Dream Package Manager Workflow:

My dream workflow for building native apps would look something like this:

```
git clone myApp.git
cd myApp
esy install
esy build --target=armv7 --platform=ios-sdk
esy build --target=armv7 --platform=android-sdk
```

To add a dependency, you'd be able to simply add any opam package (or package hosted on npm) to `package.json`, and then rerun `esy install && esy build --target..`.

- The dependencies don't need to anticipate being cross compiled in the majority of cases.
- The ones that do need to do something special in the cross compilation case, would use some convention for ocamlfind toolchain names and we'd provide the right hooks for that, but 90% of packages shouldn't need to worry about it (unless they define their own ppx plugins perhaps).

**Forking:**
You shouldn't need to fork packages in the common case. If we do in some cases, then we can possibly use a "resolutions" style field to consume those forks.

This is just an idea for the "dream workflow". In practice, we might need to compromise.

cc @rauanmayemir / @andreypopp

There's a lot to discuss about cross compilation, but let's keep this thread limited to the things that apply to Really Native React, or mobile.