swig

Swig is a simple CLI tool for automating dev workflows via compositions of series and parallel tasks.

Write simple javascript or typescript functions and easily execute them in a shell in your project's root directory.

Fast. Simple. Convenient.

Pre-requisites

Node.js >= 16 (version 20 is recommended)

Why Swig Instead of Gulp?

Why recreate the "series", "parallel" and "task runner" functionality that Gulp already has? Gulp is great, but I wanted to be able to customize how it works, strip out all the noise and add the ability to use a variety of javascript/typescript flavors with little or no extra setup required.

Typescript Quick Start

Swig does not require typescript, but it is the recommended approach. For instructions on quickly setting up a new project that uses swig with typescript, see Swig Typescript Quick Start (or simply run npx swig-cli-init@latest in your target directory).

For general getting started steps, continue below.

Getting Started

• (Optional) Install swig-cli globally for convenient shortened commands and much faster task execution (no initial delay from npm/npx):

  # With npm:
  npm i -g swig-cli@latest
  
  # OR with volta:
  volta install swig-cli

• Install swig-cli package as a dev dependency so you can import series and parallel in your swigfile:

  npm i -D swig-cli

• Create a swigfile in the root of your project, such as swigfile.js (see Swigfile Syntax Options Matrix)

• Add some tasks to your swigfile (see Series, Parallel and Composability Example)

• List detected tasks from your swigfile (exported functions):

  # Global swig-cli install
  swig
  
  # OR local swig-cli install
  npx swig

• Run a task:

  # Global swig-cli install
  swig yourTask
  
  # OR local swig-cli install
  npx swig yourTask

Swigfile Syntax Options Matrix

Your swigfile can be one of the following:

• swigfile.cjs
• swigfile.mjs
• swigfile.js
• swigfile.ts

If there are multiple swigfiles in your project directory, swig will use the first one it finds, using the order above. The following shows the various options for your swigfile file extension, package.json type and javascript/typescript syntax flavor to use.

Swigfile	package.json type	Syntax	Notes
.js	module	ESM
.js	commonjs	CommonJS
.cjs	any	CommonJS
.mjs	any	ESM
.ts	commonjs	CommonJS	Must have valid tsconfig.json options. Must use ts-node and NOT tsx for CommonJS.
.ts	module	ESM	Must have valid tsconfig.json options. Must have either tsx or ts-node installed.

If using typescript:

• You must install either tsx or ts-node as a dev dependency in your project. These are Node typescript loaders that allow immediate execution of typescript without a transpilation step. Note that tsx ESM functionality is advertised as being experimental, but it seems to work well, and also seems to have fewer issues than ts-node, and is much faster. You can install one of these by running npm i -D tsx OR npm i -D ts-node.
• In a typescript project where the package.json is set to CommonJS, you will need to use ts-node and NOT tsx
• Your tsconfig.json needs to have settings that match your package.json type. For example, if you have your package.json type field set to module, then your tsconfig.json needs to have a module setting of "ES2020" or "ESNext" (something that supports ESM). See Swig Typescript Quick Start for an example tsconfig.json file.
• If using ts-node, speed up execution time by configuring it to skip type checking (this is only required for NodeJS version 18.19 and above):

  "ts-node": {
    "transpileOnly": true
  }

• Make sure your tsconfig.json has your swigfile.ts in it's include section in order to get IDE support
• If using eslint, ensure that your swigfile.ts is included in files that it checks
• If you're using swig to manage a typescript project and have conflicting tsconfig.json settings, consider using a separate file for your build, like tsconfig.build.json and build with something like tsc --p tsconfig.build.json (or alternatively, you could use another directory for swig other than your project's root directory)

Series, Parallel and Composability Example

A dev task like build might have several steps where some steps can happen in parallel and others must happen sequentially. So we define each of the steps as functions and compose them into an exported task we're calling simply build:

Sample swigfile contents:

async function buildPrep() {...}
async function buildServer() {...}
async function buildClient() {...}
async function postBuild() {...}

export const build = series(buildPrep, parallel(buildClient, buildServer), postBuild)

And then we can run it with :

// Global swig-cli install
swig build

// OR local swig-cli install
npx swig build

Example Projects

See dotnet-react-sandbox and it's use of swig-cli-modules to encapsulate tasks for projects that use it as a template.

Compatibility

NodeJS Version Support

Node.js versions >= 16 are supported.

Tested Node.js versions:

• 16.20.2
• 18.16.1
• 18.19.0
• 20.19.2
• 22.16.0
• 24.1.0

Important: NodeJS and/or tsx has a bug that prevents swig from working with tsx for 18.17.x and 18.18.x versions. If you want to use the tsx variant of swig and have one of those versions, you'll need to either downgrade to 18.16.x (or below) or upgrade to 18.19.x (or above).

Optional dependencies

Known working versions of optional dependencies for typescript variant projects:

• typescript: 5.4.5
• tsx: 4.19.4
• ts-node: 10.9.2

Additional Documentation

• ./docs/SwigSupplementalDocumentation.md
• ./docs/SwigDevNotes.md