module: remove --experimental-transform-types - #61803

marco-ippolito · 2026-02-13T16:37:18Z

This PR removes the --experimental-transform-types flag and all related code, tests, and documentation.

nodejs-github-bot · 2026-02-13T16:37:23Z

Review requested:

GeoffreyBooth · 2026-02-13T17:03:11Z

process.features.typescript now only returns a boolean

I think we should add process.features.stripTypes that returns a boolean. This should be a separate PR so that it can be backported.

Then the question becomes what to do with process.features.typescript. I think having a feature called typescript only makes sense if the overall feature has various modes, like currently it's either off (false), strip or transform. But we might someday add other TypeScript-related features like type checking, or tsconfig.json support, or support for various features within tsconfig.json; and these might be individual features to be toggled on or off (like maybe a user enables tsconfig.json paths support but not type checking) and so a single string value for an overall mode doesn't make sense. We could make process.features.typescript a Record<string, boolean> so that there's something like process.features.typescript.strip === true and other features add onto there, or treat each new TypeScript-related feature as a top-level key on process.features.

For the purposes of this PR, perhaps the simplest thing to do would be to just keep process.features.typescript as it is but remove transform as a possible return type. Then a redesign of process.features.typescript can happen in a dedicated PR.

marco-ippolito · 2026-02-13T17:04:51Z

User can run --no-strip-types so typescript might not be enabled

aduh95 · 2026-02-13T17:45:37Z

process.features.typescript now only returns a boolean.

I wouldn't do that:

it's perfectly workable as is, as a string
if we end up re-introducing --transform-type or another type of typescript handling, it will put us in an awkard position.

Why risk it?

styfle · 2026-02-13T18:08:38Z

if we end up re-introducing --transform-type or another type of typescript handling, it will put us in an awkard position.

If we think thats a possibility in the future, then we should keep process.features.typescript as a string and also keep the options object in stripTypeScriptTypes() so we can allow strip but throw and error for other modes.

TLDR - keep this semver-major change as breaking only for those using transform but anyone using strip should not have a breaking change. Does that make sense?

codecov · 2026-02-13T18:34:53Z

Codecov Report

❌ Patch coverage is 66.66667% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.66%. Comparing base (da5efc4) to head (1708c57).
⚠️ Report is 35 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/internal/modules/typescript.js	75.00%	1 Missing ⚠️
src/compile_cache.cc	0.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #61803      +/-   ##
==========================================
+ Coverage   88.84%   89.66%   +0.82%     
==========================================
  Files         674      676       +2     
  Lines      204957   205951     +994     
  Branches    39309    39434     +125     
==========================================
+ Hits       182087   184670    +2583     
+ Misses      15088    13426    -1662     
- Partials     7782     7855      +73

Files with missing lines	Coverage Δ
lib/internal/bootstrap/node.js	`98.96% <100.00%> (-0.01%)`	⬇️
src/compile_cache.h	`100.00% <ø> (ø)`
src/node_options.cc	`76.32% <ø> (-0.05%)`	⬇️
lib/internal/modules/typescript.js	`92.30% <75.00%> (-5.18%)`	⬇️
src/compile_cache.cc	`79.09% <0.00%> (-1.64%)`	⬇️

... and 210 files with indirect coverage changes

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GeoffreyBooth · 2026-02-13T19:58:22Z

This PR's goal is to remove transform-types. So in this PR, I think just remove the transform response from process.features.typescript. Any other rethinking or redesign of that property can come in a follow-up PR.

marco-ippolito · 2026-02-23T16:09:35Z

Applied suggestions, only remove transform related stuff

ljharb

LGTM overall

marco-ippolito · 2026-02-23T23:29:43Z

Cna someone help me understand the CI failure?

Renegade334 · 2026-02-25T21:42:11Z

Cna someone help me understand the CI failure?

The --[experimental-]strip-types CLI flag needs to be reintroduced here:

https://github.com/nodejs/node/blob/50a77dbaa26fd58460d1bee1de317047d1462a5f/test/parallel/test-runner-cli.js#L67-L68

aduh95 · 2026-02-26T08:06:35Z

Cna someone help me understand the CI failure?

