Should we run Rails auth on a shared dev server?

Before moving anything remote, I'd try a Docker Compose setup for the three services. One command to bring up the stack could remove a lot of the hassle while keeping each developer's code and data isolated.

That still leaves everyone running Rails locally, of course. If the main problem is resource usage rather than startup friction, a remote setup may be worth considering instead.

A remote Rails service can work, but I'd give each developer or feature branch its own instance rather than pointing everyone at one mutable development instance.

The tricky part is state, not just processes. A shared database, migration, configuration change, or bad test data can break someone else's local work. Separate instances need their own configuration and data isolation, plus a way to deploy and clean them up. You'll also want to check how local frontend and API URLs interact with authentication, cookies, and redirects.

Dev containers are another option if the pain is inconsistent tools and versions. Keep the container configuration in the project repository so changes to the toolset can be reviewed and versioned with the code.

You could also add scripts or editor actions to start the development processes together. That doesn't require putting authentication on a shared server.

I'd also ask why every task needs all three services running. If it's mostly to check that the apps agree on their interfaces, consumer-driven contract tests might cover much of that without a full stack running for every change.

That doesn't replace every integration test, particularly for authentication flows, but it could reduce how often developers need the whole environment.