element-call-Github/docs/linking.md

Developing with linked packages

If you want to make changes to a package that Element Call depends on and see those changes applied in real time, you can create a link to a local copy of the package. Yarn has a command for this (yarn link), but it's not recommended to use it as it ends up modifying package.json with details specific to your development environment.

Instead, you can use our little 'linker' plugin. Create a file named .links.yaml in the Element Call project directory, listing the names and paths of any dependencies you want to link. For example:

matrix-js-sdk: ../path/to/matrix-js-sdk
"@vector-im/compound-web": /home/alice/path/to/compound-web

Then run yarn install.