Promise Lang

Under active development

A statically-typed language designed for AI-agent efficiency.

Explicit ownership (like Rust), structured concurrency (like Go), algebraic error handling, generics, and exhaustive pattern matching — with zero hidden effects. Reading a single .pr file tells you exactly what it does. Native LLVM compilation to Linux, macOS, Windows, and WASM.

type Circle {
  f64 radius;
  get area f64 => 3.14159 * this.radius * this.radius;
}

main() {
  c := Circle(radius: 5.0);
  print_line("Area: {c.area}");
}

🚧 Launching soon. The Promise compiler and toolchain are not public yet. The Promise repository is still private and will go live with its first release soon.

Want early access? Email early@promise-lang.org to request early access or to be notified the moment the language repository goes public.

GitHub Language Guide VS Code Marketplace Open VSX

VS Code extension source: github.com/promise-language/vscode-promise