Install & run

Langoost is in active development. Today you build it from source with the Go toolchain; prebuilt binaries are planned for a later release.

Prerequisites

• Go 1.21 or newer

Build from source

$ git clone <langoost-repo>
$ cd langoost
$ go build -o langoost .

This produces a single langoost binary in the current directory.

During development you can skip the build step and run directly with go run . run script.goost.

Your first script

Create hello.goost:

let name: string = "world"
print("Hello, " + name + "!")

Run it:

$ ./langoost run hello.goost
Hello, world!

Projects & building

For anything beyond a single script, use a project — a directory with a src/ folder whose src/main.goost is the entry point. langoost build compiles it into a self-contained build/ directory:

myapp/
├── src/
│   └── main.goost      ← entry point
└── build/              ← created by `langoost build`
    ├── myapp           ← standalone native binary (pure-Go)
    ├── run.sh          ← loads .env, then runs the binary
    └── .env            ← default config (created once, never overwritten)

$ ./langoost build ./myapp
$ ./myapp/build/run.sh

Deployment is a copy: ship the build/ directory to a server and run run.sh — no Go toolchain and no Langoost install required. To make a one-off binary from a single file instead, use langoost compile. See the CLI reference for cross-compilation and flags.

The REPL

Start an interactive session to experiment line by line:

$ ./langoost repl
> let x = 21
> print(x * 2)
42

Press Ctrl+D to exit.

Server mode

Langoost can run as a persistent execution server — the model it’s designed for. The process stays warm and serves requests with no cold start. It binds loopback by default:

$ ./langoost server

It exposes an HTTP API (POST /execute, GET /health, DELETE /cache); see the execution server guide for the endpoints and auth. To build an HTTP API directly from a script instead, see the HTTP server guide.

Inspect the bytecode

Curious what the compiler produces? Disassemble any script:

$ ./langoost disasm hello.goost

Next: take the language tour.