In JavaScript, `ReleaseEmitter = EventEmitter` over `const EventEmitter =
require("events")` was refused with SC1090 ("a runtime-provided class value
as an untyped value"), and `class Channel extends require("events")` failed
on the require call as a value. Bundled npm code does both, for example a
small semaphore that aliases EventEmitter and constructs its release channel
through the alias.
- The events module binding and the EventEmitter or stream class itself
turn untyped as the runtime's untyped constructor that constructor
functions already use (scr_dyn_builtin_class.c). `new` through it builds
an emitter object with Node's listener API, and `===` against the class
compares identity.
- `x instanceof EventEmitter` on an untyped value also recognizes a boxed
compiled emitter (an instance of a program class extending EventEmitter),
which the prototype test alone answered false for. The same holds through
an untyped binding narrowed to the class.
- `class X extends require("events")` extends the runtime emitter, as
through a require binding.
- A typed array of the class built from such values (`[EventEmitter]`) is
refused with SC1090 rather than failing its class check at run time.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A bundle that embeds fs-extra (build-utils does) compiled the package's
own JavaScript, whose computed export table and graceful-fs internals the
static model cannot follow. A __commonJS chunk whose key names a shimmed
package's main file at a supported version now requires the shim
instead, through a forwarder declaration beside the bundle: the checker
follows it to the shim (a package's JavaScript cannot load TypeScript
sources directly), and module resolution answers the shim for its path.
The package's other chunks are no longer reached. Calls through such a
require of a TypeScript module lower when the export never reads `this`
(require() answers the module's namespace).
package-shim-guard.test.ts compiles every registered shim module under
both type worlds and fails on any lowering diagnostic or fence inside the
shims, reached or not.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A bundled package's error class defined inside an __esm initializer
(`NowBuildError = class extends Error { … }`) now hoists to a declaration
like the classes over builtin module members, so a program class can
extend it and `new` and `instanceof` work against both. Reading a standard
global constructor the bundle never rebinds runs no code. References in
esbuild's `0 && (module.exports = { … })` annotation for Node's CommonJS
lexer never run and no longer block the move.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A class a bundled ES module's __esm initializer stores into a module
binding (`Multi = class extends import_stream.Readable { … }`) becomes a
class declaration at the same text position: the initializer's body splits
around it into run-once pieces, so a class over a runtime-provided base no
longer has to exist as a stored class value. Only definitions whose
evaluation runs no code (no static fields, static blocks or computed names;
heritage absent, a builtin module member, or a hoisted class), declared
once, assigned only there and read only inside functions after the
assignment move.
npm selection now also scans the program modules a literal import()
reaches, with their static graphs: a workspace package loaded on demand
had its npm dependencies refused as "not part of the compiled module
graph".
`new import_x.C()` respelled `new require("x").C()`, which constructs the
require call; the interop binding now becomes `(require("x"))` there.
util.inherits onto a runtime-provided class (stream.Readable, the from2
and multistream shape) fences where it is written instead of failing in
Node's argument validation at run time.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
isarray, safe-buffer, process-nextick-args, inherits and util-deprecate
evaluate to a Node builtin on Node 24 at their checked major versions, so
a require of one compiles as that builtin expression at the require's
position: from an opted-in package's files (the installed version where
Node's resolution finds it), from the program's own CommonJS files, and
through an esbuild __commonJS chunk whose pnpm path key names the package
and its version. The package's files never join the program.
readable-stream 2.x and 4.x compile as node:stream, the package's own
READABLE_STREAM=disable behavior (a documented divergence). A use of the
entry's export picks the builtin module (member reads of the carried
classes) or stream.Readable (value uses); a mixture keeps the package.
3.x stays as is: its disable branch throws on Node 24.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A CommonJS module whose export object is one of its own top-level
functions (semver 5/6's `exports = module.exports = SemVer`) reaches
its members through that function after the statement: member reads
and writes through module.exports (and, after the rebinding, every
`exports` reference) become members of the function, the expando form
both resolvers model, and the rebinding itself drops. Constructor
functions exported whole with members attached afterwards no longer
lose those members at runtime.
