What we mean by "stack" on this site
When we say a company "uses" a particular language or tool, we usually mean one of two things: it is a well-documented, current part of how the product runs today, or it was a well-documented, historically important decision, even if the company has since moved on from it.
We try to make clear in each explanation which kind of fact we are describing. A company that started on one framework and later migrated is not "wrong" in our directory; the migration itself is usually the more interesting story, and we would rather tell you about it than pretend the stack never changed.
Stacks change. This content should too
Engineering teams rewrite services, retire old infrastructure, and adopt new tools constantly. We update this directory and quiz bank when we learn something has changed, but if you spot something outdated, we would genuinely like to know. Treat every fact here as "true as of when it was written and worth double-checking before you cite it elsewhere," the same way you should treat any single source on a fast-moving topic.