Virtually every developer at Datadog shudders when they hear the word "Bazel". Our approach to developer experience is so, so, broken. There's an expectation that people should build new products in (one of the several) large monorepos, but actually getting things done in those repos is brutally slow. Just launching or testing your backend service involves waiting ages for Bazel to compile a ton of unrelated code.
On top of that, we have to use a lot of bad, underdocumented, proprietary developer tooling. If you want to spin up a new REST service/Postgres instance/whatever, expect everything to take 5-10x more effort and time than it would elsewhere. You will spend more of your time learning how to do things the some-internal-team way than actually solving business problems. Edit-compile-run loops are often an order of magnitude slower than they would be at other companies.
This mess is sometimes kind of *interesting*, but it is definitely not a good way to spend software developers' time.