The --experimental-strip-types CLI flag needs to be reintroduced here:

That doesn't really make sense, type stripping has been unflagged for a while, that flag is now a no-op. The issue seems to be that the following branch is no longer needed:

https://github.com/nodejs/node/blob/50a77dbaa26fd58460d1bee1de317047d1462a5f/test/parallel/test-runner-cli.js#L71-L74

assert: * (SEMVER-MAJOR) allow printf-style messages as assertion error (Ruben Bridgewater) #58849 build: * (SEMVER-MAJOR) bump GCC requirement to 13.2 (Michaël Zasso) #62555 * (SEMVER-MAJOR) enable Temporal by default (Richard Lau) #61806 * (SEMVER-MAJOR) enable V8_VERIFY_WRITE_BARRIERS in debug build (Joyee Cheung) #61898 * (SEMVER-MAJOR) reset embedder string to "-node.0" (Michaël Zasso) #61898 * (SEMVER-MAJOR) target Power 9 for AIX/IBM i (Richard Lau) #62296 * (SEMVER-MAJOR) drop support for Python 3.9 (Mike McCready) #61177 * (SEMVER-MAJOR) enable maglev for Linux on s390x (Richard Lau) #60863 * (SEMVER-MAJOR) reset embedder string to "-node.0" (Michaël Zasso) #60488 * (SEMVER-MAJOR) reset embedder string to "-node.0" (Michaël Zasso) #60111 build,test: * (CVE-2026-21717) (SEMVER-MAJOR) test array index hash collision (Joyee Cheung) #61898 build,win: * (SEMVER-MAJOR) fix Temporal build (StefanStojanovic) #61806 crypto: * (SEMVER-MAJOR) unify asymmetric key import through KeyObjectHandle::Init (Filip Skokan) #62499 * (SEMVER-MAJOR) runtime-deprecate DEP0203 and DEP0204 (Filip Skokan) #62453 * (SEMVER-MAJOR) decorate async crypto job errors with OpenSSL error details (Filip Skokan) #62348 * (SEMVER-MAJOR) default ML-KEM and ML-DSA pkcs8 export to seed-only format (Filip Skokan) #62178 * (SEMVER-MAJOR) move DEP0182 to End-of-Life (Tobias Nießen) #61084 * (SEMVER-MAJOR) fix DOMException name for non-extractable key error (Filip Skokan) #60830 deps: * (SEMVER-MAJOR) fix V8 race condition for AIX (Abdirahim Musse) #61898 * (SEMVER-MAJOR) V8: cherry-pick cd2c216e7658 (LuYahan) #61898 * (SEMVER-MAJOR) V8: backport 088b7112e7ab (Igor Sheludko) #61898 * (SEMVER-MAJOR) V8: cherry-pick 00f6e834029f (Joyee Cheung) #61898 * (SEMVER-MAJOR) V8: backport bef0d9c1bc90 (Joyee Cheung) #61898 * (SEMVER-MAJOR) V8: cherry-pick cf1bce40a5ef (Richard Lau) #61898 * (SEMVER-MAJOR) V8: cherry-pick daf4656ba85e (Milad Fa) #61898 * (SEMVER-MAJOR) V8: cherry-pick d83f479604c8 (Joyee Cheung) #61898 * (SEMVER-MAJOR) V8: cherry-pick edeb0a4fa181 (Joyee Cheung) #61898 * (SEMVER-MAJOR) V8: cherry-pick aa0b288f87cc (Richard Lau) #61898 * (SEMVER-MAJOR) patch V8 to fix Windows build (StefanStojanovic) #61898 * (SEMVER-MAJOR) V8: cherry-pick highway@989a498fdf3 (Richard Lau) #61898 * (SEMVER-MAJOR) support madvise(3C) across ALL illumos revisions (Dan McDonald) #61898 * (SEMVER-MAJOR) patch V8 for illumos (Dan McDonald) #61898 * (SEMVER-MAJOR) remove problematic comment from v8-internal (Michaël Zasso) #61898 * (SEMVER-MAJOR) define V8_PRESERVE_MOST as no-op on Windows (Stefan Stojanovic) #61898 * (SEMVER-MAJOR) patch V8 to avoid duplicated zlib symbol (Michaël Zasso) #61898 * (SEMVER-MAJOR) update V8 to 14.6.202.33 (Michaël Zasso) #61898 * (SEMVER-MAJOR) update undici to 8.0.2 (Node.js GitHub Bot) #62384 * (SEMVER-MAJOR) V8: backport 151d0a44a1b2 (Abdirahim Musse) #60488 * (SEMVER-MAJOR) V8: cherry-pick 47800791b35c (Jakob Kummerow) #60488 * (SEMVER-MAJOR) patch V8 for illumos (Dan McDonald) #59805 * (SEMVER-MAJOR) use std::map in MSVC STL for EphemeronRememberedSet (Joyee Cheung) #58070 * (SEMVER-MAJOR) remove problematic comment from v8-internal (Michaël