Replacing module.exports or rebinding exports inside a branch (an
environment-dependent export object, readable-stream 2.x) now names the
construct instead of the generic assignment fence, and a required
builtin module object is truthy in the LLVM backend.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A call through a bundled ES module's namespace (`ns.fn()`, `(ns.fn)()`,
a tagged template) passes the namespace as `this`. Node's namespace is
the __toCommonJS object (`__esModule` first and non-enumerable,
non-configurable getters); the lowered object of getters differs. The
namespace lowers only when every such call targets a top-level function,
never reassigned, that reads no `this` (an arrow inside it included);
otherwise the package stays refused.
- A star re-export of a lazily initialized module into the bundle's
exports (__reExport(main, (init_x(), __toCommonJS(x_exports))))
initializes the module at the statement and adds its names to the
export table after the explicit ones, without default.
- The rewrite keeps the original's lexer answer whenever its export
table holds accessors (Node's lexer stops at the first one).
- An npm alias directory of a selected package ("x-updated":
"npm:x@6.3.0") resolves to that package's JavaScript in both resolvers.
- "use strict" code may read arguments in functions with parameters.
- A comma expression ending in null/undefined coerces its result.
- A void conditional return lowers as control flow.
- A detached method of a local class drops its empty capture list.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A loader `L = () => M ??= NS` over a lazily initialized module's
namespace (optionally through __toESM) is respelled at every `L().name`
as the module's initializer call followed by the export's live read;
loaders whose result escapes as a value stay refused. The canonical
export table keeps a getter it cannot chase as a live accessor, so a
lazy re-export still initializes its module at the first read. An
ES-module importer copies those accessors once when it links the
CommonJS module, in the lexer's order, exactly like Node's loader;
require() keeps reading them live.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
An untyped package another package's JavaScript imports is selected
whether resolution answers no declarations or its JavaScript. A
DefinitelyTyped twin qualifies by identity (@types/<mangled name>):
the declarations only check the program, and the JavaScript compiles
with its inferred surface, so a twin that disagrees with the shipped
JavaScript fails the build at the use rather than compiling against it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
An __esm initializer becomes a run-once closure over its body in the
bundle's own scope. Interop bindings it assigns once from require()
become that require at the assignment, with their member reads respelled
as reads of the required module; a namespace read only through members
becomes an object literal of getters over the module's live bindings.
Asynchronous initializers, initializer results, and namespaces kept as
values (a memoized lazy loader) stay refused with a message naming them.
The default selection now also compiles a package typed by a
DefinitelyTyped twin that describes its installed release (same major,
or major.minor below 1.0), and untyped dependencies of compiled
packages. A twin for another release is refused with both versions.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Interop the rewrite cannot finish now refuses its package only when the
compiled program can load that file: the module order closed over every
literal require() and import() and, in package JavaScript, every import
and export declaration (a computed specifier keeps every file loadable).
A package reached through a leaf subpath and types from its main entry
stays static. Auto mode also no longer refuses a whitespace/syntax
minified bundle whose interop helpers keep their names: the recognizers
judge it instead.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Unit tests run each split bundle against its original under Node and
pin the refusal reasons; npm-static tests compile the new cases and
compare them with Node byte for byte.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
scriptc's resolver and tsgo must answer one runtime file for every
opted-in npm edge; four disagreements left the file outside tsgo's
program (SC2013 "did not join the type-checked program") for express,
axios, body-parser, execa, fast-glob, globby, knex, uuid and tldts:
- uuid: the node-condition hoist re-added the inner "types" key after
the claims were deleted; tsgo then took the browser build. Delete the
claims after the hoist.
- tldts: tsgo's TypeScript-first lookup took the shipped root index.ts
over "main". The fs shadow hides installed TypeScript sources of
opted-in packages that have no same-stem runtime JavaScript.
- express: tsgo redirected same-version duplicate installs to one copy,
either dropping a copy or merging two Node module instances into one.
The shadow serves opted-in package.json files without "version".
- deep chains (get-intrinsic, dunder-proto, run-parallel, reusify,
supports-color): maxNodeModuleJsDepth charges every node_modules hop.
The program-root fixpoint also roots opted-in bare edges' runtime
files that the program is missing.
