Transitioning from Yarn to PNPM: Our Experience

We successfully migrated all of our applications and web apps from yarn to pnpm without any issues. However, when it was time to migrate our continuous integration (CI) system to pnpm, we faced a challenge. Previously, we were able to install yarn easily by using the node image on circleci.

Upon attempting to integrate pnpm ci using the provided documentation, we faced an issue where we received an error message indicating that we were denied write access.

ERROR  No write access to the found global executable directories
The found directories:
  /usr/local/bin

Using the original code from https://pnpm.io/continuous-integration#circleci

  - restore_cache:
      name: Restore pnpm Package Cache
      keys:
        - pnpm-packages-{{ checksum "pnpm-lock.yaml" }}
  - run:
      name: Install pnpm package manager
      command: |
        curl -L https://pnpm.js.org/pnpm.js | node - add --global [email protected]
  - run:
      name: Install Dependencies
      command: |
        pnpm install
  - save_cache:
      name: Save pnpm Package Cache
      key: pnpm-packages-{{ checksum "pnpm-lock.yaml" }}
      paths:
        - node_modules

We started searching the internet for a solution to the problem we encountered. After some trial and error, we found a solution that involved using the "--prefix=$HOME/.local" option during installation. This option specifies the directory where the package will be installed and can help resolve issues related to write access. By specifying a location in the user's home directory, we were able to successfully install the package without encountering any further errors.

  - restore_cache:
      name: Restore pnpm Package Cache
      keys:
        - pnpm-packages-{{ checksum "pnpm-lock.yaml" }}
  - run:
      name: Install pnpm package manager
      command: |
        npm install --prefix=$HOME/.local [email protected] -g
  - run:
      name: Install Dependencies
      command: |
        pnpm install
  - save_cache:
      name: Save pnpm Package Cache
      key: pnpm-packages-{{ checksum "pnpm-lock.yaml" }}
      paths:
        - node_modules

We realized that we needed to use a cimg image that had node installed in order to proceed. Once we made this change, everything worked smoothly, and we immediately noticed a significant increase in speed compared to when we were using yarn.