lazyrepo: A JavaScript repository from MitjaBezensek

💡 Currently in the prototyping stage, expect breaking changes! Get help or join in development on discord.

lazyrepo is a zero-config caching task runner for npm/pnpm/yarn monorepos.

It fits right into the niche that turborepo carved out: making package.json "scripts" scale without adopting a big industrial-strength build system like nx, bazel, rush, or buck.

lazyrepo is scary fast. It's a lot faster than turborepo despite being written in TypeScript rather than some young handsome clever funny systems language.

Aside from perf, lazyrepo comes with some big quality-of-life improvements:

A human-friendly config format.
Palpably sensible defaults.
Concise and timely feedback to help you tweak and debug your build pipelines.
You don't need to learn Rust to contribute.

Trust me, the whole situation is so delightful it will make you reach for the :chefs-kiss: emoji. And then you'll realize that there is no such emoji, but you'll want it so badly that you'll draft a proposal to the Unicode Consortium to lobby for its introduction.

Installation

Install lazyrepo globally

npm install lazyrepo --global

And also as a dev dependency in the root of your repo

npm install lazyrepo --save-dev

And finally add .lazy to your .gitignore

echo "\n\n#lazyrepo\n.lazy" >> .gitignore

Basic Usage

Running Tasks

Run tasks defined in "scripts" entries using:

lazy <script-name>

You can pass arguments to the task script after a --

lazy test -- --runInBand

The default behavior is optimized for "test" scripts, where the order of execution matters if your packages depend on each other.

Let's say you have three packages: core, utils, and primitives. The core package depends on both utils and primitives, and they all have "test" scripts in their package.json files.

graph TD
    A[packages/core] -->|depends on| B[packages/utils]
    A -->|depends on| C[packages/primitives]

With no config, when you run lazy test in the project root:

The tests for utils and primitives will begin concurrently. The tests for core will only be started if both utils and primitives finish successfully.
If you change a source file in core and run lazy test again, only core's tests will be executed.
If you change a source file in utils and run lazy test again, both utils and core's tests will be executed, in that order.

Other commands

lazy init

Creates a config file.
lazy clean

Deletes all local cache data.
lazy inherit

In larger projects, you often end up with the same "script" entries duplicated in lots of package.json files. Keeping them in sync can be troublesome.

lazyrepo lets you specify the command just once.

Replace the scripts entries with lazy inherit:
```
 "scripts": {
-  "test": "jest --runInBand --noCache --coverage",
+  "test": "lazy inherit"
 }
```
Then add this in your lazy config file:
```
 "tasks": {
   "test": {
+    "baseCommand": "jest --runInBand --noCache --coverage"
   }
 }
```
Now when you run npm test, or whatever, in one of your package directories, it will look up the actual command to run from your lazy config file and run that.
lazy run <task> [-- <forward-args>]

Runs the given task, forwarding any args passed after the --

You may filter the packages that a task

e.g. to test only packages that end in -utils
```
lazy run test --filter packages/*-utils
```
You may force all tasks to execute by passing the --force option.
```
lazy run test --force
```

Configuration

Create a file called lazy.config.js or lazy.config.json

To create a .js config file, in your project root run:

lazy :init

export default {
  tasks: {
    test: {
      cache: {
        // by default we consider all files in the package directory
        inputs: ['**/*'],
        // there are no outputs
        outputs: [],
        // a test invocation depends on the input files of any upstream packages
        inheritsInputFromDependencies: true,
      },
    },
  },
}

Migrating from turborepo