fix(api): tolerate concurrent DNS record creation (fixes stuck deployments) - #45
fix(api): tolerate concurrent DNS record creation (fixes stuck deployments)#45defang-sam[bot] wants to merge 5 commits into
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Triaged the failing 1. 2. 3. 4. Also flagging: the PR body itself already marks Staging Verification as not performed and explicitly defers the merge decision to a human — so items 2–4 aside, this PR isn't self-mergeable regardless of CI state. I only edited the PR body (Preflight section) — no code changes, no merge action taken. |
A deployment stalled with no app-route DNS record and no TLS certificate. The
control plane had logged exactly one error in the whole window: a 500 from
GET /api/nodes/:id/deploy-release, thrown by upsertAppRouteDNSRecord out of a
Promise.all, with Cloudflare's "An identical record already exists."
That endpoint upserts every app-route DNS record before returning the node's
release payload, so the throw meant the node never received its release and the
deployment stalled upstream of anything cert-related. The missing certificate
was three layers downstream of the actual failure.
upsertAppRouteDNSRecord is a check-then-act with an await in the gap. Its only
production call site fans it out over every route via Promise.all, and
overlapping release fetches run the whole handler concurrently. Two callers both
observe "no record", both POST, and Cloudflare rejects the loser with 81058.
Evidence this is a race, not a stale record:
- the lookup is an exact ?type=A&name= match, so "not found, then rejected as
duplicate" can only mean the record appeared between the two calls;
- 81058 means same name AND type AND content (a cross-type collision returns
81053), so identical content = same node IP = two identical concurrent POSTs;
- deployment_release_events shows the handler running concurrently: two
fetch_started 1s apart and seq=4 written twice by two invocations;
- deleteAppRouteDNSRecord was already documented as tolerant of "a record
already removed by a concurrent caller" — delete had been hardened for
concurrency, create never was.
Fix: on the create path, treat the duplicate-record codes as a lost race —
re-resolve once and update in place. Scoped to 81057/81058 (81053 is a genuine
misconfiguration retrying cannot fix and still throws), to the create path only
(!existing), and bounded by DNS_UPSERT_RACE_MAX_RETRIES.
Also fixes the same class in createNodeBackendDNSRecord, in the same file, whose
failure mode was worse: a blind POST with no lookup at all. Two paths create that
record (services/nodes.ts provisioning and the node-lifecycle heartbeat
backfill); on conflict the caller stamps nodes.error_message and leaves
backend_dns_record_id NULL, so every later heartbeat retried the same losing POST
forever and node deletion — which deletes by that id — orphaned the real record.
It now resolves the winner so the id is persisted, converging the IP first since
81057 does not guarantee matching content.
readCloudflareErrorDetail reads {code, message} in one pass because a Response
body can only be consumed once; readCloudflareError delegates to it so the five
other call sites are unchanged. `code` is parsed as unknown and narrowed with
typeof at use — valibot's optional() only bypasses a missing key, so
v.optional(v.number()) would fail the whole entry on `code: null` and silently
replace Cloudflare's real message with a generic fallback for those five callers.
Process fix: .claude/rules/68-external-api-check-then-act.md. Its requirement 6
(check sibling operations in the same module) is what surfaced the
createNodeBackendDNSRecord instance.
Tests (dns-app-routes 14 -> 23, deploy-release-callback 31 -> 32) cover both
tolerated codes, the update-path guard, 81053 and auth controls, the null and
stringified code regressions, the single-retry bound, a same-hostname race
against a shared fake CF store, the Promise.all fan-out, five sibling tests, and
a route-level vertical slice. Each guard verified discriminating once and
reverted; notably, on pre-fix dns.ts the new route test fails while the other 31
route tests all pass — the existing suite could not observe the production 500.
Co-Authored-By: Claude <noreply@anthropic.com>
… pulls
Two further defects in the same incident: the cause of the DNS race above, and
the failure that was killing deployments outright.
1. Duplicate apply spawns
health.go spawned a new runDetachedDeploymentApply goroutine on every heartbeat
for every pending release, with no in-flight check. observed.AppliedSeq only
advances after a fully successful apply, so any release slower than one heartbeat
interval accumulated another concurrent apply per tick — each re-running the
whole control-plane fetch: re-decrypting secrets, re-minting a registry
credential, regenerating presigned artifact URLs, re-signing the payload, and
racing on app-route DNS creation.