Zasso) #58070 * (SEMVER-MAJOR) patch V8 to avoid duplicated zlib symbol (Michaël Zasso) #54077 * (SEMVER-MAJOR) update V8 to 14.3.127.12 (Michaël Zasso) #60488 * (SEMVER-MAJOR) V8: cherry-pick ff34ae20c8e3 (Chengzhong Wu) #60111 * (SEMVER-MAJOR) V8: backport fed47445bbdd (Abdirahim Musse) #60111 * (SEMVER-MAJOR) patch V8 for illumos (Dan McDonald) #59805 * (SEMVER-MAJOR) use std::map in MSVC STL for EphemeronRememberedSet (Joyee Cheung) #58070 * (SEMVER-MAJOR) remove problematic comment from v8-internal (Michaël Zasso) #58070 * (SEMVER-MAJOR) patch V8 to avoid duplicated zlib symbol (Michaël Zasso) #54077 * (SEMVER-MAJOR) update V8 to 14.2.231.9 (Michaël Zasso) #60111 diagnostics_channel: * (SEMVER-MAJOR) ensure tracePromise consistency with non-Promises (René) #61766 doc: * (SEMVER-MAJOR) remove extensionless CJS exception for type:module packages (Matteo Collina) #62176 * (SEMVER-MAJOR) update supported Windows SDK version to 11 (Mike McCready) #61973 * (SEMVER-MAJOR) drop p8 and z13 support (Milad Fa) #61005 http: * (SEMVER-MAJOR) move writeHeader to end-of-life (Sebastian Beltran) #60635 * (SEMVER-MAJOR) fix handling of HTTP upgrades with bodies (Tim Perry) #60016 lib: * (SEMVER-MAJOR) return undefined for localStorage without file (Matteo Collina) #61333 lib,src: * (SEMVER-MAJOR) implement QuotaExceededError as DOMException-derived interface (Filip Skokan) #62293 module: * (SEMVER-MAJOR) runtime-deprecate module.register() (Geoffrey Booth) #62401 * (SEMVER-MAJOR) remove --experimental-transform-types (Marco Ippolito) #61803 src: * (SEMVER-MAJOR) replace uses of deprecated v8::External APIs (gahaas) #61898 * (SEMVER-MAJOR) stop using `v8::PropertyCallbackInfo<T>::This()` (Igor Sheludko) #61898 * (SEMVER-MAJOR) avoid deprecated Wasm API (Clemens Backes) #61898 * (SEMVER-MAJOR) avoid deprecated `FixedArray::Get` (Clemens Backes) #61898 * (SEMVER-MAJOR) update NODE_MODULE_VERSION to 147 (Michaël Zasso) #61898 * (SEMVER-MAJOR) remove deprecated and unused isolate fields (Michaël Zasso) #60488 * (SEMVER-MAJOR) update NODE_MODULE_VERSION to 144 (Michaël Zasso) #60488 * (SEMVER-MAJOR) include `node_api_types.h` instead of `node_api.h` in `node.h` (Anna Henningsen) #60496 * (SEMVER-MAJOR) update NODE_MODULE_VERSION to 142 (Michaël Zasso) #60111 stream: * (SEMVER-MAJOR) promote DEP0201 to runtime deprecation (René) #62173 * (SEMVER-MAJOR) move _stream_* to end-of-life (Sebastian Beltran) #60657 * (SEMVER-MAJOR) readable read one buffer at a time (Robert Nagy) #60441 * (SEMVER-MAJOR) preserve AsyncLocalStorage on finished only when needed (avcribl) #59873 test: * (SEMVER-MAJOR) skip wasm allocation tests in workers (Michaël Zasso) #61898 * (SEMVER-MAJOR) update wpt Wasm jsapi expectations (Michaël Zasso) #61898 * (SEMVER-MAJOR) support presence of Temporal global (Michaël Zasso) #61898 * (SEMVER-MAJOR) add type tags to uses of v8::External (gahaas) #61898 * (SEMVER-MAJOR) fix test-linux-perf-logger for V8 14.3 (Michaël Zasso) #60488 tools: * (SEMVER-MAJOR) remove v8_initializers_slow workaround from v8.gyp (Michaël Zasso) #61898 * (SEMVER-MAJOR) add Rust args to `tools/make-v8.sh` (Richard Lau) #61898 * (SEMVER-MAJOR) update V8 gypfiles for 14.6 (Michaël Zasso) #61898 * (SEMVER-MAJOR) update V8 gypfiles for 14.5 (Michaël Zasso) #61898 * (SEMVER-MAJOR) update V8 gypfiles for 14.4 (Michaël Zasso) #61898 util: * (SEMVER-MAJOR) mark proxied objects as such when inspecting them (Ruben Bridgewater) #61029 * (SEMVER-MAJOR) reduce TextEncoder.encodeInto function size (Yagiz Nizipli) #60339 PR-URL: #62526

