What paths should we cache in CI?

[PaulRBerg]

When using Bun, the actions/cache GitHub Action recommends caching only the ~/.bun/install/cache path:

- uses: actions/cache@v4
  with:
    path: |
      ~/.bun/install/cache
    key: ${{ runner.os }}-bun-${{ hashFiles('**/bun.lockb') }}

Is that correct and what you as maintainers of Bun would recommend, too?

If yes, why does node_modules not have to be cached?

[thelovekesh]

By caching node_modules, you'll be reusing the same ones over and over, which could lead to unexpected issues, such as Bun resolving dependencies incorrectly, failing to prune dependencies properly in previous versions, or other potential problems.

On the other hand, by caching Bun’s cache, Bun will regenerate the node_modules directory for you. During this process, it will rely on Bun’s cache, eliminating any possibility of corrupted node_modules or other unexpected issues.

Another use case to consider is lifecycle scripts. If you have pre- or post-install scripts, caching the node_modules would prevent the install command from running, which could cause unexpected behavior. But when you cache Bun’s cache, these issues are avoided with nearly no extra time since Bun package manager is blazingly fast ⚡.

[Jarred-Sumner]

Is that correct and what you as maintainers of Bun would recommend, too?

Yes but probably **/bun.lock nowadays that we default to bun.lock.

- uses: actions/cache@v4
  with:
    path: |
      ~/.bun/install/cache
    key: ${{ runner.os }}-bun-${{ hashFiles('**/bun.lock') }}

If yes, why does node_modules not have to be cached?

Generally, bun install is faster than the github actions cache.

[PaulRBerg]

Thanks, Jarred!

I didn't know about bun.lockd — is there any command for migrating bun.lockb to bun.lock?

bun install is faster than the github actions cache

Interesting, so would you recommend not even using the GitHub Actions workflow?

[RiskyMH]

You can migrate with bun install --save-text-lockfile.

Also I'd recommend skipping the cache but still using github actions as its powerful and simple (unless as earlier mentioned with heavy postinstall as then cache could have benifit)