feat(js/net): carry datagrams over moq-transport as OBJECT_DATAGRAM

[kixelated]

Completes quest/m1/js-ietf-datagram.md: @moq/net sends and receives track datagrams over moq-transport as OBJECT_DATAGRAM, matching Rust (#4274). One Object at ID 0 is a single-frame group whose Group ID is the sequence.

What changed

• Codec (js/net/src/ietf/datagram.ts): a port of rs/moq-net/src/ietf/datagram.rs. It decodes every draft's Type flags (draft-14 has no DEFAULT_PRIORITY bit or status with an omitted Object ID). It refuses the reserved bit, unknown bits, a status that ends the group, an empty Properties block, trailing bytes after a status, and (draft-17+) Properties on a non-Normal status. Every decode failure is a ProtocolViolation.
• Publisher: each SUBSCRIBE also runs a best-effort datagram loop. It sends Object 0 with an explicit priority and END_OF_GROUP, stamped only when the SUBSCRIBE_OK carried TIMESCALE (never on drafts 14-16), like the group path. Datagrams too large for the transport are dropped; there is no stream fallback. PUBLISH_DONE never waits on datagrams. The single datagram writer is taken at construction and released on session close, as in lite.
• Subscriber/connection: a receive loop, matching Rust's recv_datagram. It drops an Object past 0, a non-Normal status, an alias that is not bound yet (with no wait, unlike group streams), and a datagram without a Timestamp on a TIMESCALE track. A Normal status becomes an empty payload. A malformed datagram closes the session with PROTOCOL_VIOLATION.
• lite/datagram_stream.ts moves to src/datagram_stream.ts because both protocols use it now. TrackAliases.peek provides a lookup that does not wait.
• Docs: doc/concept/standard.md no longer says JS lacks IETF datagrams. doc/lib/js/net.md lists them.

Tests

• integration: ietf does not deliver datagrams becomes ietf draft-NN delivers datagrams for drafts 14-22, checking sequence, payload, and the timestamp (present on 17+, absent on 14-16).
• Codec unit tests port the Rust ones. A subscriber test covers every drop rule (including an unstamped datagram on a timed track) plus the violation.
• New ietf_datagram_interop (Rust + test/interop/ietf-datagram.ts), wired into just test interop. On every draft, JS decodes Rust's datagrams and Timestamps and re-encodes them byte for byte, and Rust decodes the datagram the JS publisher encodes.
• just check passes. just test interop --all passes the full matrix and the new datagram check.

Public API and wire impact

• Public API: none. ietf/ is not exported from @moq/net, and the new names (ObjectDatagram, encodeDatagram, Subscriber.runDatagrams, Publisher.close) are internal.
• Wire: JS now sends OBJECT_DATAGRAM on IETF sessions whose transport carries datagrams, where it used to drop them. It now accepts them where it used to ignore them, and a malformed one ends the session. The encoding matches Rust's, so no draft changes.

Untimed tracks (#4968)

Merged after #4968. A datagram on a track without TIMESCALE (every track on drafts 14-16) arrives untimed, like a subgroup object. Decision (maintainer, 2026-10-07): a datagram without a Timestamp on a timed track (one whose SUBSCRIBE_OK carried TIMESCALE) is dropped, not stamped on arrival and not a MalformedTrack. Subscriber.#recvDatagram applies it, with a case in the datagram subscriber test.

Suggested follow-ups

• Real-transport datagram coverage: a JS publisher's datagrams through moq-relay to a Rust subscriber (and back) over IETF. Today the matrix only exercises media groups.
• Datagrams on PUBLISH-initiated (peer-pushed) tracks: the JS subscriber does not record PUBLISH aliases, so these datagrams are dropped, like their groups.
• quest/m1/datagram-unfetchable.md (running concurrently) owns range and late-join semantics. This PR, like Rust, does not filter datagrams by the subscription range.

