Snowpack monorepo

[edmulraney]

I couldn't find much literature on Snowpack monorepos so had a go at setting one up using Yarn workspaces, Typescript, and React with Fast refresh.

I wanted a monorepo with three packages:

• components - a UI component library
• launch-kit - a "framework" which uses components
• app - an application which uses the launch-kit framework
  i.e. app -> launch-kit -> components
app is the entry point

The monorepo needed to have:

• shared Typescript tsconfig
• shared Prettier config
• fast refresh (hot reload while preserving state) working in app even if the code change comes from components (which isn't a direct dependency of app).

The following repo has this all working: https://github.com/edmulraney/snowpack-monorepo

This screenshot shows HMR updates coming from the different packages while the countdown timer state is preserved.

To enable this I had to make these changes:

• for app package: add mount entries for each other monorepo package (used either directly or indirectly in app)
• for app package: add an alias for each other monorepo package
• for all packages: add a snowpack.config.js which includes React fast refresh and Typescript plugins

I believe I found a bug in Snowpack while building this. If you make your package.json dependencies external (using snowpack packageOptions.external), Snowpack fails to build. I've raised a bug for this here: #2560

Other than that, everything else is working well across the monorepo, including TypeScript, which is really great to see :)

Has anyone else tried building something similar? Is there something I'm missing with this approach? Is there a better approach?

[simonchuryakov]

I've tried building a similar monorepo and faced the same issue. I've also created a repo to reproduce this issue even without monorepo approach - https://github.com/simonchuryakov/snowpack-external-modules-issue

Snowpack requires to have at least 1 dependency to be bundled in modules/pkg, because if I remove react-dom from the packageOptions.external, build succeeds. to me it looks like a bug

[fgblomqvist]

@edmulraney you'll probably have better luck if you post your bug under "issues" instead 🙂 (but yes, I also hit that bug)

[edmulraney]

@edmulraney you'll probably have better luck if you post your bug under "issues" instead 🙂 (but yes, I also hit that bug)

I started doing that but it advised me to make a discussion first :D

[fgblomqvist]

Haha okay didn't know. I guess we need @FredKSchott to confirm it before an issue can be filed then perhaps?

[FredKSchott]

I believe that this has been fixed in #2707 along with a bunch of updates for monorepos. Would love your feedback if you can check out that PR (npm install snowpack@next)

[karolis-sh]

Hey @FredKSchott, is there a way to exclude monorepo modules from the Snowpack pipeline? I have CJS only modules, and the Snowpack app tries to handle them directly, while it should treat them as any node_modules package.

[karolis-sh]

I have a minimal monorepo structure, but it works with an older Snowpack version "snowpack": "^3.0.11" only, anything never breaks 🙈