[blandflakes]

> First put all your services in a monorepo have it all build as one under CI. That’s a static check across the entire system.

There are definitely benefits to this approach. My coworkers do fall into the trap of assuming that all the services will be deployed simultaneously, which is not something you can really guarantee (especially if you have to roll one of them back at some point), so the monorepo approach gives them confidence in some breaking changes that it shouldn't (like adding a new required field).

[threethirtytwo]

I mean you talk about it as if it's a "benefit"

I'm talking about it in the same sense as the "benefit" of using typescript over javascript. Not just a "benefit" but it's the obvious path, the obvious better way.

Everything about monorepos and polyrepos are basically mostly just debates about opinions and styles and preferences. But most people don't understand... the monorepo is definitively better. Don't think of it as a benefit, this makes that style of error literally impossible to occur.

[blandflakes]

Well, no, it doesn't. A monorepo does nothing to prevent you from making breaking changes, it just stops you from making changes that don't compile/test. You still have to understand that services aren't deploying as an atomic unit and make sure that your network calls are forward and backward compatible.

[threethirtytwo]

I never said it stops you from making ALL breaking changes. But it makes a whole class of very common breaking changes Impossible to occur. This is a definitive benefit. Monorepo means much less errors, Polyrepo means more, every other difference between the two is a debatable opinion but this is definitive.

>You still have to understand that services aren't deploying as an atomic unit and make sure that your network calls are forward and backward compatible.

The time between inception of a deploy and the termination of a successful deploy isn't solved. But a monodeploy solves an entire class of errors outside the boundary of an atomic deploy. Think about what's in that boundary and what's outside of that boundary? How long does a deploy take? An hour? How long are you not deploying?

That's they key, static checking can't fix everything and a monodeploy isn't a full guarantee of safety, but it does guarantee the impossibility of a huge class of errors in the interim time between successful monodeploys.

[blandflakes]

Yeah, I think you're preaching to the choir about static checking, the only point I was making is that monorepo doesn't solve some classes of errors and that I've actually seen it generate false confidence in that realm.

[threethirtytwo]

Agreed. You're right it doesn't solve some classes of errors.

I guess my point is, monorepo vs. polyrepo... monorepo is the winner because it solves more classes of errors.