"Merging" features of two apps

How To
1

I have two separate apps both using the same frameworks (node, vite, tailwind, mongo etc) and both in a monorepo.

One of the apps has 15 different tools and calculators. I’d like to essentially merge those features into the other app so that they are identical and then import data from the mongo collection so that users can access their tools and calculators on the app where we are merging into.

I say “merge” as I want them to be identical but I assume it’ll be easier to just have cursor rebuild the apps then to actually try and merge things.

What’s the best way of doing this? I’d like the database model to be the same as well as the UI.

Should I just copy all of the files to the working app and tell cursor to create versions functionally identical? Is there a better way of doing this?

Thanks

2

I’m far from an expert, but I might tackle it like this:

  • I’d make them into a ‘monorepo’ (copy the 2nd app into a subfolder to avoid filename conflicts).
  • Depending on size use Gemini 2.5 Pro (MAX or on Google’s website if you need really large context) to understand the codebases.
  • Use o3 to create a PRD for merging functionality.
  • Have it broken into manageable tasks (separately, or in the step above)
  • Create a new git branch (/feature-merge or whatever)
  • Have the necessary changes made in the new branch.
  • Merge branches when finished.

Depending on the complexity of the features, re-creating them might be easier. You could have a PRD created from the 2nd app (steps to recreate from scratch), and work from that.

3

thanks for the response