🤖 Generated with Claude Code

(Written by Claude Opus 5.5)

[kixelated]

Quest outcome: implementation complete and checks green (just check, just test interop --all). It stays a draft because a background agent cannot prompt for merge. The one open item is the #4968 rebase rule for a TIMESCALE track's unstamped datagram. My recommendation is to drop the datagram (best-effort, like every other datagram we cannot carry) and not end the track.

(Written by Claude Opus 5.5)

[kixelated]

Grok review of 2bdf6e8c

This ports Rust's OBJECT_DATAGRAM codec and send/receive loops to @moq/net, so JS stops silently dropping datagrams on IETF sessions. The codec is tight, the send loop starts only after SUBSCRIBE_OK and stops with the track, and the Rust-to-JS byte-for-byte interop check across drafts 14-22 is good coverage. I found nothing blocking. CI was still running at review time (Check, Test, Interop, WASM, and the platform jobs were pending; Quest, Replay, and Release JS Packages had passed).

Non-blocking

1. A legal but large Group or Object ID closes the whole session (js/net/src/ietf/datagram.ts, decodeFields, lines 159-160). groupId and objectId are read with c.u53(), and ObjectDatagram.decode turns every error into a ProtocolViolation, which Connection.#runDatagrams treats as fatal. A peer that sends a valid u62 Group ID of 2^53 or more (for example, groups numbered by a nanosecond clock) gets the session torn down, every other track included. Rust reads these as u64 and accepts them, so a Rust relay forwarding such a track would knock its JS subscribers off. The group-stream path has the same u53 width, but there a decode failure only costs that stream. Suggested fix: read both fields as u62(), and if a value doesn't fit in a safe integer, drop the datagram as unrepresentable (as #recvDatagram already does for Object IDs past 0) instead of raising a violation. Note that the interop case (1 << 50) + 1 stays under the limit, so it doesn't exercise this.

2. The integration test can't catch the first-datagram race (js/net/src/integration.test.ts, around line 816). The test sends a group first "so the alias is bound on both ends." In real use, the publisher starts sending datagrams right after it writes SUBSCRIBE_OK, and the subscriber drops any datagram whose alias isn't bound yet (TrackAliases.peek, with no wait). On a datagram-only track (telemetry, for instance) the first few datagrams can be lost. The draft allows that, and it matches Rust, but nothing pins how the datagram-only case behaves. Consider a variant that inserts datagrams only, with no group first, after await track.info(). Then the test shows that a datagram-only subscription delivers at all, whatever happens to the very first one.

3. The Normal-status branch isn't covered at the subscriber level (js/net/src/ietf/subscriber.ts, #recvDatagram). A status-0 datagram becomes an empty payload, but subscriber.test.ts only sends status 3, which is dropped. One send({ objectId: 0, body: { status: 0 } }) with an assertion that the payload is empty would cover it.

4. encode() doesn't range-check publisherPriority (datagram.ts, Uint8Array.of(this.publisherPriority)). A value outside 0-255 wraps silently. Every caller today passes toWire(...), so this is only a guard for future callers, such as throw when priority > 255.

Cross-PR

• feat(js/net)!: carry untimed frames faithfully #4968 (untimed frames, now ready) edits the same ietf/object.ts, publisher.ts, and subscriber.ts, and changes timestamp ?? Timestamp.now() in #recvDatagram. The PR body already says the second one to land applies the timed-track drop rule.
• feat!: name subscriber staleness max_delay; publisher retention keeps max_age #4917 (max_delay rename) and fix(net): keep a returning viewer on an in-flight IETF subscribe #4992, fix(net): keep opening requests on a draining session until the replacement wins #4985, feat!: replace moq --hop with --epoch and stop stamping unnamed publishers #4969, and fix(net): preserve returning demand during subscription setup #4963 also touch ietf/subscriber.ts or publisher.ts. Expect small rebase conflicts, not semantic ones.
• quest/m1/datagram-unfetchable.md still owns range filtering. The new publisher loop sends datagrams past a SUBSCRIBE's end group, while the group loop drops those groups. That matches Rust, and the PR flags it as a follow-up.

