Finished the Datadog data engineer loop two weeks ago (NYC role, hybrid). Sharing notes while they're fresh because I couldn't find much specific to the DE track when I was prepping.
Five rounds total:
Recruiter screen - 30 min, pretty standard. They asked about my pipeline experience, specifically Kafka and Spark. No gotcha questions, just making sure I wasn't a resume ghost.
Technical phone screen - 45 min with a senior DE. Split roughly 50/50 between SQL and a system design-ish discussion around pipeline architecture. The SQL was not baby stuff. They gave me a multi-table scenario involving event data (very much in keeping with what Datadog actually does) and asked me to write a query to compute rolling averages and detect anomalies in a metrics stream. Window functions, lag/lead, the works. Know your CTEs.
Take-home - They sent a small dataset and asked me to build a simple ETL pipeline, document the schema decisions, and write SQL to answer three analytic questions. I used Python + duckdb locally and wrote it up in a notebook. Took me about 3 hours but I went deep on the write-up. I think that mattered.
On-site (virtual) round 1 - More SQL plus a deep dive into my take-home. They asked why I chose my partitioning strategy, what I'd do differently at 100x scale, and whether I'd considered streaming vs batch for one of the transforms. Have answers for these in advance.
On-site round 2 - Behavioral. Focused on cross-functional work and how I handle pipeline failures in prod. Standard STAR stuff. Nothing Datadog-specific but be ready for: "tell me about a time a data quality issue made it into a downstream dashboard and what you did."
The curveball: one interviewer asked me to walk through how I'd instrument a pipeline to emit custom metrics to a monitoring system. Basically asking if I actually understand observability tooling. Felt like a Datadog-culture question as much as a technical one. Worth thinking through.
Total timeline: applied via referral, recruiter reached out in 5 days, full loop over 3 weeks. Still waiting on decision as of today.