Chris Tate
140990d257
A large program's hot code spans hundreds of 4 KiB pages, more than the instruction TLB holds. tsc-ts has 12 MB of code, and 90% of its main-thread samples at --checkers 1 fall in 274 distinct code pages. `scriptc build --large-pages` links the new runtime unit scr_text_pages.c, whose constructor moves the executable's code onto 2 MiB transparent huge pages before main. It copies the executable segment, from its first to its last 2 MiB boundary, into anonymous memory advised MADV_HUGEPAGE, makes the copy read-only and executable, and moves it over the original range with one mremap, so addresses and instructions stay the same. The move runs only on Linux, only when THP is "always" or "madvise", and only in executables. If a step fails, the code stays file-mapped. Like Node's --use-largepages, it is off by default: without the flag the unit is not linked, and executables are unchanged. The move costs about 3 ms per 10 MiB of code at startup, and all of the moved code stays resident as private memory. The flag is part of the executable cache key and the runtime-pack selection, and is refused for non-executable output, like --detached-exit.
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