Live evidence, env pr18-preview-3, one node, 13:53-15:19:
16x deployment.apply.fetch_started
8x deployment.apply.started
8x deployment.apply.compose_up_started
0x compose_up_completed
An exact 2:1 fetch/apply ratio. The duplicate's Apply() is rejected by the
engine's applyMu.TryLock(), which is why applies are half the fetches — but the
fetch has already run, and the fetch is what upserts DNS. 16 chances to lose the
race on one environment in 85 minutes.
claimJob(jobID) is an atomic claim over a shared in-flight set, applied to the
apply path and the route-config path, which had the same defect. Released via
defer, idempotent, and safe on a nil map so existing test fixtures still work.
2. Compose SIGKILLed mid-pull by the apply idle watchdog
The apply is bounded by a 15-minute IDLE timer reset only by ApplyProgressEvents
— the same events that become deployment_release_events rows. `docker compose up`
emits exactly one (compose_up_started) and then nothing until it returns, so a
legitimately slow image pull was indistinguishable from a hung apply. That is the
8-starts/0-completions column above, cycling every ~14 minutes, and it is what
produced `compose up: ... signal: killed (stderr: db Pulling ...)`.
Compose streams pull/extract progress to stderr, so that output is now the
liveness signal: runCompose wraps stderr in a livenessWriter that pokes the
watchdog per write without persisting an event, mirroring newIdleProgressReader
which already does exactly this for artifact downloads in the same package.
The buffer retains the TAIL, not the head. Compose prints megabytes of progress
and then the actual failure (`manifest unknown`, `no such image`, `no space left
on device`) on its last lines, so head-retention would discard precisely the
diagnostic the buffer exists to preserve. Compaction is amortized — the buffer
may reach 2x the cap before trimming — so a multi-megabyte pull costs O(total)
copying rather than O(total x limit).
3. The diagnostic that hid it
health.go overwrote the accurate "deployment apply stalled: no progress for
15m0s" with the child's `signal: killed`, which is a consequence of our own
cancel. The stall is now primary with the child result as context, so a
self-inflicted timeout is no longer indistinguishable from an OOM kill.
Process fix: .claude/rules/53 gains requirement 5c — the mirror image of its
existing liveness-as-idleness trap. There a liveness column answered an idleness
question; here a progress feed could not observe the work it guarded. Same
family, so it extends rule 53 rather than becoming a new file.
Tests, all under -race: liveness fires from real child output with the right
env/seq; silent-command and out-of-apply controls emit nothing; stderr survives
wrapping; the signal continues past the retention cap; tail retention asserted on
content both as a unit and end-to-end through a child emitting ~200 KiB before
failing; setActiveApplySeq restores on nest; concurrent seq access is race-free.
Dedup: duplicate skipped, different seq allowed, claim released on completion,
route path guarded, exclusive under 64 goroutines, idempotent release, nil map.
Each guard verified discriminating once and reverted: disabling the dedup guard
fails exactly the duplicate test with both controls green; a plain stderr buffer
fails exactly the liveness test; head-retention fails exactly the two tail tests.
vm-agent: build, vet, gofmt clean on all touched files; 23/23 packages pass;
deploy and server pass -race.
