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by Eridrus 175 days ago
Atomic changes are a lie in the sense that there is no atomic deployment of a repo.

The moment you have two production services that talk to each other, you end up with one of them being deployed before the other.
2 comments
oooyay 174 days ago
Atomicity also rarely matters as much as people think it does if contracts are well defined and maintained.
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Eridrus 174 days ago
A selling point of monorepos is that you don't need to maintain backwards compatible contracts and can make changes to both sides of an API at once.
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array_key_first 174 days ago
If you have a monolith you get atomic deployment, too.
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yencabulator 172 days ago
You lose atomic deployment and have a distributed system the moment you ship Javascript to a browser.

Hell, you lose "atomic" assets the moment you serve HTML that has URLs in it.

Consider switching from <img src=kitty.jpg> to <img src=puppy.jpg>. If you for example, delete kitty from the server and upload puppy.jpg, then change html, you can have a client with URL to kitty while kitty is already gone. Generally anything you published needs to stay alive for long enough to "flush out the stragglers".

Same thing applies to RPC contracts.

Same thing applies to SQL schema changes.

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array_key_first 171 days ago
They just refresh the page, it's not a big deal. It'll happen on form submission or any navigation anyway. Some people might be caught in a weird invalid state for, like, a couple minutes absolute maximum.
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yencabulator 171 days ago
If you're not interested in solving the problem, then don't claim to solve the problem.
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array_key_first 170 days ago
Right, there's level of solutions. You can't sit here and say that a few seconds of invalid state on the front-end only for mayyyyybe .01% of your users is enough to justify a sprawling distributed system because "well deployments aren't atomic anyway!1!".

IMO, monorepos are much easier to handle. Monoliths are also easier to handle. A monorepo monolith is pretty much as good as it gets for a web application. Doing anything else will only make your life harder, for benefits that are so small and so rare that nobody cares.

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yencabulator 170 days ago
Monorepo vs not is not the relevant criteria. The difference is simply whether you plan your rollout to have no(/minimal) downtime, or not. Consider SQL schema migration to add a non-NULL column on a system that does continuous inserts.
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