## What
Routes the webapp write path through the run-ops split seam:
trigger/batch minting, idempotency-key resolution, and the run-lifecycle
services now determine residency and dispatch writes to the correct
store.
- **Trigger & batch** (`runEngine/services/triggerTask.server.ts`,
`batchTrigger.server.ts`, `createBatch.server.ts`,
`streamBatchItems.server.ts`, `v3/services/batchTriggerV3.server.ts`):
mint ids with the run-ops-aware minting and route creation/streaming
through the store; batch children inherit the parent's residency.
- **Idempotency** (`runEngine/concerns/idempotencyKeys.server.ts` + new
`idempotencyResidency.server.ts`): idempotency-key lookup/dedup is
residency-aware so a keyed retrigger resolves against the store that
owns the original run.
- **Run lifecycle services** (`createCheckpoint`,
`createTaskRunAttempt`, `enqueueDelayedRun`, `expireEnqueuedRun`,
`finalizeTaskRun`, `resumeBatchRun`, `cancelDevSessionRuns`,
`executeTasksWaitingForDeploy`, `triggerFailedTask`): resolve their
target run through the store rather than a fixed client.
- **Reads that fan out from writes** (`runsRepository` +
`clickhouseRunsRepository`, `BulkActionV2` + batch read-through,
realtime `sessions`/`runReader`, alerts
`deliverAlert`/`performTaskRunAlerts`): route through the read-through
resolver.
- `9535ae63d` — resolves the parent run through an injectable run store
in `TriggerFailedTaskService`.
- `bf8f7c881` — drops the "known-migrated" concept from write-path and
read repos; residency is id-shape only.
- `515b897ea` — self-defaults `resolveWaitpointThroughReadThrough` to
the safe run-ops clients.
## Why
PR6 of the run-ops split stack. This is the write-path counterpart to
the read foundation in the previous PRs: with it in place, both reads
and writes route through the seam. Additive when the split is disabled
(id-shape resolution collapses to the control-plane client);
behavior-changing on the minting, idempotency, and lifecycle paths when
enabled.
## Tests
Large new/expanded vitest suite under `apps/webapp/test/` and colocated
service tests: trigger-task and batch-trigger store routing, residency
inheritance, idempotency dedup residency + legacy-authority, bulk-action
read routing, cancel-dev-session routing, alerts store routing,
runs-repository read-through, realtime session/run-reader read-through
and stream-registration routing, and the waitpoint read-through default.
Testcontainers-backed; no mocks.
## Notes
Draft, **stacked on #4117** (`runops/pr05-webapp-foundation`). Review
that first; this diff is against it.
Server-change / changeset note to be added at stack-assembly time.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
## Summary
The trigger hot path's mollifier integration:
- `mollifyTrigger`: when the gate trips, write the engine.trigger
snapshot to the buffer and return a synthesised QUEUED response.
Postgres write is deferred to drainer-replay (next PR in the stack).
- Pre-gate idempotency-key claim: same-key triggers serialise through
Redis so a burst lands in PG / buffer exactly once.
- Read-fallback extensions: `findRunByIdWithMollifierFallback` for the
trigger-time idempotency lookup that must see buffered runs.
- Gate bypasses: `debounce`, `oneTimeUseToken`,
`parentTaskRunId`/`triggerAndWait` skip the mollify path entirely.
- `triggerTask` + `IdempotencyKeyConcern` wired to the above.
All behaviour gated by the master `TRIGGER_MOLLIFIER_ENABLED` switch;
off-state hot path is unchanged (the gate is not even consulted).
Stacked on the buffer extensions PR.
## Test plan
- [x] \`pnpm run typecheck --filter webapp\` passes
- [x] \`pnpm run test --filter webapp test/mollifierMollify.test.ts\`
passes
- [x] \`pnpm run test --filter webapp
test/mollifierIdempotencyClaim.test.ts\` passes
- [x] \`pnpm run test --filter webapp
test/mollifierReadFallback.test.ts\` passes
- [x] \`pnpm run test --filter webapp test/mollifierGate.test.ts\`
passes
- [x] \`pnpm run test --filter webapp test/engine/triggerTask.test.ts\`
passes
---
## Ship-gate follow-up fixes
- **Batch items bypass the mollifier gate** — fixes
`BatchTaskRunItem_taskRunId_fkey` FK violation on batch triggers when
the gate trips. End-state is a drainer-side `BatchTaskRunItem`
create-on-materialise; batch traffic passes through the gate until that
lands.
- **IdempotencyKeyConcern honours buffered-run TTL on expiry** —
buffered path now clears expired idempotency claims (read-side) and
resets the buffer's `mollifier:idempotency:*` SETNX binding (write-side)
so a re-trigger past the customer's TTL lands as a fresh run instead of
echoing the stale buffered runId.
---------
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Daniel Sutton