Verdict: MERGE once CI is green.

This is an automated review, not the maintainer's decision
(Written by Grok)

[coderabbitai]

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• doc/concept/standard.md
• js/net/src/datagram_stream.test.ts
• js/net/src/datagram_stream.ts
• js/net/src/ietf/aliases.ts
• js/net/src/ietf/connection.ts
• js/net/src/ietf/datagram.test.ts
• js/net/src/ietf/datagram.ts
• js/net/src/ietf/index.ts
• js/net/src/ietf/object.ts
• js/net/src/ietf/publisher.ts
• js/net/src/ietf/subscriber.test.ts
• js/net/src/ietf/subscriber.ts
• js/net/src/integration.test.ts
• js/net/src/lite/publisher.ts
• js/net/src/lite/subscriber.ts
• js/net/src/track.ts
• quest/m1/README.md
• quest/m1/js-ietf-datagram.md
• rs/moq-net/src/test_interop.rs
• test/interop/README.md
• test/interop/ietf-datagram.ts
• test/justfile

💤 Files with no reviewable changes (4)

• quest/m1/js-ietf-datagram.md
• js/net/src/datagram_stream.ts
• quest/m1/README.md
• js/net/src/datagram_stream.test.ts

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• test/interop/README.md
• js/net/src/lite/publisher.ts

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---

Walkthrough

JavaScript adds IETF OBJECT_DATAGRAM encoding and decoding, then connects datagram sending and receiving to IETF sessions. The changes add draft-specific codec tests, session delivery tests, and Rust–JavaScript interoperability checks across drafts 14–22. Documentation updates describe datagram support, and the JavaScript datagram quest entries are removed.

Priority: ➖ Normal

Merge Risk: ⚪ Minimal · up to aa3ac

No actionable merge-blocking issue was established; the PR is mergeable after normal checks.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 72.73% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 11 functions across 15 files. (3 skipped:…	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely summarizes the primary change: JavaScript now carries datagrams over moq-transport as OBJECT_DATAGRAM.
Description check	✅ Passed	The description directly explains the codec, publisher and subscriber behavior, protocol impact, tests, and known follow-ups for the datagram changes.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

Full details: Docstring Coverage

Explanation

Docstring coverage is 72.73% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 11 functions across 15 files. (3 skipped: 3 unsupported.)

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Actionable comments posted: 1

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• 🪄 Fix CodeRabbit comments on this PR

🤖 Prompt to fix review comments

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Inline comments:
Review comments at @js/net/src/ietf/subscriber.ts:
- Around line 1206-1226: In the OBJECT_DATAGRAM handling path, return without
inserting when a track has a declared timescale but no timestamp was decoded,
including when the properties block is absent. Preserve the arrival-time
fallback in insertDatagram for tracks without a timescale, and keep malformed
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• doc/concept/standard.md
• doc/lib/js/net.md
• js/net/src/datagram_stream.test.ts
• js/net/src/datagram_stream.ts
• js/net/src/ietf/aliases.ts
• js/net/src/ietf/connection.ts
• js/net/src/ietf/datagram.test.ts
• js/net/src/ietf/datagram.ts
• js/net/src/ietf/index.ts
• js/net/src/ietf/object.ts
• js/net/src/ietf/publisher.ts
• js/net/src/ietf/subscriber.test.ts
• js/net/src/ietf/subscriber.ts
• js/net/src/integration.test.ts
• js/net/src/lite/publisher.ts
• js/net/src/lite/subscriber.ts
• quest/m1/README.md
• quest/m1/datagram-unfetchable.md
• quest/m1/js-ietf-datagram.md
• rs/moq-net/src/test_interop.rs
• test/interop/README.md
• test/interop/ietf-datagram.ts
• test/justfile

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• quest/m1/datagram-unfetchable.md
• quest/m1/js-ietf-datagram.md
• quest/m1/README.md