assert: * (SEMVER-MAJOR) allow printf-style messages as assertion error (Ruben Bridgewater) #58849 build: * (SEMVER-MAJOR) bump GCC requirement to 13.2 (Michaël Zasso) #62555 * (SEMVER-MAJOR) enable Temporal by default (Richard Lau) #61806 * (SEMVER-MAJOR) enable V8_VERIFY_WRITE_BARRIERS in debug build (Joyee Cheung) #61898 * (SEMVER-MAJOR) reset embedder string to "-node.0" (Michaël Zasso) #61898 * (SEMVER-MAJOR) target Power 9 for AIX/IBM i (Richard Lau) #62296 * (SEMVER-MAJOR) drop support for Python 3.9 (Mike McCready) #61177 * (SEMVER-MAJOR) enable maglev for Linux on s390x (Richard Lau) #60863 * (SEMVER-MAJOR) reset embedder string to "-node.0" (Michaël Zasso) #60488 * (SEMVER-MAJOR) reset embedder string to "-node.0" (Michaël Zasso) #60111 build,test: * (CVE-2026-21717) (SEMVER-MAJOR) test array index hash collision (Joyee Cheung) #61898 build,win: * (SEMVER-MAJOR) fix Temporal build (StefanStojanovic) #61806 crypto: * (SEMVER-MAJOR) unify asymmetric key import through KeyObjectHandle::Init (Filip Skokan) #62499 * (SEMVER-MAJOR) runtime-deprecate DEP0203 and DEP0204 (Filip Skokan) #62453 * (SEMVER-MAJOR) decorate async crypto job errors with OpenSSL error details (Filip Skokan) #62348 * (SEMVER-MAJOR) default ML-KEM and ML-DSA pkcs8 export to seed-only format (Filip Skokan) #62178 * (SEMVER-MAJOR) move DEP0182 to End-of-Life (Tobias Nießen) #61084 * (SEMVER-MAJOR) fix DOMException name for non-extractable key error (Filip Skokan) #60830 deps: * (SEMVER-MAJOR) V8: cherry-pick 0f024d4e66e0 (ishabi) #62408 * (SEMVER-MAJOR) fix V8 race condition for AIX (Abdirahim Musse) #61898 * (SEMVER-MAJOR) V8: cherry-pick cd2c216e7658 (LuYahan) #61898 * (SEMVER-MAJOR) V8: backport 088b7112e7ab (Igor Sheludko) #61898 * (SEMVER-MAJOR) V8: cherry-pick 00f6e834029f (Joyee Cheung) #61898 * (SEMVER-MAJOR) V8: backport bef0d9c1bc90 (Joyee Cheung) #61898 * (SEMVER-MAJOR) V8: cherry-pick cf1bce40a5ef (Richard Lau) #61898 * (SEMVER-MAJOR) V8: cherry-pick daf4656ba85e (Milad Fa) #61898 * (SEMVER-MAJOR) V8: cherry-pick d83f479604c8 (Joyee Cheung) #61898 * (SEMVER-MAJOR) V8: cherry-pick edeb0a4fa181 (Joyee Cheung) #61898 * (SEMVER-MAJOR) V8: cherry-pick aa0b288f87cc (Richard Lau) #61898 * (SEMVER-MAJOR) patch V8 to fix Windows build (StefanStojanovic) #61898 * (SEMVER-MAJOR) V8: cherry-pick highway@989a498fdf3 (Richard Lau) #61898 * (SEMVER-MAJOR) support madvise(3C) across ALL illumos revisions (Dan McDonald) #61898 * (SEMVER-MAJOR) patch V8 for illumos (Dan McDonald) #61898 * (SEMVER-MAJOR) remove problematic comment from v8-internal (Michaël Zasso) #61898 * (SEMVER-MAJOR) define V8_PRESERVE_MOST as no-op on Windows (Stefan Stojanovic) #61898 * (SEMVER-MAJOR) patch V8 to avoid duplicated zlib symbol (Michaël Zasso) #61898 * (SEMVER-MAJOR) update V8 to 14.6.202.33 (Michaël Zasso) #61898 * (SEMVER-MAJOR) update undici to 8.0.2 (Node.js GitHub Bot) #62384 * (SEMVER-MAJOR) V8: backport 151d0a44a1b2 (Abdirahim Musse) #60488 * (SEMVER-MAJOR) V8: cherry-pick 47800791b35c (Jakob Kummerow) #60488 * (SEMVER-MAJOR) patch V8 for illumos (Dan McDonald) #59805 * (SEMVER-MAJOR) use std::map in MSVC STL for EphemeronRememberedSet (Joyee Cheung) #58070 * (SEMVER-MAJOR) remove problematic comment from v8-internal (Michaël Zasso) #58070 * (SEMVER-MAJOR) patch V8 to avoid duplicated zlib symbol (Michaël Zasso) #54077 * (SEMVER-MAJOR) update V8 to 14.3.127.12 (Michaël Zasso) #60488 * (SEMVER-MAJOR) V8: cherry-pick ff34ae20c8e3 (Chengzhong Wu) #60111 * (SEMVER-MAJOR) V8: backport fed47445bbdd (Abdirahim Musse) #60111 * (SEMVER-MAJOR) patch V8 for illumos (Dan McDonald) #59805 * (SEMVER-MAJOR) use std::map in MSVC STL for EphemeronRememberedSet (Joyee Cheung) #58070 * (SEMVER-MAJOR) remove problematic comment from v8-internal (Michaël Zasso) #58070 * (SEMVER-MAJOR) patch V8 to avoid duplicated zlib symbol (Michaël Zasso) #54077 * (SEMVER-MAJOR) update V8 to 14.2.231.9 (Michaël Zasso) #60111 diagnostics_channel: * (SEMVER-MAJOR) ensure tracePromise consistency with non-Promises (René) #61766 doc: * (SEMVER-MAJOR) remove extensionless CJS exception for type:module packages (Matteo Collina) #62176 * (SEMVER-MAJOR) update supported Windows SDK version to 11 (Mike McCready) #61973 * (SEMVER-MAJOR) drop p8 and z13 support (Milad Fa) #61005 http: * (SEMVER-MAJOR) move writeHeader to end-of-life (Sebastian Beltran) #60635 * (SEMVER-MAJOR) fix handling of HTTP upgrades with bodies (Tim Perry) #60016 lib: * (SEMVER-MAJOR) return undefined for localStorage without file (Matteo Collina) #61333 lib,src: * (SEMVER-MAJOR) implement QuotaExceededError as DOMException-derived interface (Filip Skokan) #62293 module: * (SEMVER-MAJOR) runtime-deprecate module.register() (Geoffrey Booth) #62401 * (SEMVER-MAJOR) remove --experimental-transform-types (Marco Ippolito) #61803 src: * (SEMVER-MAJOR) replace uses of deprecated v8::External APIs (gahaas) #61898 * (SEMVER-MAJOR) stop using `v8::PropertyCallbackInfo<T>::This()` (Igor Sheludko) #61898 * (SEMVER-MAJOR) avoid deprecated Wasm API (Clemens Backes) #61898 * (SEMVER-MAJOR) avoid deprecated `FixedArray::Get` (Clemens Backes) #61898 * (SEMVER-MAJOR) update NODE_MODULE_VERSION to 147 (Michaël Zasso) #61898 * (SEMVER-MAJOR) remove deprecated and unused isolate fields (Michaël Zasso) #60488 * (SEMVER-MAJOR) update NODE_MODULE_VERSION to 144 (Michaël Zasso) #60488 * (SEMVER-MAJOR) include `node_api_types.h` instead of `node_api.h` in `node.h` (Anna Henningsen) #60496 * (SEMVER-MAJOR) update NODE_MODULE_VERSION to 142 (Michaël Zasso) #60111 stream: * (SEMVER-MAJOR) promote DEP0201 to runtime deprecation (René) #62173 * (SEMVER-MAJOR) move _stream_* to end-of-life (Sebastian Beltran) #60657 * (SEMVER-MAJOR) readable read one buffer at a time (Robert Nagy) #60441 * (SEMVER-MAJOR) preserve AsyncLocalStorage on finished only when needed (avcribl) #59873 test: * (SEMVER-MAJOR) skip wasm allocation tests in workers (Michaël Zasso) #61898 * (SEMVER-MAJOR) update wpt Wasm jsapi expectations (Michaël Zasso) #61898 * (SEMVER-MAJOR) support presence of Temporal global (Michaël Zasso) #61898 * (SEMVER-MAJOR) add type tags to uses of v8::External (gahaas) #61898 * (SEMVER-MAJOR) fix test-linux-perf-logger for V8 14.3 (Michaël Zasso) #60488 tools: * (SEMVER-MAJOR) remove v8_initializers_slow workaround from v8.gyp (Michaël Zasso) #61898 * (SEMVER-MAJOR) add Rust args to `tools/make-v8.sh` (Richard Lau) #61898 * (SEMVER-MAJOR) update V8 gypfiles for 14.6 (Michaël Zasso) #61898 * (SEMVER-MAJOR) update V8 gypfiles for 14.5 (Michaël Zasso) #61898 * (SEMVER-MAJOR) update V8 gypfiles for 14.4 (Michaël Zasso) #61898 util: * (SEMVER-MAJOR) mark proxied objects as such when inspecting them (Ruben Bridgewater) #61029 * (SEMVER-MAJOR) reduce TextEncoder.encodeInto function size (Yagiz Nizipli) #60339 PR-URL: #62526

