes: usize,
+    /// Policy-bounded message body observation.
+    pub(crate) body: Option<TraceBodySnapshot>,
+    /// Parsed carrier frames for binary messages.
+    pub(crate) frames: Vec<TraceFrame>,
+    /// Message processing or write duration when timing capture is enabled.
+    pub(crate) duration_us: Option<u64>,
+    /// Process-unique owning WebSocket connection.
+    pub(crate) connection_id: u64,
+    /// Logical lane identifier for websocket-lanes.
+    pub(crate) lane_id: Option<u32>,
+}
+
 /// Closed WEB lifecycle event category.
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub(crate) enum TraceLifecycleEvent {
@@ -257,6 +298,8 @@ pub(crate) struct TraceLifecycleRecord {
 pub(crate) enum TraceRecordKind {
     /// HTTP request-to-response exchange.
     Http(TraceHttpRecord),
+    /// One ordered WebSocket message.
+    Websocket(TraceWebSocketRecord),
     /// Session or stream lifecycle event.
     Lifecycle(TraceLifecycleRecord),
 }