Yeah, we could absolutely do a better job with solid interfaces for each service. To be clear, our nextjs apps, temporal workers, etc are all well defined, and changes in a single package are easily tested (and well tested). It's integration testing we struggle with.

And, there's always a tradeoff here between engineering & our real job as a startup, finding PMF and growth. That said, we want as much eng velocity as possible and a fast, solid integration testing platform/system/etc helps a ton with that.