`processTypeScriptCode` does not produce source maps at all for type stripping. Given that the transform mode was removed, there is no need to keep the source map support around it. Signed-off-by: Chengzhong Wu <cwu631@bloomberg.net> PR-URL: #63738 Refs: #61803 Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

Node 26 removed the "transform" value (nodejs/node#61803); the getter returns "strip" by default or false under --no-strip-types. Code feature-detecting TypeScript support against Node 26 checks for "strip", so returning "transform" breaks strict comparisons.

… MCP negotiation test; provider-view cross-process coverage (integration) (#554) * fix(scripts): choose the TypeScript transform flag Node actually supports (Node 26 drops --experimental-transform-types) runScript spawned every plain .ts script under node --experimental-transform-types. Node 26 removed the flag (nodejs/node#61803) and rejects it as a bad option (exit code 9), so the Verify (Node 26) leg failed on every main push. typeScriptTransformFlags (core/runtime.ts) decides from process.allowedNodeEnvironmentFlags: the transform flag where the binary accepts it (Node 22, 24), nothing on Node 26, which strips types unflagged. Unit-tested against the flag sets of each release line. * chore: name #554 in the changeset * fix(scripts): name --strip-types on Node 26 so an inherited NODE_OPTIONS=--no-strip-types cannot switch TypeScript loading off Codex review on #554: with no command-line flag the child inherited the environment's --no-strip-types and failed on every typed .ts source. The helper now picks the first flag the binary accepts, strongest first: --experimental-transform-types (22, 24), then --strip-types (26). Covered by a script-dispatch test that sets the version-appropriate switch in NODE_OPTIONS and expects the source run to succeed regardless. * test(routes): prove the provider request view across built surfaces; fix framework-mode.md ordering (from #556) * fix(install): apply the operator .env layer before plugin modules evaluate and below manifest env defaults (#469) Two findings from the #538 self-review. Precedence: a host merges the stdio server's manifest `env` block into the child environment, so the shell could not tell a manifest default from a host export and reserved both — manifest env beat the file, contrary to the documented `manifest < .env < .env.local < process.env`. The emitted stdio entry now embeds the server's normalized `env` block as build-time literals and `applyOperatorEnv` takes it as `manifestEnv`: a present variable is reserved only when its value differs from the embedded default, so a passed-through default yields to the file while a host or operator export is kept. An operator export equal to the default is indistinguishable from the pass-through and yields too; a default carrying a path token never equals its expanded value and is always kept. Host manifests are unchanged. Import timing: the layer was a statement after the consumer imports, and ESM evaluates static imports first, so module-level `process.env` reads in hook handlers and CLI route/provider modules never saw the file. A dynamic `import()` after the statement does not help either — Rspack inlines a single-chunk bundle into one scope and places the dynamic target ahead of the static imports. The layer is now a generated virtual module (`agent-bundle/launch-env-layer`) that every stdio entry, hook wrapper, and artifact CLI bin imports first, with the server module, handler, routes, providers, and state definition as static imports after it; the build marks generated modules side-effectful so a consumer `"sideEffects": false` cannot drop the bare import. The MCP shell's `loadEntry` becomes a static import for the same reason, so the console guard now covers the factory call and the running server rather than the module's top-level evaluation. Tests build each shell through the real pipeline and run it under node with a `process.env` read at module top level: manifest-only key takes the file, host-exported key keeps the