Avoid unnecessary builds, tests, lint and more in your monorepo CI. Optimize your development process by intelligently finding affected dependencies and selectively triggering builds and tests only when needed.

CI pipeline runtime is a precious resource, and in order to keep it as short as possible, we need to run only the necessary builds, tests, etc..

The way Nx affected algorithm works is by finding all changed projects in the current branch by file path and return the "affected" projects by the dependency graph.

This is not always accurate, as a change in a file can be a simple change in a comment, or a change in a function that is not used by a dependant project.

In Lemonade we have several big monorepos with complex dep graph, and we found that the affected algorithm causes us to run unnecessary tasks, which increases the CI runtime and slows down the development process.

This is where true affected comes in. It will find the affected projects by lines changes in the current branch.

• @traf/core
• @traf/nx
• @traf/turbo

A library that finds affected projects in a monorepo, based on the changed lines in the current branch.

npm install @traf/core

import { trueAffected } = from '@traf/core';

const affected = await trueAffected({
  rootTsConfig: 'tsconfig.base.json',
  projects: [
    {
      name: 'proj1',
      sourceRoot: '<project source>',
      tsConfig: '<project source>/tsconfig.json',
    },
    // ...
  ],
})

rootTsConfig - The path to the root tsconfig file, should include the paths prop with all projects mapping so ts-morph can find the references.

The algorithm is based on the following steps:

1. Using git to find all changed lines in the current branch.
2. Using ts-morph to find the changed element (function, class, const etc..) per line.
3. Using ts-morph findReferences to find all references to the changed element recursively.
4. For each reference, find the project that contains the reference and add it to the affected projects list.

A cli tool that wraps @traf/core to be used with Nx.

Will automatically find all projects in the nx workspace.

npx @traf/nx@latest affected <action> [options]

A cli tool that wraps @traf/core to be used with turborepo.

Will automatically find all projects in the workspace.

npx @traf/turbo@latest affected <action> [options]