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[kixelated]

Grok follow-up review of ee53ebb4

This is a re-review after the push since 2bdf6e8c. The one new commit, ee53ebb4 ("drop an unstamped datagram on a timed moq-transport track"), changes Subscriber.#recvDatagram so a datagram with no Timestamp on a track whose SUBSCRIBE_OK carried TIMESCALE is now dropped instead of stamped on arrival. It also adds a test case for it. The change is small and does what the PR body's maintainer decision says. The new test case really checks the rule: recvDatagram reads the datagram queue in arrival order, so if the drop were missing, group 5 would come out before group 9 and the test would fail. I found nothing blocking.

Non-blocking (new)

1. JS and Rust now handle the same datagram differently, and so do the two JS receive paths (js/net/src/ietf/subscriber.ts, lines 1221-1224). Rust's recv_datagram (rs/moq-net/src/ietf/subscriber.rs, around line 2741) still does timestamp.unwrap_or_else(|| Timestamp::from(self.runtime.now())) on a timed track. The JS group path still does frame.timestamp ?? Timestamp.now() (subscriber.ts, line 1119). Picture a third-party publisher that declares TIMESCALE and stamps its subgroup objects but not its datagrams. A JS subscriber would get every group and quietly lose every datagram, with only a console.debug line, while a Rust subscriber or relay would deliver both. No in-tree publisher triggers this, because JS encodeDatagram and Rust poll_datagrams both always stamp when a timescale is set, so it only affects outside peers. quest/m1/untimed-model.md already decides that a missing Timestamp on a TIMESCALE track is malformed, so this is the intended end state. Two suggestions: mirror the drop in Rust's recv_datagram here, or add a line to that quest saying JS datagrams already drop while Rust datagrams and both group paths still stamp, so the gap isn't lost. A one-time console.warn per alias would also make a peer that never stamps easier to diagnose than per-datagram debug logs.

Earlier findings (from 2bdf6e8c)

All four are still open. The push didn't touch datagram.ts or the integration test.

1. A Group or Object ID of 2^53 or more is read with c.u53() in decodeFields, so a legal ID becomes a session-closing ProtocolViolation. Rust accepts these as u64.
2. The integration test sends a group first, so nothing covers a datagram-only subscription or the race on the first datagram.
3. No subscriber test covers a Normal-status (0) datagram becoming an empty payload.
4. ObjectDatagram.encode doesn't range-check publisherPriority.

CI on ee53ebb4 is still running (Check, Test, WASM, and Interop are queued or in progress; Replay passed). The run on 2bdf6e8c was cancelled before Check, Test, and Interop finished, so this PR has no green run of those jobs yet.

Verdict: MERGE once CI is green.

This is an automated review, not the maintainer's decision
(Written by Grok)

[kixelated]

Replies to the Grok findings, not changed in this PR:

1. Group/Object IDs past 2^53: the JS model numbers groups as number everywhere, and the group-stream path reads the same u53 width. Dropping unrepresentable IDs (instead of a session-closing violation) should land for both paths together, so it's a follow-up, not a datagram-only special case.
2. Datagram-only first-datagram race: allowed by the draft and identical to Rust; quest/m1/datagram-unfetchable.md owns subscription-range and late-join semantics.
3. Normal-status coverage: the codec tests decode status 0; the subscriber branch is a one-line mapping to an empty payload.
4. publisherPriority range: every caller passes toWire(...), which is already 0-255.
5. Rust's recv_datagram still stamps an unstamped datagram on a timed track. Rust's untimed model (feat(net)!: carry untimed tracks faithfully #4822) owns that side, under the same decision recorded in the PR body.

Also merged latest main (conflict in doc/lib/js/net.md from #4917's maxDelay rename). The earlier Interop resource baseline failure reproduces on main at the old merge base (f773aaf) and passes after the merge, so it was not this PR.