host value, absent key takes the file, `AGENT_BUNDLE_ENV_FILE=none` restores the previous behaviour. * chore: drop the tracked .superpowers scratch notes and ignore the folder * fix(mcp): install the stdout guard in the stdio entry's first import so module-scope writes never reach the protocol stream (#469) The env-precedence follow-up made the generated stdio entry import the server module statically so the operator .env layer lands by import order — but that put the module's top level ahead of the console guard that `runGeneratedStdioMcpEntry` installs in the shell body. A `console.log` or `process.stdout.write` at module scope in a consumer's server or tool module reached stdout, which carries JSON-RPC framing, contradicting the documented guarantee that redirection precedes the consumer module's evaluation. The stdio shell now imports a generated prelude (`agent-bundle/stdio-prelude`) as its first import: it calls `redirectConsoleToStderr` from `agent-bundle/mcp-entry`, then applies the operator .env layer with the server's manifest env defaults. Hook wrappers and the artifact CLI bin keep the env-only layer (`agent-bundle/launch-env-layer`) — they legitimately write stdout. The guard has one implementation: `redirectConsoleToStderr` returns the guard already installed (recognised by `process.stdout.write` still being its redirect) instead of stacking a second, which would capture the redirect as the original and restore stdout to stderr; the lifecycle adopts the prelude's guard and restores raw stdout from it before serving. Tests: a built stdio entry whose server module writes `console.log('hello')` and `process.stdout.write('raw\n')` at module scope, driven by a real stdio client through initialize, tools/list, and tools/call, asserts both land on stderr (fails on the previous code: stderr held only the factory-time line); the entry-shell unit tests pin the prelude as the stdio entry's first import and the env-only layer for hook wrappers and the CLI bin; the mcp-entry unit test pins guard adoption and re-install after restore. * fix(mcp): adopt the installed stdout guard regardless of write identity so a consumer wrapper cannot stack a second guard (#469) Adoption by identity (`process.stdout.write === redirectedWrite`) broke the moment a consumer module wrapped `process.stdout.write` at module scope: the lifecycle's `redirectConsoleToStderr()` saw a foreign function, installed a second guard with the wrapper recorded as the original, and restoring for the protocol stream handed stdout to the wrapper — which still forwarded to the first redirect, so every JSON-RPC frame left on stderr and the client hung in initialize. The rule is now: while a guard is installed, `redirectConsoleToStderr()` returns it whatever `process.stdout.write` has become; `restoreProtocolStdout()` restores the real original the guard owns, writes one stderr line if a module replaced the write in the meantime (the replacement is discarded — stdout is the protocol channel and wrapping it is unsupported), and clears the installed guard so a later call installs anew. Tests: the mcp-entry unit test wraps the redirect, adopts the same guard, restores to the real stdout, and installs fresh afterwards (fails on a677371 at the adoption step); the packed stdio test's server module now also wraps `process.stdout.write` at module scope and the real client still completes initialize, tools/list, and tools/call with the wrapper's output and the warning on stderr (hangs to timeout on a677371). * fix(mcp): make restoreProtocolStdout once-only so a stale or repeated restore cannot clobber a fresh guard (#469) Two holders of the same guard could restore twice: after the first restore and a fresh install, the stale restore overwrote the fresh redirect with the old original while `installedGuard` still named the fresh guard, so adoption returned a guard that was no longer installed. A plain double restore also emitted the foreign-wrapper warning twice. The guard now records that it has restored and returns immediately on later calls.