All changes are gated on --npm-static being active.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A require cycle was always refused (SC1016). Node answers a require of a
module that is still evaluating with its exports as they stand, while the
compiled bindings alias the final declarations; the two agree when every
module of the cycle assigns all of its exports before its first statement
that can run another module's code, every other use of its export object
is a plain member read, and no module's top-level code can reach its
binding of another member. Each module then initializes exactly as it
would outside the cycle. This admits semver's comparator/range cycle
("hoisted class for cyclic dependency"); other cycles keep SC1016 with a
reason naming the offending statement.
The require reachability scan no longer treats a declaration's own name
as a read (esbuild's `var X = class {...}` before its requires), treats a
plain write of an export member as running only a setter published for it
(on-finished's `module.exports.isFinished = isFinished`), and keeps the
conservative scan for writes of __proto__, __esModule and members of a
replaced export object.
Evidence: corpus 6145 (the cycle), 6142 gains the esbuild layout; the
npm-static harness compiles the published fs.realpath@1.0.0,
on-finished@2.4.1 (with ee-first@1.1.1) and statuses@2.0.1 statically;
program.test.ts pins the TDZ analysis through var bindings plus the cycle
admission and refusals. Preflight/order baselines recorded for the new
fixtures; a full re-record changed no other fixture. Dependencies and
limitations docs describe the supported require forms.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- A package typed only by an @types twin was judged under the twin's name
and refused with "its import resolves to '@types/x/index.d.ts', not to
runtime JavaScript". Selection now resolves the runtime package, and the
refusal names it with the --npm-static option that compiles it anyway.
- Refusals the declaration and shipped-JS heuristics make carry the same
remedy as a diagnostic hint; a dependency of a named package suggests
the transitive form.
- `--npm-static=pkg...` (and `"pkg..."` in a library profile) selects the
package and every package its files import, nested require() calls
included, without the eligibility heuristics.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Node runs TypeScript with verbatimModuleSyntax semantics: `import type` and
`export type … from` vanish, while `import { type A }` and
`export { type A } from` keep an empty clause and still load their module.
- Package selection skipped nothing: `import type { X } from "type-fest"`
selected type-fest and failed with SC2013, and type imports pulled whole
packages into the compile. Erased edges no longer select packages.
- Files reached only through erased edges are no longer program modules,
so their imports (a `node:vm` import, say) no longer fence the build.
- Inline type-only clauses are real module edges again (their modules'
side effects ran under Node but not in the binary); a cycle closed by
one binds nothing and is admitted like a side-effect import.
- Interfaces, type aliases and type literals from an installed package's
declarations map structurally, so values the program builds with a
type-only package's types compile.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A package function that destructures its options object, such as
makeClass({ Base, name }), now specializes per call site like positional
parameters: each destructured name binds the static type of the matching
property, so a class passed as { Base } keeps its static type and
class extends Base builds a constructible subclass.
Fixes#938
Co-authored-by: phall <25888173+phall1@users.noreply.github.com>
`value.valueOf()` on a dynamic receiver was refused at compile time, a
class's own toString was not reached by `value.toString()`, and classes
could not declare a `[Symbol.toPrimitive]` method.
- `value.valueOf()` lowers to dyn.valueOf, which answers each kind's own
valueOf: a primitive itself, a Date its time value, an object with a
valueOf member that member's result, and any other object itself. A
null-prototype dictionary throws "<spelling> is not a function", and
null and undefined throw Node's property-read TypeError.
- When a boxed class declares valueOf or toString, `value.valueOf()` and
`value.toString(argument)` call the class's method for its instances
and keep the runtime call for every other value.
- Classes can declare `[Symbol.toPrimitive](hint)`. The dynamic
conversions call it with "default" for `+` and `==`, "number" for the
numeric operators and conversions, and "string" for template literals,
String() and property keys, and throw Node's TypeError when it returns
an object.
A static method that a function-local JavaScript class defines at
runtime and a program class inherits (Animal.extend("Dog")) is now
called directly with this bound to the receiver class when it captures
nothing from the factory's scope, so the subclass it builds has a static
base and constructs like Node.