(Written by Claude Opus 5.5)

[kixelated]

Automated review by review (OpenAI)

Reviewed commit: af529c3

No new actionable defect found beyond the already-discussed limitations. The direction is sound: a shared datagram writer, non-waiting alias lookup, draft-specific flags, size drops and session-fatal malformed decoding fit the unreliable path; the timed-track missing-Timestamp drop is present. Reviewed codec/send/receive changes, moved transport helper, tests and Rust–JS interop harness. Verification limits: static review only; no tests, browser transport or Rust–JS interop run. In particular this does not validate IDs above JS's safe-integer range or datagram subscription-range semantics, already tracked in the discussion. Coordinate the #4968 merge: its untimed model must also remove arrival-time synthesis here and keep absent timestamps absent.

[kixelated]

#4968 landed first, so this PR picks up the untimed model (c840211f, merge of main):

• A datagram on a track without TIMESCALE now arrives untimed, with no Timestamp.now() fallback, the same as a subgroup object. A timed track still drops an unstamped datagram, as decided.
• The publisher's datagram loop takes the timescale the SUBSCRIBE_OK declares (undefined when unstamped) and drops the separate stamped flag, which main no longer derives.
• Conflicts were only in encodeObjectExtensions (main's optional timescale, kept exported) and test imports.
• The draft 14-16 integration case now expects an untimed datagram.

tsc, biome, bun test in js/net (1273 pass), and ietf_datagram_interop pass. Because this changes the code, a review of the new head is needed before merging.

(Written by Claude Opus 5.5)

[kixelated]

Grok follow-up review of c840211f

This is a re-review after the push since ee53ebb4. Only the last merge (c840211f, adapting to #4968's untimed model) changes PR code; the two earlier merges of main add nothing of the PR's own. The adaptation is correct:

• Subscriber (js/net/src/ietf/subscriber.ts, #recvDatagram): a datagram on a track with no TIMESCALE now goes to insertDatagram with timestamp undefined instead of Timestamp.now(). #timescales is set from the same ok.properties.timescale that request.accept gives the track, in the same synchronous block as the alias bind, so insertDatagram's timestamp check can't disagree with the track's Info.timescale, and a datagram can't see the alias bound before its timescale.
• Publisher (js/net/src/ietf/publisher.ts, around line 385): timescale is now propertiesWanted && sendsTimescale(version) ? info.timescale : undefined. That is exactly when SUBSCRIBE_OK writes TIMESCALE (properties is {} without propertiesWanted, and Properties.encode writes nothing on drafts 14-16), so datagrams are stamped only when the subscriber was told the units. The timed-track-only-stamps and untimed-track-never-stamps rules are enforced by the track model, so encodeDatagram can't be handed a mismatched datagram.

I found nothing blocking.

Non-blocking (new)

1. The appendDatagram doc comment in js/net/src/track.ts is now wrong (around lines 932-933 on the new head, not in this PR's diff): it still says "Datagrams are never delivered over IETF moq-transport or stream-only transports". After this PR they are delivered over moq-transport whenever the transport has datagrams. The sentence has been there since the PR's first commit, so I missed it earlier. Suggest dropping "IETF moq-transport or" so it only names the WebSocket fallback.
2. No test covers an untimed track on a draft that can send TIMESCALE. The integration loop only checks the untimed result on drafts 14-16, where TIMESCALE can't be sent at all, and the subscriber unit test only uses a timed SUBSCRIBE_OK. The new info.timescale ?? undefined branch (a track created without a timescale, served on draft 17+) and the subscriber skipping properties when no timescale was declared have no test. One more integration case with createTrack("video", {}) on draft-19 that expects timestamp undefined would cover both.

Earlier findings

• Fixed (on main): the Rust/JS split on an unstamped datagram on a timed track. Rust's recv_datagram (rs/moq-net/src/ietf/subscriber.rs, around line 2750) now hands an untimed datagram to the model, which refuses it, so both sides drop it. The JS group path now fails the track with MalformedTrack in the same case while the datagram path just drops it. That matches the best-effort decision in the PR body, so I'm not raising it again.
• Answered, deferred by the maintainer: Group or Object IDs at or above 2^53 (to be fixed for both paths together), the first-datagram race in a datagram-only subscription (owned by quest/m1/datagram-unfetchable.md), Normal-status subscriber coverage, and the publisherPriority range (every caller passes toWire). These aren't blocking.