Co-Authored-By: Claude <noreply@anthropic.com>
Full incident record: the three defects, the live production evidence (2:1 fetch/apply ratio, 8 compose starts with zero completions), the discriminating- mutation table for every guard, the two bug classes and their process fixes, and the limitations left standing — the unexplained 1-second spacing of the original duplicate fetches, and the deployment_volumes.status staleness filed separately. The log excerpt is formatted one field per line: with `source=api` adjacent to the node ULID, gitleaks' generic-api-key rule matched the high-entropy identifier. It is a public node id that already appears in URLs and logs, not a credential, so the right resolution is to not trip the scanner rather than to self-approve a reviewed-baseline entry (which requires a security owner and an expiry). Co-Authored-By: Claude <noreply@anthropic.com>
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Follow-up triage on the new
No code or PR-body changes made this round — the actionable blockers ( |
…napshot attachEnvironmentVolumes wrote `attached.status` straight from the provider's attachVolume response. Hetzner commonly still reports `creating` at that instant, and nothing ever re-polls the row — the only other writer is the detach path. So an attached, mounted, fully working volume read `creating` forever. Observed in production on volume 01M1RWP6VA… (pgdata) while its own release events showed volume_mount_completed and volume_mounts_verified — the mount demonstrably worked. Nothing reads the column (every `.status` branch in the consumers is on node.status or environment.status, and the heartbeat gate deploymentVolumesReadyForNode keys on attached_server_id), so this is not a functional bug. It is worse in a specific way: it is the single most obvious "here is your stuck deployment" signal in the table, and it is false. It misdirected this investigation, and would misdirect the next one. Now persists the settled SAM-side fact — the attach call returned and we hold a server id, so `attached` is true and stable. No migration and no constraint widening: the column is plain TEXT with no CHECK (0069_deployment_volumes.sql:14) and `attached` is already in the provider VolumeStatus union. The `failed` semantics on the creation path are untouched. Rule 57 at the storage layer: a remote-owned value written once and never reconciled. Polling was rejected as disproportionate — the fact SAM needs is knowable locally the moment attach returns. Test asserts the settled status survives a provider still reporting `creating`; verified discriminating (restoring the pass-through fails exactly it plus the existing attach assertion). API unit suite 8053/8054, 0 collection errors. Co-Authored-By: Claude <noreply@anthropic.com>
Both were reported as "pre-existing failures" in earlier CI runs on this branch. They are not flakes and were never going to self-resolve — each hardcodes a historical date and seeds fixture data relative to it, while the PRODUCTION code it exercises checks that data against REAL wall-clock time with no injectable clock. Both were guaranteed to start failing on a specific calendar date regardless of any code change, and did. 1. project-data-snapshot-recovery-wake.test.ts NOW = 2026-08-26T21:10:00Z; seedSnapshot() sets expires_at = NOW + 7 days = 2026-09-02. wakeSessionForSnapshotRecovery -> hasAuthorizedRestorableSnapshot- WakeClaim calls the latter WITHOUT passing `now`, so it defaults to `new Date()` -- real time. From 2026-09-02 onward `expires_at > now` is false, the claim row never matches, and the test's `.resolves.toBe(true)` fails. Fix: freeze the clock (vi.useFakeTimers + setSystemTime(NOW) in beforeEach, vi.useRealTimers in afterEach) so the production default resolves to the fixture's NOW instead of real time. All 7 tests in the file still pass. 2. project-data-tool-payload-archive.test.ts > retrieves archived tool payloads through the MCP tool The file's FIXED_NOW (2026-08-26) is used correctly everywhere else -- threaded explicitly through runArchiveCleanup's `now`/`nowMs` for the archival business logic. But this one test also stamped an MCP token's createdAt with that same FIXED_NOW. validateMcpToken has NO injectable clock (`const now = Date.now()`, hardcoded by design -- it's an auth boundary) and rejects tokens older than DEFAULT_MCP_TOKEN_MAX_LIFETIME_SECONDS (24h). Once real time passed 2026-08-27 the token looked ~10 days old and every call 401'd. Fix: stamp the token with the real current time (`new Date().toISOString()`) instead of the archival fixture's frozen date -- the two clocks are independent and were wrongly conflated. Both fixes verified discriminating (reverting each reproduces its original failure). Full suites after: unit 8054/8054 (was 8053/8054), workers 761/761 locally (was 760/761). Test-only changes -- no production code touched. Filed and resolved: idea 01M1S79XZMF4Q9H53MQTCEQM0M (originally mis-filed as "pre-existing failures", corrected with the actual root cause). Co-Authored-By: Claude <noreply@anthropic.com>
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Follow-up triage on the latest Good news: everything flagged as unresolved in the previous two triage comments is now green — Only No code or PR-body changes made. Not touching the label or merging — that decision belongs to a human reviewer. |
2 participants
Summary
Fixes the chain that left deployments stuck on the
defanglabs.cainstall. Three defects, one incident, all in the deployment apply path.1. Concurrent app-route DNS creation 500'd the release fetch
GET /api/nodes/:id/deploy-releaseupserts every app-route DNS record before returning the node's release payload.upsertAppRouteDNSRecordwas a check-then-act with anawaitin the gap, fanned out viaPromise.all(deploy-release-callback.ts:306,328). Two callers both saw "no record", both POSTed, Cloudflare rejected the loser with 81058, and the throw propagated out ofPromise.all:The node never received its payload, so the deployment stalled upstream of anything cert-related. The missing certificate everyone could see was three layers downstream of the actual failure.