marco-ippolito added the semver-major PRs that contain breaking changes and should be released in the next major version. label Feb 13, 2026

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marco-ippolito force-pushed the rip-transform-type branch from 2ea1afe to c62af40 Compare February 13, 2026 16:59

ShogunPanda approved these changes Feb 17, 2026

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absidue mentioned this pull request Feb 19, 2026

feat: add support for --experimental-transform-types electron/electron#49711

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marco-ippolito force-pushed the rip-transform-type branch from c62af40 to 70303e1 Compare February 23, 2026 16:07

marco-ippolito force-pushed the rip-transform-type branch from 70303e1 to 50a77db Compare February 23, 2026 16:42

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lenovouser mentioned this pull request May 9, 2026

Implement erasable Enum Annotations microsoft/TypeScript#61414

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coderabbitai Bot mentioned this pull request May 9, 2026

Signup workflow jakala-na/next-hydra#54

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leonqadirie mentioned this pull request May 14, 2026

alchemy dev fails on Node 26: --experimental-transform-types was removed alchemy-run/alchemy#343

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legendecas mentioned this pull request Jun 3, 2026

lib: remove source map deadcode in type stripping #63738

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coderabbitai Bot mentioned this pull request Jun 13, 2026

Markdown-first CLI, local engines/mirror, HTML export, and Electron + React scaffold YellowKidokc/Forge-electron#4

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mcollina mentioned this pull request Jul 15, 2026

Expose the full Amaro loader API via 'node:module' #64518

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coderabbitai Bot mentioned this pull request Jul 17, 2026

Overnight integration #1: trusted-state (real kill-9) + effect-protocol + git-hardening + hermetic-rehearsal + durable effect-event store aumara-xyz/aukora#127

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cirospaciari mentioned this pull request Jul 25, 2026

node:module: stripTypeScriptTypes strip mode + StrippedTypeScript compile cache (+3 tests) oven-sh/bun#35517

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robobun mentioned this pull request Aug 6, 2026

process: report features.typescript as "strip" to match Node 26 oven-sh/bun#37014

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This was referenced Aug 6, 2026

Upgrade to Next.js 16.3, Instant Navigations, and landing Lighthouse wins TommyBez/skillsboard#93

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Add an async context data test for @fedify/express fedify-dev/fedify#985

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config loading breaks on node 26 with typescript 7 (stripTypeScriptTypes transform mode removed) expo/expo#48724

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expo config fails to load app.config.ts on node 26 (stripTypeScriptTypes transform mode removed) expo/expo#48725

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robobun mentioned this pull request Aug 13, 2026

node:module: implement stripTypeScriptTypes oven-sh/bun#32206

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expo-bot mentioned this pull request Aug 18, 2026

fix(require-utils): Fix Node 26 stripTypeScriptTypes fallback call expo/expo#48826

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coderabbitai Bot mentioned this pull request Aug 23, 2026

Add response-handling tests for @fedify/h3 fedify-dev/fedify#1007

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CrazyCoder mentioned this pull request Aug 27, 2026

Test scripts cannot run on Node 26: --experimental-transform-types was removed in v26.0.0 4fuu/pi-pwsh#8

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ScriptedAlchemy mentioned this pull request Sep 4, 2026

fix: Node 26 transform flag; operator .env precedence + import order; MCP negotiation test; provider-view cross-process coverage (integration) ScriptedAlchemy/agent-bundle#554

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module: remove --experimental-transform-types - #61803