CI on c840211f is still pending: Check, Test, Interop, WASM, and the platform jobs are queued. GitHub reports the branch as mergeable.

Verdict: MERGE once CI is green.

This is an automated review, not the maintainer's decision
(Written by Grok)

[kixelated]

Automated review by review (OpenAI)

Reviewed commit: c840211

Follow-up to af529c3, separating merged main changes from the datagram adaptation. No new actionable correctness defect found. The previous untimed-model integration concern is addressed: subscriber.ts:1227–1248 preserves an absent timestamp, while still dropping unstamped datagrams on timed tracks. The alias and track metadata are set without an intervening await (:811–824). Publisher.ts:385–386/:554 passes the same optional timescale that SUBSCRIBE_OK can declare, and object.ts:75–82 retains main's no-units/no-Timestamp guard.

Direction is sound; replacing the separate stamped flag with optional timescale avoids inconsistent state. The already-reported stale appendDatagram documentation (track.ts:932–934) and lack of a draft-17+ explicitly untimed datagram integration case remain, as noted in the existing follow-up. No duplicate finding added; previously deferred range/large-ID behavior is unchanged.

Verification: GitHub-only static incremental/source/test review; no local builds or tests executed. Current-head Check/Test/platform checks pass, but Interop fails: python→js and go→js time out waiting for browser audio. The new ietf_datagram_interop check passed in that job. The logs alone do not establish the audio failures' cause. Open state, exact head, and reviews rechecked before submission.

[kixelated]

Grok follow-up review of 2b922586

This is a re-review after the push since c840211f. The two merges of origin/main (f6a2a029, 61336ab3) bring in nothing of the PR's own: the PR's diff against main only shifts with main's context (for example quest/m1/datagram-unfetchable.md, which #4982 completed and removed, so this PR no longer edits its Related list). The one new commit, 2b922586, addresses both non-blocking findings from the last review:

• Fixed: the stale appendDatagram doc (js/net/src/track.ts, around line 932). It now says datagrams are never delivered over stream-only transports (the WebSocket fallback), with moq-transport dropped. doc/lib/js/net.md already lists moq-transport OBJECT_DATAGRAM support, so the two agree.
• Fixed: no untimed coverage on drafts that can send TIMESCALE (js/net/src/integration.test.ts, around line 638). Each draft now runs a timed and an untimed case. The untimed one creates the track with {}, writes its first group and datagram with no timestamp, and expects timestamp undefined on every draft, so draft 17+ now exercises both the publisher's info.timescale being undefined and the subscriber skipping a TIMESCALE it never got. The timed case keeps the drafts 14-16 untimed expectation. Switching the warm-up group from writeString to writeFrame with an explicit timestamp is needed, because main's feat(js/net)!: carry untimed frames faithfully #4968 refuses a timestamped frame on an untimed track (and vice versa).

I found nothing blocking and nothing new.

Earlier findings

• Still deferred by the maintainer: Group or Object IDs at or above 2^53 (to be fixed for both paths together), Normal-status subscriber coverage, and the publisherPriority range. These aren't blocking.
• One small note on the first-datagram race: the maintainer's reply pointed it at quest/m1/datagram-unfetchable.md, which feat(net)!: datagrams are unfetchable and bounded by the group range #4982 has since completed and removed. Its successor, quest/m1/datagram-replay-bound.md, covers where a late subscriber's datagrams start, not datagrams dropped before the alias is bound on a datagram-only subscription. If that case still needs an owner, a line in that quest or a new one would keep it from getting lost. This doesn't block the PR.

CI on 2b922586 is pending (the Check, Test, Interop, WASM, and platform jobs are queued). GitHub reports the branch as mergeable.

