Settings to Run Yarn v4 (PnP Mode) in Bitbucket Pipelines

Yarn v4 in PnP (Plug’n’Play) mode is a newer package management style that does not use node_modules.

This is a short summary of how to configure Bitbucket Pipelines for building a Yarn v4 project.

Prepare the project

Create the project with Yarn v4.

yarn create vite yarn-v4-app --template vanilla-ts

Move into the directory.

cd ./yarn-v4-app && pwd

Bitbucket Pipelines configuration

Create bitbucket-pipelines.yml.

image: node:22.6.0
definitions:
  caches:
    yarn:
      key:
        files:
          - yarn.lock
          - .pnp.cjs
          - .pnp.loader.mjs
      path: ~/.yarn/berry/cache

  scripts:
    - &Init export TZ=Asia/Tokyo && corepack enable
    - &Install yarn install --frozen-lockfile

pipelines:
  custom:
    build-vite:
      - step:
          name: "Build"
          caches:
            - yarn
          script:
            - *Init
            - *Install
            - yarn build

Points

1. Enable corepack: use corepack enable so Yarn v4 becomes available
2. Cache settings: manage the cache with yarn.lock, .pnp.cjs, and .pnp.loader.mjs as keys
3. frozen-lockfile: use yarn install --frozen-lockfile to prevent lockfile changes

Summary

To run Yarn v4 in PnP mode on Bitbucket Pipelines, you need corepack enabled and the right cache settings.

Including the PnP files, .pnp.cjs and .pnp.loader.mjs, in the cache key helps keep builds efficient.