Fix: treat the duplicate-record codes on the create path as a lost race — re-resolve once, update in place. Scoped to 81057/81058 (81053, a cross-type collision, still throws), create-path only, bounded to one retry.
2. The same race in
createNodeBackendDNSRecord, with a worse failure modeFound by review against this PR's own new rule (§6: check sibling operations in the same module) — which this PR had not applied to its own module. It was a blind POST with no lookup at all. Two paths create that record; on conflict
node-lifecycle.ts:460stampsnodes.error_messageand leavesbackend_dns_record_idNULL, so every later heartbeat retried the same losing POST forever (no backfill job exists) and node deletion, which deletes by that id, orphaned the real record. Now resolves the winner so the id gets persisted, fixing both.3. The duplicate spawn that caused the race
health.gospawned a new apply goroutine per heartbeat per pending release with no in-flight check.observed.AppliedSeqonly advances after a fully successful apply, so any release slower than one heartbeat interval accumulated another concurrent apply per tick — each re-running the whole control-plane fetch.4. Compose SIGKILLed mid-pull by the apply idle watchdog
The apply is bounded by a 15-minute idle timer reset only by
ApplyProgressEvents.docker compose upemits exactly one (compose_up_started) and then nothing until it returns, so a legitimately slow image pull was indistinguishable from a hung apply. This is what producedcompose up: … signal: killed (stderr: db Pulling …).Compose streams pull progress to stderr, so that is now the liveness signal —
runComposewraps stderr in alivenessWriterthat pokes the watchdog per write without persisting an event, mirroringnewIdleProgressReaderwhich already does this for artifact downloads. Also fixed the diagnostic that hid it:health.gooverwrote the accurate"deployment apply stalled: no progress for 15m0s"with the child'ssignal: killed— a consequence of our own cancel — making a self-inflicted timeout indistinguishable from an OOM kill.5.
deployment_volumes.statusfrozen at the provider's transient snapshotattachEnvironmentVolumespersistedattached.statusstraight from the provider's response. Hetzner commonly still reportscreatingat that instant, and nothing ever re-polls the row — the only other writer is the detach path. So an attached, mounted, working volume readcreatingforever.Nothing reads the column, so this is not a functional bug. It is worse in a specific way: it is the single most obvious "here is your stuck deployment" signal in the table, and it is false. It cost real time in this investigation before code reading showed the heartbeat gate keys on
attached_server_id, notstatus.Now persists the settled SAM-side fact (
attached). No migration, no constraint widening — the column is plainTEXTwith noCHECK, andattachedis already in the provider'sVolumeStatusunion. Rule 57 at the storage layer; polling was rejected as disproportionate since the fact is knowable locally the moment attach returns.Live production evidence
From
deployment_release_eventsfor envpr18-preview-3, one node, while this branch was being written:An exact 2:1 fetch/apply ratio, still holding after 2.5 hours of looping — the duplicate's
Apply()is rejected by the engine'sapplyMu.TryLock(), which is why applies are half the fetches, but the fetch has already run and the fetch is what upserts DNS. 18 chances to lose the race on one environment. And 9 compose starts with zero completions, cycling every ~14 minutes against a 15-minute idle timeout.Validation
pnpm lint— clean on changed filespnpm typecheck— cleanpnpm test— API unit suite 8054/8054, 0 collection errors, total reconciled 8043 → 8054 (+11).vitest.workers.config.ts) — 761/761, 0 collection errors.Both CI test jobs are now green. Two failures showed up in earlier runs on this branch (
TestandDurable Object Workers). I initially reported them as "pre-existing, unrelated" — true, but incomplete: I had verified them as failing on a cleanmainbaseline, but hadn't found why. Root-caused and fixed in a follow-up commit, test-only, no production code touched:project-data-snapshot-recovery-wake.test.ts→allows a stopped ProjectData session to wake…NOW = 2026-08-26;expires_atseeded atNOW + 7 days = 2026-09-02. The production function (hasAuthorizedRestorableSnapshotWakeClaim) has no injectable clock and defaults to realnew Date(). Once real time passed 2026-09-02,expires_at > nowwent false — a time bomb, not a flake.NOW(vi.useFakeTimers/setSystemTime), so the production default resolves to the intended fixture time.project-data-tool-payload-archive.test.ts→retrieves archived tool payloads through the MCP tool(401not200)FIXED_NOW(2026-08-26) is correctly threaded through the archival business logic'snow/nowMsparams — but this one test also stamped an MCP token'screatedAtwith that same fixed date.validateMcpTokenhas no injectable clock by design (auth boundary) and rejects tokens older than 24h against realDate.now(). Once real time passed 2026-08-27 the token looked ~10 days old → 401. Two independent clocks, wrongly conflated.Both fixes verified discriminating: reverting either reproduces its original failure exactly, with no effect on the other tests in the same file. Neither touches DNS, deployment apply, compose, or volumes — the actual scope of this PR. Filed and closed as idea
01M1S79XZMF4Q9H53MQTCEQM0M(originally mis-filed as "pre-existing failures" before the root cause was found).go build,go vet,gofmtclean on all touched files; 23/23 packages pass;deploy+serverpass-raceEvery guard proven discriminating
Each mutation applied once, observed, reverted:
!existingremoved (widen to update path)code: v.optional(v.number())restoreddns.ts+ route suiteThe fifth row is the one that matters most: the existing route suite could not observe the production 500. Only a test at the real entry point can.
