Just

Zero config TypeScript build and development toolkit.

Features

• Fast SWC compiler
• TypeScript type check support
• Live reload support
• .env file support
• Path alias support
• Typescript script runner
• REPL support

Install

# Locally in your project.
npm install -D @sonnyt/just

# Or globally
npm install -g @sonnyt/just

Usage

To start a dev server in the root of your project just (😉) run:

just dev

To build:

just build

Commands

Build

just build [options] [files]

Compiles the application for production deployment.

Arguments

• files - glob file path to compile. If not present, includes from config.json is used.

Options

Option	Default	Description
--transpile-only	off	disables type checking
--out-dir <outDir>	compilerOptions.outDir	output folder for all emitted files
--no-color	off	disables output color
--debug	false	enables debug logging
-c, --config <config>	default	path to typescript configuration file

Dev

just dev [options] [entry]

Starts the application in development mode. Watches for any file changes and live reloads the server.

Arguments

• entry - server entry path to start. If not present, main from package.json is used.

Options

Option	Default	Description
-p, --port <port>	null	server port used in process.env.PORT
--type-check	false	enables type checking
--no-color	off	disables output color
--debug	false	enables debug logging
-c, --config <config>	default	path to typescript configuration file

Run

just run [options] <command> [args...]

Runs .ts file scripts.

Arguments

• <command> - script/command to run.
• [args...] - arguments passed to the script/command.

Options

Option	Default	Description
--no-color	off	disables output color
--debug	false	enables debug logging
-c, --config <config>	default	path to typescript configuration file

Programmatic

You can require Just runner programmatically two ways:

Import Just as early as possible in your application code.

require('@sonnyt/just/register');

Or you can use the --require (-r) command line option to preload Just. By doing this, you do not need to require and load Just in your application code.

node -r @sonnyt/just/register myscript.ts

Please note that runner does not support type checking.

Default Config File

Just automatically finds and loads tsconfig.json or jsconfig.json. By default, this search is performed relative to the entrypoint script. If neither file is found nor the file is not provided as an argument. Just falls back to using default settings shown below.

{
  "compilerOptions": {
    "module": "CommonJS",
    "target": "ES2021",
    "moduleResolution": "Node",
    "inlineSourceMap": true,
    "strict": true,
    "baseUrl": "./",
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "importHelpers": true,
    "outDir": "dist",
    "paths": {}
  },
  "include": [
    "./"
  ],
  "exclude": [
    "node_modules"
  ]
}

Environment Variables

When using the dev or run commands. Just automatically finds and loads environment variables from a .env file into process.env. By default, this search is performed relative to the entrypoint script.

Path Alias

Based on the paths configuration, Just replaces all alias paths with relative paths after typescript compilation.

FAQ

Does Just work with ES Modules?

Currently, Just only supports building ES Module files.

What's the REPL use case?

Just REPL enables you to execute TypeScript files on Node.js directly without precompiling. It serves as a replacement for ts-node.

Does Just compile alias paths?

Out of the box, Just supports build and runtime path aliases. All output file alias imports are replaced with relative paths.

What happens to my non-JavaScript/TypeScript files?

If your source directory includes non-compilable files (i.e., JSON, SVG, etc.), Just automatically copies them into your output directory.

How can I help?

If you would like to contribute, please see the issues labeled as help-wanted.

Roadmap

• Build watch option #7
• Init option - copy over the default config file to the working directory #5
• TypeScript ESLint support #6
• Prettier support
• REPL ES module support
• jsconfig.json support
• .swcrc support