Gizlang

TypeScript syntax. Native speed. One toolchain.

Gizlang reads like TypeScript and compiles to native code through LLVM. The compiler, the standard library, the test runner, the formatter, the language server and live code swap are one command: gizlang.

gizlangRun

type Item = { name: string; price: i64; };

function total(items: Vec<Item>): i64 {
    let sum = 0;
    for (const item of items) { sum += item.price; }
    return sum;
}
function main(): void {
    const cart = [Item("tea", 4), Item("cake", 7)];
    print("Total: " + string(total(cart)));
}

text

Total: 11

Why Gizlang

Native speed
On LangArena's 50 realistic programs, our run scores 90.7. Rust scores 90.6 and C 90.2 on the same machine.
No garbage collector
Values are reference-counted and copied only when shared. Memory goes back when its last owner goes. There are no collection pauses.
Errors you cannot ignore
There are no exceptions. A function that can fail returns a Result. The compiler refuses a match that forgets a case.
Markup in the language
TSX-style markup in ordinary .giz files compiles to typed, escaped HTML. Components are typed functions.
Live code swap
giz live replaces the code of a running program and keeps its state. An edit to an app of 800 lines is live in 53 ms.
Explicit capabilities
Files, network and processes come from the System value that main receives. A function that has no System cannot reach them.
Cheap tasks
One million switches between hot tasks take 18 ms. Channels connect them.
Made for AI agents
giz check --json, giz outline and giz capabilities give structured answers. Every docs page is Markdown at /llms.txt.

One command for the whole job

Job	Command
Run a file	`giz main.giz`
Check types, without a run	`giz check main.giz`
Test	`giz test`
Format	`giz fmt`
Build a native executable	`giz build main.giz -o app`
Build WebAssembly	`giz build --wasm main.giz -o app.wasm`
Change a running program	`giz live main.giz`
Read the docs of a module	`giz doc Json`
Debug	`giz build --debug main.giz -o app`, then gdb, lldb or VS Code
Editor support	`giz lsp` and the VS Code extension
Interactive session	`giz repl`

The command line guide shows each one.

Editor and debugger

The VS Code extension shows what the compiler says as you type: errors with their fixes, completion, hover, rename, formatting and inlay hints. Its Test Explorer runs the tests of each file. Press F5 to debug: breakpoints in .giz files, stepping by line, the call stack and the variables by their Gizlang names. gdb and lldb debug the same builds from a terminal (Debugging).

The standard library

37 modules ship compiled in the toolchain. A program imports them as gizlang:NAME, with no package install.

Area	Modules
Core and data	`core`, `collections`, `text`, `unicode`, `regex`, `json`, `csv`, `math`, `random`, `time`
Web and network	`http`, `html`, `tls`, `acme`, `crypto`, `security`, `compress`
Data stores	`sqlite`, `postgres`, `odbc`, `journal`
Concurrency and live code	`task`, `live`, `memory`, `metrics`
System	`system`, `path`, `native`, `runtime`
Compute	`tensor`, `nn`, `grad`, `gpu`, `kernel`
JavaScript interop	`js`
Tests	`test`

Learn it

Try it in the browser. The Playground runs any example on this site.
Install it. One signed installer for Linux x86-64.
Take the tour. The language guide is for developers who know TypeScript, JavaScript or Go.