How do I include local TS sources in my Next.js project and iterate on them in parallel with the Next.js app?

[bduffany]

I have some GitHub repos on my local machine which have some shared "utility" code that I would like to iterate on in parallel with my Next.js projects. My Next.js projects are written in TS and so is the utility code.

Let's say I have the following two repos:

• A TS-based Next.js project, with package.json["name"] == "app", cloned locally to app-local and stored on GitHub in the app-gh repo.
• A TS-based utility project named "utils" in package.json["name"] == "utils", cloned locally to utils-local and stored on GitHub in the utils-gh repo.

I don't want to go with the "monorepo" approach because I don't want to include the utility code in the app's repo.

Ideally I'd have a workflow like this:

• I can easily link utils-local to app-local so that any references like import foo from 'utils/...' will import the current TS sources from utils-local, so that I can develop utils-local and app-local in parallel.

• When ready, I can push a new version of utils-local to utils-gh and then pin the current version of app-local to that version.

• Ideally there's some way to prevent me from forgetting to pin the version before pushing app-local to app-gh.

Does anyone know a good way to do this? Or, are there alternate workflows to achieve the same goals (iterating on separate repos with a fast edit/refresh cycle)?

I've tried using yarn link but to no avail, because Webpack refuses to load those files through ts-loader and I get a compile-time error when running next dev. Even if I add "node_modules/utils/src/**/*.*" to the "include" field of tsconfig.json in app-local, it doesn't work. It also doesn't work if I add the resolved symlink location: "../utils/src/**/*.*"

Do I need to tweak Next.js's Webpack config in order to configure ts-loader to allow my locally linked sources? If so, how do I go about that?

[bduffany]

Update: I came across https://github.com/martpie/next-transpile-modules, which gets me part of the way there. It seems to work well with yarn link. Now I just need to figure out how to avoid shooting myself in the foot by forgetting to unlink the local package before deploying... I'd love to know if anyone has figured out a solution.