Staging Verification (REQUIRED — merge-blocking)
Staging Verification Evidence
Not performed. This is a merge blocker under
.claude/rules/13and/22, and a human must decide how to proceed. I am deliberately not checking these boxes rather than rationalizing them (.claude/rules/30).Two reasons:
deploy-staging.ymltargets the upstreamsammy.partyenvironment, not this fork'sdefanglabs.cadeployment.packages/vm-agent/, so.claude/rules/27applies: VM agent binaries are downloaded once at cloud-init. Verifying the Go changes requires deleting all nodes, deploying so the new binary reaches R2, and provisioning a fresh node. Testing against an existing node would exercise the old binary and prove nothing.What is verified: the production failure was root-caused from live D1 and Cloudflare state (the error row, the zone's DNS records, the duplicated
seq=4, the 2:1 fetch/apply ratio), and every fix has a regression test proven to fail against the pre-fix code.Suggested verification once deployed: delete all nodes → deploy → provision fresh → confirm
deployment_release_eventsshows a 1:1 fetch/apply ratio (not 2:1),compose_up_completedappears, and a grey-cloudr{N}-…apps.{BASE_DOMAIN}A record resolves to the node IP.Post-Mortem
What broke
Deployments stalled indefinitely with no app-route DNS record and no TLS certificate; later attempts failed with
signal: killedduringdocker compose up.Root cause
Check-then-act against an external API that enforces its own uniqueness constraint, with the conflict treated as fatal on a path that gates an entire deployment — plus a duplicate-spawn bug that made the race far likelier, and a watchdog blind to the longest step it was guarding.
Class of bug
Two, from one incident:
awaitinterleaving). A mutex isn't proportionate when the remote API adjudicates in one round trip — converge on its answer. Review then showed the overlap was also preventable one layer up, so this PR does both: remove the cause, and survive it anyway (old agents keep retrying until replaced — rule 54).Why it wasn't caught
Existing tests covered create-when-absent and update-when-present — the two sequential outcomes. Nothing exercised two callers interleaving, despite the only production call site being a
Promise.allfan-out. And no test existed at the route, so all 31 route tests passed while the endpoint 500'd in production.Process fix included in this PR
.claude/rules/68-external-api-check-then-act.md(new) — its §6 immediately caught the second live instance fixed here..claude/rules/53§5c (extended, not forked — same family) — "which step is the longest, and does it emit the signal the timer listens for?", plus the two traps found while fixing it.Post-mortem file
tasks/active/2026-09-05-fix-app-route-dns-upsert-race.mdSpecialist Review Evidence
v.optional(v.number())rejectscode: null/stringified, silently degrading error messages for 5 untouched callers → fixed7db98bfb. 2 LOW (subrequest/latency budget) verified benign, documented.createNodeBackendDNSRecordsibling with a worse failure mode → fixed0ee9dd5e. (2) vm-agent duplicate apply spawns, with an unused dedup primitive already present → fixed7625486e. MEDIUMs: rule wording overclaimed "a mutex cannot help"; retry bound was the only unnamed limit inapps/api/src→ both fixed.!existingguard — the suite stayed green when widened; (2) no route-level test — pre-fix code passed all 31. Both fixed0ee9dd5e. MEDIUM: the fan-out test was scripted, not a real race → replaced with a shared-store same-hostname race.livenessWriterretained the head of compose output, contradicting its own doc comment — compose prints the failure on its last lines, so the cap discarded exactly the diagnostic being preserved → fixed9e43ad74with tail retention + 2 content-asserting tests. Verified no deadlock across the 4 mutexes, no goroutine leak, correctdefersemantics, and (against Go 1.26.6 stdlib source) thatcmd.Wait()rules out the custom-writer race. 2 LOW (dead test code, overstated panic comment) fixed.Known limitations (deliberate, stated)
