mxscript

README

MX Script

A modern, open-source scripting language for building web apps and APIs. One file. Zero boilerplate. Run with mx run app.mx.

Founded and developed by Jassim Alkharafi.

server {
  port: 8080
}

let users = [
  { id: 1, name: "Jassim Alkharafi", role: "Founder" }
]

route GET /users {
  return json(users)
}

route GET /users/:id {
  let id = num(request.params.id)
  let user = find(users, fn(u) { return u.id == id })
  if (user == null) {
    return status(404, { error: "not found" })
  }
  return json(user)
}

That's it. No framework imports. No middleware setup. mx run app.mx and you have a JSON API on localhost:8080.

---

Why MX Script?

Most languages make you choose: ergonomics or speed. JavaScript is fast to write but you assemble a framework, a runtime, a build tool, and a deploy story before you ship anything. Go is fast and simple but the syntax for a JSON API is still a hundred lines.

MX Script is opinionated: the language is the framework. Routes, JSON, middleware, env vars, and AI calls are all first-class. The interpreter is a single Go binary with zero runtime dependencies.

• Single-file apps. No package.json, no Cargo.toml, no go.mod from your perspective.
• HTTP server, JSON parsing, env vars, fetch, and AI built into the language.
• Clean syntax. route GET /users { ... } reads like English.
• One binary. No virtual machine, no GC tuning, no node_modules.
• MIT licensed. Built in the open. Pull requests welcome.

---

Install

Option 1 — pre-built binary (coming soon)

Download from the releases page and put mx on your $PATH.

Option 2 — build from source

Requires Go 1.21+.

git clone https://github.com/jlkdevelop/mxscript.git
cd mxscript
go build -o mx .
./mx version

Option 3 — go install

go install github.com/jlkdevelop/mxscript@latest

The binary is named mxscript after go install. Rename or alias it to mx:

mv $(go env GOPATH)/bin/mxscript $(go env GOPATH)/bin/mx

---

Quickstart

mx init my-api
cd my-api
mx run app.mx

Then in another terminal:

curl http://localhost:8080/
curl http://localhost:8080/hello/Jassim

---

CLI

mx run <file.mx>               # run an MX Script program
mx run <file.mx> --port 3000   # override the server port
mx run <file.mx> --watch       # restart on file changes (hot reload)
mx run <file.mx> --debug       # print tokens and AST
mx init [name]                 # scaffold a new project
mx build <file.mx>             # parse & validate without running
mx repl                        # interactive REPL
mx version                     # print version
mx help                        # show help

---

Language tour

Variables

let name = "Jassim"
let age = 30
let active = true
let scores = [10, 20, 30]
let user = { id: 1, name: "Ada" }

// String interpolation
print("Hello, ${name}! Score sum: ${scores[0] + scores[1] + scores[2]}")

// Optional chaining + nullish coalescing
let city = user?.profile?.city ?? "unknown"

Functions

fn greet(name) {
  return "Hello, " + name
}

print(greet("world"))

Anonymous functions:

let doubled = map([1, 2, 3], fn(n) { return n * 2 })

Control flow

if (age >= 18) {
  print("adult")
} else {
  print("minor")
}

loop scores as s {
  print(s)
}

loop 5 as i {
  print(i)
}

let n = 0
while (n < 100) {
  n = n + 1
  if (n == 50) { break }
}

HTTP routes

route GET /             { return text("hello") }
route GET /users/:id    { return json({ id: request.params.id }) }
route POST /users       { return status(201, request.body) }
route DELETE /users/:id { return json({ deleted: true }) }

Middleware

middleware auth {
  if (request.headers["authorization"] != "Bearer secret") {
    return status(401, { error: "unauthorized" })
  }
}

route POST /admin {
  use auth
  return json({ ok: true })
}

Built-in functions

Category	Functions
Output	print, println
HTTP	json, text, html, status, redirect, fetch
Env	env(name)
String	len, upper, lower, split, trim, contains, replace, starts_with, ends_with
Array	push, pop, map, filter, find, join, reverse, range
Math	round, floor, ceil, abs, min, max, random
Types	typeof, isString, isNumber, isBool, isNull, isArray, isObject
JSON	json_parse, json_stringify
File I/O	read_file, write_file, file_exists, list_files, delete_file
Crypto	hash_sha256, base64_encode, base64_decode, uuid
Time	now(), now_iso(), sleep(ms)
AI	ai.complete(prompt), ai.embed(text)

See docs/api.md for the full reference.

AI built-ins

route POST /summarise {
  let summary = ai.complete("Summarise: " + request.body.text)
  return json({ summary: summary })
}

ai.complete reads OPENAI_API_KEY from the environment.

Error handling

try {
  let data = json_parse(request.body.payload)
  return json(data)
} catch (e) {
  return status(400, { error: e.message })
}

---

Project structure

mxscript/
├── main.go                 # CLI entry point
├── lexer/lexer.go          # tokenizer
├── parser/
│   ├── ast.go              # AST node types
│   └── parser.go           # recursive-descent parser
├── interpreter/
│   ├── interpreter.go      # tree-walking interpreter + HTTP server
│   ├── builtins.go         # standard library
│   └── parse_helper.go     # bridge for `import "./file.mx"`
├── examples/               # sample .mx programs
└── docs/                   # full language reference

---

Roadmap

See ROADMAP.md. Highlights:

• Lexer, parser, interpreter
• HTTP routes (GET / POST / PUT / DELETE / PATCH)
• request.body, request.params, request.headers, request.query
• Middleware via use
• Control flow (if, else, loop ... as)
• try / catch
• Standard library (string, array, math, JSON, types)
• ai.complete / ai.embed
• CLI: --port, --watch, --debug, mx init, mx build
• Local imports: import "./utils.mx"
• Pre-built binary releases for macOS / Linux / Windows
• Package registry (mx install pkg)
• WebSocket routes
• Built-in SQLite driver
• LSP for editor support

---

Contributing

MX Script is open source under the MIT license. Pull requests, issues, and discussions are welcome.

See CONTRIBUTING.md for the full workflow. The TL;DR:

git clone https://github.com/jlkdevelop/mxscript.git
cd mxscript
go build -o mx .
go test ./...
./mx run examples/app.mx

---

License

MIT © Jassim Alkharafi

---

Credits

MX Script was created by Jassim Alkharafi (founder & lead developer). If MX Script is useful to you, a ⭐ on GitHub goes a long way.

Documentation

Overview

main is the MX Script command-line entry point. It provides:

mx run app.mx [--port N] [--watch] [--debug]
mx init [name]
mx build app.mx
mx version
mx help

The CLI is intentionally tiny — every feature delegates to one of the language packages (lexer / parser / interpreter).