Using Peer Dependencies With Local (file:../some-lib) Dependencies

I have a monorepo that has many micro-services in it. There are some library-type functions / classes that I want to make available to any micro-service that needs it. However, if that library package declares a peer dependency, the peer dependency is not found when running code from within the thing that depends on the library. Consider this repo structure: - lib - some-library (peerDepends on `foo`) - index.js (requires `foo`) - node_modules will be empty - services - some-service (depends on `foo`, and `some-library`) - index.js (requires `some-library`) - node_modules will have: - `foo` - `some-library` will be a symlink to `../../lib/some-library` When running `node services/some-service/index.js`, you'll get the error "Cannot find module 'foo'", emanating from `lib/some-library/index.js`. Presumably this happens because node is only looking at `lib/some-library/node_modules` and any `node_modules` folder that is in an ancestor directory. But since this code was run from `services/some-service` (as the working directory), and because of the symlink in `services/some-service/node_modules`, I would've expected this to work. Here's a repo you can easily clone to see the problem: https://github.com/jthomerson/example-local-dependency-problem ``` git clone git@github.com:jthomerson/example-local-dependency-problem.git cd example-local-dependency-problem cd services/some-service npm install node index.js ``` I only see two solutions: - Don't use peerDependencies inside the library - Install each peer dependency at the root of the project for the sake of local development and testing. Neither of those is a real great solution because it doesn't allow each service to have different versions of the dependencies, and thus means that if the local version (or the library's version) of a dependency is bumped, all services that uses the library then have their dependencies version bumped at the same time, which makes them more brittle because they're all tied together.