GET /deploy-releaseis retry-tolerant by design, and already-deployed agents keep retrying until replaced (rule 54). Defence in depth: the guard removes the cause, the tolerance survives it.fetch_startedevents were 1 second apart, which does not match the 60sHEARTBEAT_INTERVAL. The 2:1 ratio above is what the goroutine-per-heartbeat bug predicts, but the 1-second spacing suggests a second trigger that was not identified. The dedup guard closes the window regardless, since it keys on the job id rather than the caller.deployment_volumes.statusis written once from the provider's transient attach response and never re-polled, so an attached volume readscreatingforever. Cosmetic — the heartbeat gate keys onattached_server_id, notstatus— but it misled this investigation and will mislead the next. Filed as an idea; unrelated to this chain and needs its own provider-polling design.Agent Preflight (Required)
Classification
External References
Context7 was not available in this environment; official primary documentation and independent reference implementations were used instead, as
.claude/rules/05permits.Cloudflare's numeric DNS error codes are not published in its API reference, so they were corroborated against five independent production consumers rather than a single source:
certbot-dns-cloudflare—ERR_RECORD_EXISTS = 81057,ERR_IDENTICAL_RECORD_EXISTS = 81058: https://github.com/certbot/certbot/blob/master/certbot-dns-cloudflare/certbot_dns_cloudflare/_internal/dns_cloudflare.pyA live call to the Cloudflare API confirmed
codeis emitted as a bare JSON integer (never quoted), which is what thetypeof === 'number'narrowing relies on.Go
os/exec(official source, 1.26.6) read directly to confirmCmd.Wait()blocks on<-c.goroutineErruntil every I/O-copier goroutine has finished — the guarantee thelivenessWriterdesign depends on for safe buffer reads aftercmd.Run()returns: https://github.com/golang/go/blob/master/src/os/exec/exec.goCodebase Impact Analysis
apps/api/src/services/dns.ts—upsertAppRouteDNSRecord,createNodeBackendDNSRecord,readCloudflareErrorDetailpackages/vm-agent/internal/server/—health.go,vm_jobs.go(claimJob),server.go(inFlightJobs)packages/vm-agent/internal/deploy/—compose.go(livenessWriter),engine.go,engine_config.godeploy-release-callback.ts:306,328,node-lifecycle.ts:446,nodes.ts:373Documentation & Specs
N/A: internal service behavior only — no public API, env var, or setup step changed.Process documentation added as.claude/rules/68-external-api-check-then-act.mdand.claude/rules/53§5c.Constitution & Risk Check
Principle XI (No Hardcoded Values) — checked, and it changed the code. The retry bound was initially a bare
attempt >= 1; review flagged it as the only unnamed retry limit inapps/api/srcagainst 15+ named siblings inenv.ts, so it is nowDNS_UPSERT_RACE_MAX_RETRIES. It is deliberately NOT env-exposed: it bounds an internal recovery loop against a constraint that resolves in a single round trip, not a caller-facing policy.composeOutputRetentionBytesis likewise a named constant. The vm-agent idle timeout it interacts with (DEPLOY_APPLY_IDLE_TIMEOUT/DefaultDeployApplyIdleTimeout) was already env-configurable and is unchanged.CF_DNS_DUPLICATE_RECORD_CODESis a curated static table of provider error codes — data, not configuration.Principle XIII (Fail Fast) — the tolerance is deliberately narrow so failing fast is preserved where it matters: only 81057/81058, only on the create path, bounded to one retry. 81053 (cross-type collision), auth, and quota errors all still throw, each with a dedicated control test.
Key risks and tradeoffs:
defer, an idempotent release, and a test proving a retry of the same seq after completion is allowed. Worst case degrades to the pre-existing behaviour (an apply is skipped and re-advertised on the next heartbeat)..claude/rules/27and cannot be exercised from here.🤖 Generated with Claude Code