A sample project that shows the issues with symlinks and buck2.

You will need to install:

• NodeJS
• pnpm

This repository has a very basic pnpm workspace with two node packages - thing1 and thing2. Thing1 has a workspace dependency on Thing2.

To reproduce the issue, run:

buck2 build //:pnpm-install

You can then change the version number of thing1/package.json to a different number, and run buck2 build //:pnpm-install again. If this is the first time the buck daemon has started (and there were no node_modules directories), you will see buck2 run pnpm install due to the updated source. You can then do the same with thing2/package.json and it will also work.

Now do:

buck2 clean

Followed by another

buck2 build //:pnpm-install

Now the buck2 daemon will have the node_modules folders in the tree. If you change thing1/package.json and run buck2 build //:pnpm-install again, things will work as expected. But then change thing2/package.json - and the target will fail to register that any source has changed.

• If the buck2 daemon is started when the node_modules hierarchy exists
• And there are workspace dependencies between two packages
• Buck2 will track the symlink from thing1/node_modules/thing_2/package.json, rather than the 'real' thin2/package.json.