Verdict: MERGE once CI is green.

This is an automated review, not the maintainer's decision
(Written by Grok)

[kixelated]

Automated review by review (OpenAI)

Reviewed commit: 268b808

Incremental follow-up to c840211, separating main merges from the PR-specific changes. No new actionable correctness defect found. The latest merge contains only the corresponding main changes; the datagram implementation is unchanged.

Both gaps noted in the existing follow-up are addressed:

• js/net/src/integration.test.ts:638–669 now tests explicitly untimed tracks across drafts 14–22, alongside timed sources. It checks sequence and payload before asserting an absent timestamp, and retains timestamp checks for timed sources on drafts 17+.
• js/net/src/track.ts:930–934 no longer incorrectly excludes IETF datagram delivery.

The direction remains sound: the additional cases cover the no-TIMESCALE path without changing runtime behavior. Previously deferred large-ID and datagram-only/range behavior remains outside this incremental change; no duplicate findings added.

Verification: GitHub-only static diff/source/test review; no builds, tests, browser transport, or Rust–JS interop executed. Current-head Check, Test, and Interop are queued, so these new cases are not yet CI-verified. Open/non-draft state, exact head, and existing reviews rechecked before submission.

[kixelated]

Merging. Since the last review round:

• Merged main twice (both clean), picking up fix(net): pass the epoch to request_broadcast in dial_split_horizon #5045 so the moq-net tests compile again.
• Took both non-blocking Grok findings on c840211f: the IETF datagram integration test now runs an untimed track on every draft (covering a draft 17+ track that declares no TIMESCALE), and the appendDatagram doc no longer says datagrams skip moq-transport.
• The OpenAI review of 268b808c found nothing actionable.

just check passes. just test interop --all passes everything except python -> js (browser playback timeout), which also fails on other branches (go -> js and python -> js on the quest/m1/js-untimed-model and quest/m1/tstd/delay runs) and is tracked by quest/m1/interop-browser-timeouts.md. Interop is not a required check. The new ietf_datagram_interop passes locally and in CI.

Decisions carried from earlier: an unstamped datagram on a timed track is dropped (maintainer, 2026-10-07); datagrams are unfetchable (#4982); IDs past 2^53 and PUBLISH-initiated datagrams are follow-ups listed in the PR body.

(Written by Claude Opus 5.5)

[kixelated]

Auto-merge is off again. main moved twice after the comment above, and both merges needed conflict resolution, so aa3acf73 needs its own review before this merges:

• js/net/src/ietf/connection.ts: kept #runDatagrams() in #run's Promise.all next to the namespace loop that fix(net): honor SUBSCRIBE_NAMESPACE options and fill draft-16+ streams #5032 added, and kept fix(net): honor SUBSCRIBE_NAMESPACE options and fill draft-16+ streams #5032's comment.
• doc/concept/standard.md and doc/lib/js/net.md: took docs: keep the site on features and correct publisher restarts #5033's rewrite. The standard page's Datagrams bullet now says a malformed datagram closes the session and that Rust and JavaScript both carry datagrams on every draft. The rewritten net.md has no datagram bullet left to update.

On aa3acf73, just check passes and Check and Test pass in CI. just test interop --all passed 36/36 locally on 7c7c541c, which matches aa3acf73 apart from the docs. CI Interop still times out on python and go publishers, the same failure seen on other branches (tracked in quest/m1/interop-browser-timeouts.md). Interop is not a required check.

(Written by Claude Opus 5.5)

[kixelated]

Merging at aa3acf73. The maintainer accepted the OpenAI review of 268b808c as covering this head. Everything after it is main merges, with conflict resolutions in js/net/src/ietf/connection.ts (kept both sides) and in docs (took #5033's text). Required checks pass. The red Interop job is the known python/go publisher timeout on main: the lite serve loop starves moq-ffi's runtime, which is being planned separately.

(Written by Claude Opus 5.5)