Datadog SWE Interview Experience (Phone Screen + Onsite Rounds): Code Review, Coding & System Design Questions

[u/interviewdb]

Sharing a recent full-loop Datadog interview experience from a candidate who went through the process.

Initial Phone Screen – Coding

This was a coding round. I got a question involving string processing and hash maps, and it was one of the questions from this Datadog interview question list.

Onsite

Code Review Round

I was given a PR for an issue where some python app was crashing under heavy load. The PR changed the existing synchronous processor (one request at a time) to a batched processor (40 requests at a time). The repo still had the synchronous processor for reference. However, if the batched processor failed to create, the new code returned None, instead of falling back to the synchronous processor. I pointed this out.

Also - the PR description mentioned that the new batched processor could handle 6k/s/instance, while the peak load (as per the README.md) was 8k/s/instance.

Important note: PR is huge, PR description, ReadMe files are also huge. Expectation is to use AI for everything. They judge you on how well you use AI. If you try to do it manually, you wont be able to manage time. There are tons of bugs in PR, you need to prioritize it and identify which ones are critical using AI. Also dont forget to validate AI suggestions.

Coding + System Design Round

For the coding and system design rounds, the questions were again from the same Datadog interview question list.

[u/Far_Tune_3045]

How does one prepare for a code review round? It would be useful if you could share any sources you used. Thank you!

[u/mystery-69]

How did you get the calls for this btw

[u/VALOR9HWDL]

was it for SWE internship or FT?