Next.js v11 build-time instrumentation: Turbopack build timeout and opt-out trace coverage #24764

Environment

• @sentry/nextjs 11.0.0
• Next.js 16.3.6, Turbopack production build
• pnpm workspace monorepo
• Vercel build machine: 4 cores, 8 GB

Observed regression

Our first production Git deployment upgrading from Sentry 10 to 11 stopped at Creating an optimized production build and was terminated with BUILD_EXCEEDED_MAXIMUM_TIME (45 minutes). The preceding build, also without cache, compiled in 2.2 minutes. There is no explicit Vercel OOM error.

Isolation and mitigation

A clean local build with 4-CPU affinity, an 8-GB memory cgroup, no swap, and production environment completed with only buildTimeInstrumentation: false changed (98-second compilation).

We inspected maybeAddOrchestrionRule in constructTurbopackConfig: the *.{js,mjs,cjs} rule has condition node. An experimental local patch added a node_modules path condition derived from getSentryInstrumentations() module names. A subsequent clean source build on Vercel compiled in 107 seconds and completed in 4m15s; AI SDK/OpenAI/Anthropic registration calls were present in generated output. This suggests the broad loader rule may contribute, but we have not profiled the precise bottleneck or produced a public minimal reproduction.

We are removing that custom patch and using the supported buildTimeInstrumentation: false option while investigating.

Questions

1. Is excessive Turbopack loader work with the default Orchestrion rule a known v11 issue? Is package-level filtering supported or planned?
2. Which automatic server traces are lost with buildTimeInstrumentation: false on Vercel, particularly bundled AI SDK 7, OpenAI and Anthropic SDKs, and database clients? Which still work through runtime channels or Next.js instrumentation?
3. Is there a supported selective option to preserve these integrations without passing every server JavaScript module through the loader?
4. What profiling output or minimal reproduction would be most useful?

Error reporting, source map upload and explicit application spans remain configured. We are not claiming this mitigation preserves all automatic trace coverage.