Fixes#938
Co-authored-by: phall <25888173+phall1@users.noreply.github.com>
npm-static.test.ts ran whole on one shard as an isolated suite: 406 s plain and
519 s sanitized in the cost table, and 672 s on san 2/20 in run 38835202089,
the second-longest job of that run.
skipUnownedTest (tests/harness/shard.ts), called from the suite's beforeEach,
balances the suite's tests across the shards of SCRIPTC_TEST_SHARD by their
measured milliseconds (tests/harness/npm-static-costs.json; an unmeasured test
weighs as much as the median) and skips the tests this shard does not own.
Repeated test.each titles get an occurrence suffix as their key. Without a
shard spec every test runs.
The CI plan runs the suite on every shard in its own vitest process
(caseShardedSideFiles) instead of on one owner. At 20 shards the largest
shares are 113 and 106 s plain and 181 and 137 s sanitized (the two published
Effect generator tests), and about 10 s elsewhere, plus about 11 s per shard to
collect the file. scripts/ci-test-costs.mjs also refreshes the per-test table
and drops side-queue files that no longer run whole.
- Enforce oxlint and oxfmt for owned JavaScript and TypeScript with independent CI checks.
- Preserve compiler import boundaries and protected fixtures while cleaning up lint findings.
- Standardize source formatting and validate import, fixture, and embedded-source protections.
* Expand static compilation for common Effect 4 patterns
* Run every Effect 4 fixture slice in CI
* Preserve existing corpus behavior across Effect 4 lowering
* Preserve Effect platform callbacks and native stream state
* Record new corpus baselines and retain child stdin refusals
* Retire the obsolete stateful regex diagnostic
* Preserve promise reference count layout for cycle collection
* Expand static Effect support across common APIs
* Preserve compiler parity across expanded Effect patterns
* Fix compiler regressions exposed by Effect coverage
* Bound shared type conversion traversal
* Clarify conversion contracts and tidy fixtures
* Run every Effect fixture in CI shards
* Preserve inferred array assignments in concurrent Effect programs
* Record inferred array fixture compiler ordering
- Run published three.js vector, matrix, and quaternion operations natively and as Wasm without a JavaScript engine.
- Preserve shared class prototype data and JavaScript overload arguments.
- Support Math function values and distinct npm import and require entries.
- Remove C emission, debugging options, and automatic backend fallback.
- Complete LLVM lowering and native bootstrap coverage across supported targets.
- Link executables and libraries with precompiled C runtime packs, including iOS and Android.
- Carry BigInts, Sets, and regular expressions through checked native storage without a JavaScript engine.
- Preserve dictionary aliases, spreads, frozen metadata, and fluent initialization helpers.
- Collect checked object and closure cycles while preserving live references.
- Preserve async factory results and mixed table layouts through inference and destructuring.
- Support checked Map and Object.fromEntries construction with native weak collections.
- Keep native weak-key lifetimes and engine-backed collection identities intact.
- Support stored builtin helpers, typed rest callbacks, and shared FileHandle values.
- Preserve async results, specialized function bodies, and checked class receivers.
- Compile live export dictionaries and keep native property names distinct.
- Preserve unbound class methods, call-time receivers, and bound callback arguments.
- Keep native factory results, fallback functions, and mutable JavaScript renderer state intact.
- Support live Error.cause assignment, deletion, and property descriptors across aliases.
- Compile zero-argument callback fields and derived arrow replacements using their declared nullable type.
- Preserve callback captures, identity, and null resets in native class storage.
- Carry declaration-backed string, number, and boolean method results into static JavaScript compilation.
- Match named class re-exports to their implementations while preserving self types and rejecting ambiguous aliases.
- Keep fields, accessor parameters, and return values inferred as undefined in native checked storage.
- Preserve virtual dispatch for overridden methods in JavaScript packages.
- Route assignments through class accessors without creating shadow fields.
- Statically resolve stable let/var createRequire bindings while rejecting mutation, escape, and early use.
- Compile node:console output methods to native process streams and retain explicit custom Console refusals.
- Extend native FFI with additional scalar widths and writable byte spans.
- Compile stored text codecs and supported bundled module patterns without a JavaScript engine.
- Document supported limits.
Chris Tate