One http.server span per request: the worker defers to Effect's tracer#985
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Every API/MCP request produced TWO identical sibling http.server spans: the worker-boundary span server.ts opens (scope executor-cloud-worker) AND the one Effect's HttpMiddleware.tracer opens for app-owned paths (scope executor-cloud) — both joined the caller's traceparent, so the waterfall showed a childless twin next to the real envelope, and server span ingest was doubled (visible in Axiom: 39.7k executor-cloud vs 24.9k executor-cloud-worker spans on /mcp alone). The worker now skips its span for app-owned paths (app-paths.ts: /api/*, /mcp, /.well-known/*) — Effect's middleware already parses traceparent and parents the workos/store/db children there. Non-app paths (Start SSR, marketing proxy, /_astro assets) keep the worker envelope span, and the flush-on-waitUntil still runs on both branches so batched exports survive the isolate. Verified against the suite motel: API scenario + browser scenario runs now record exactly one http.server per trace (worker scope only on / and SSR routes), browser→server join intact (executor-web client span → executor-cloud server span → workos/user_store/fumadb children); cloud observability unit tests green. Found via the prod Axiom dataset right after #981 made browser traces land — the duplicate was previously invisible without the join.
Deploying with
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| Status | Name | Latest Commit | Updated (UTC) |
|---|---|---|---|
| ✅ Deployment successful! View logs |
executor-cloud | 60a39bf | Jun 12 2026, 06:33 PM |
Deploying with
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| Status | Name | Latest Commit | Preview URL | Updated (UTC) |
|---|---|---|---|---|
| ✅ Deployment successful! View logs |
executor-marketing | 60a39bf | Commit Preview URL Branch Preview URL |
Jun 12 2026, 06:32 PM |
Contributor
Cloudflare previewTorn down — the PR is closed. |
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The bug
Every API/MCP request produced two identical sibling
http.serverspans: the worker-boundary spanserver.tsopens (scopeexecutor-cloud-worker) and the one Effect'sHttpMiddleware.traceropens for app-owned paths (scopeexecutor-cloud). Both join the caller'straceparent, so they land in the same trace as twins — the waterfall shows a childless duplicate next to the real envelope (all the workos/store/db children parent under Effect's span), and server-span ingest is doubled. In the production dataset that's ~25k duplicate spans against ~40k real ones on/mcpalone.The duplicate was invisible until the browser span export landed (#981) and made joined traces inspectable end to end — the first real waterfall showed the twin immediately.
The fix
The worker now skips its envelope span for app-owned paths (
app-paths.ts:/api/*,/mcp,/.well-known/*) — Effect's middleware already parsestraceparentitself and parents the child spans there. Non-app paths (Start SSR, the marketing proxy,/_astroassets — which Effect never sees) keep the worker span, and the flush-on-waitUntilruns on both branches so batched exports survive the isolate.After deploy,
executor-cloud-worker-scope server spans become a meaningful signal ("non-app traffic") instead of noise.Verified
Against the suite-owned motel trace store (#979): API + browser scenario runs record exactly one
http.serverspan per trace (worker scope appears only on/and SSR routes), and the browser→server join is intact —executor-webclient span →executor-cloudserver span →workos/user_store/fumadbchildren. Cloud observability unit tests 10/10; lint/format/typecheck clean.