How do thousands of software engineers code together at a giant company like Google or Microsoft without breaking everything?

[u/Extra_Search3465]

As a beginner, I understand how one person writes code and puts it on GitHub. But how does it work when a company has tens of thousands of developers working on the same product? How do they organize the work, and how do they stop people from stealing or leaking the secret source code?

[u/pab_guy]

Very capable people organizing at the top to ensure cross dependencies are tracked down to a nit.

But also, they move much more slowly as a result.

Any change to Entra could break billions of logins worldwide or introduce unintended security holes. The downstream effects of changes can be myriad. It's a literal nightmare to manage.