Chris Tate
d9481023c3
A profile annotates a function only while its control flow hashes as it did when the profile was collected, so compiler and source changes leave the changed functions without counts. A --profile-use build now reads a block-count file beside the profile (app.blocks beside app.profdata). Right after the annotation before inlining, the helper aligns each uncounted function's blocks with its recorded blocks by label kind and successor count. Paired blocks take their recorded counts and their edges the recorded edge counts, by target or, between targets whose labels changed, by position. LLVM's flow inference fills in the rest, avoiding the edges the function's own llvm.expect weights make unlikely. The helper then sets the entry count, branch weights and hot or cold attribute as the profile annotation does. SCRIPTC_RECORD_PROFILE_BLOCKS names the file a --profile-use build writes for the functions its profile annotates; such a build reuses no cached artifacts. The block file keys every cache, the build report counts the functions it annotated, and the staleness warning counts only the functions left without counts. A single-module build with a context-sensitive profile no longer counts annotated, mismatched and missing functions a second time after inlining. scripts/refresh-cli-profile.mjs records the file in the second phase and build-native-cli.mts reads it beside the profile.
scriptc
Compile TypeScript and JavaScript to native executables or WASI WebAssembly modules that run without Node.js installed.
$ cat fib.ts
function fib(n: number): number {
return n < 2 ? n : fib(n - 1) + fib(n - 2);
}
console.log(fib(30));
$ scriptc run fib.ts
832040
$ scriptc build fib.ts -o fib >/dev/null && ./fib
832040
scriptc compiles the same TypeScript you run on Node.js, type-checked by the TypeScript compiler. npm packages your program imports compile along with it. Code scriptc can't compile fails the build with an error code and, where available, a rewrite hint.
scriptc is experimental. See the limitations and the Node.js compatibility reference.
Install
$ npm install -g scriptc
npm installs the native compiler for your platform (macOS, Linux, or Windows). Node.js 24 or later is needed to install it and to run WASI modules with scriptc run; compiling and running executables doesn't need Node.js.
Building executables needs a linker and the platform SDK or sysroot, such as the Xcode Command Line Tools on macOS. Set SCRIPTC_LINKER to choose the linker driver. --emit=ir|llvm|asm|obj needs no external tools. See the quickstart for details.
Commands
scriptc build <file.ts>: compile to a native executable or another artifact selected with--emit.scriptc run <file.ts>: compile and run.scriptc coverage <file.ts>: report what compiles, and explain what doesn't.scriptc build --lib --profile <profile.json>: compile a static library, or a Wasm reactor onwasm32-wasi.
See the CLI reference for every option.
Cross-compilation and WebAssembly
Set SCRIPTC_TARGET to build for another platform, for example SCRIPTC_TARGET=aarch64-linux-gnu.2.36 or SCRIPTC_TARGET=wasm32-wasi. Install the matching @scriptc/runtime-<target> package in your project, at the same version as scriptc --version, or set SCRIPTC_RUNTIME_PACK to a runtime pack directory. See platform support and WebAssembly modules.
Native code
Call C functions by declaring their signatures in TypeScript and binding them to C symbols in a manifest passed with --ffi <manifest.json>. See the Native FFI guide.
Build cache
Builds reuse a bounded persistent cache. Set SCRIPTC_NO_CACHE=1 to bypass it or SCRIPTC_CACHE_DIR to choose its location.
Docs: scriptc.dev