Datadog Interview Questions
& Process for Software Engineers

Datadog’s coding problems open easy on purpose. You clear the first version, and then the interviewer starts bolting load onto it, one rung at a time: the directory walk that stops fitting in memory, a Premium question that has to become a ring. How far up that ladder you get is what sets your level, so spending the hour making the opening version elegant is the most expensive thing you can do with the clock. Four to eight weeks end-to-end, and as little as two with a referral, starting with a recruiter screen, then a live technical screen, then a virtual onsite of roughly five hours.

There is no whiteboard anywhere in the loop. You write and run real code in a shared editor, usually CoderPad, in the language you actually work in. The problems come from Datadog’s own practical bank rather than verbatim LeetCode, and they carry more setup than the task needs, so the first minute of a round goes on finding the one sentence that says what to build. That verbose, observability-flavored prompt is the signature whether it shows up in the phone screen or the onsite.

The first technical round is live coding in CoderPad, and your code runs. Two problems is the norm, and the pair candidates report most often is a Premium question followed by a directory-size walk. Both prompts are dense and under-specified, and both escalate through follow-ups, so the hour rewards pacing over polish. One immaculate solution shows the interviewer about half of what they sat down to see.

Tests are frequently an explicit ask. More than one candidate has been told, in so many words, to use tests to demonstrate the function is correct, and that is worth taking literally: write two as you go rather than describing at the end the ones you would have written. The gaps in the prompt want the same treatment. Deciding quietly what an ambiguous line meant and getting it wrong costs you the follow-ups that were supposed to sit on top of it. The prompts come straight from Datadog’s own domain, and the collection agent that does this work in production is open source on GitHub.

The onsite is a set of practical rounds rather than back-to-back algorithm puzzles, and the core is stable across reports: two coding rounds, a system design round, and a values round, with a project deep-dive either bolted on as a fifth or folded into values. At Staff, one of the coding rounds gives way to that deep-dive, so the higher you aim the more of the loop gets spent on work you have already done rather than work you do in the room.

Practical Coding

Two of these. A verbose, observability-flavored prompt you build out in CoderPad: walk a filesystem, parse a log stream, wrap a Premium question. You write your own tests and run the code in your own language.

The Follow-Up Ladder

Each coding problem starts easy, then the interviewer keeps adding load. The directory walk runs out of memory; the buffer has to go circular. How far up the ladder you climb is the real leveling signal, so coding fast enough to reach it matters.

System Design

Narrower than FAANG and observability-native: design a metrics pipeline, a log-search service, or a feed that watches a stream and alerts on a threshold. This is where most senior rejections land.

Values

Run by the hiring manager or a director, in the spirit of Amazon-style behavioral questions. Ownership, conflict, and feedback, weighed against Datadog’s culture of pragmatism and end-to-end ownership.

Deep Dive

A senior engineer walks one real project with you and probes your actual contribution. Sometimes its own round, sometimes folded into values. It helps set the level you land on.

Correctness and readability outrank optimization at every stage, and interviewers say so out loud, mid-round and unprompted, which is more honesty than most loops hand you. The second axis is communication, and it carries more weight than the round titles suggest. Strong technicals paired with weak communication is a familiar path to a no-hire, because Datadog runs a writing-heavy, remote-first culture and tests for it.

Decisions come together in a post-loop debrief, and hiring is centralized, so nobody in your loop is filling a seat on their own team and team matching waits until after you pass. The soft rounds carry full weight in that debrief. Candidates who clear both coding rounds still get rejected on system design or values, and one weak round sinks loops that were otherwise strong.

“Focus on writing readable, clean, maintainable code, not just optimization.” A Datadog interviewer, mid-loop.

The public IC ladder runs Software Engineer I and II, then Senior, then Staff, with Senior Staff and above past that. Reports also describe an internal numeric ladder, but Datadog does not publish the mapping, so anyone handing you a confident title-to-number translation is repeating folklore. The level you are hired at sets your comp band and your next promotion clock, and it is settled before you ever see a number.

The bands below are how those titles tend to map to seniority elsewhere in the industry. The call itself gets made in the debrief, and system design performance weighs heavily in it, which puts the round that rejects the most seniors and the round that levels them in the same hour.

SWE I–II

Software Engineer · Early careerTwo coding rounds, a system design round, and a values round

Entry to feature-owning

SeniorSD-depth gated

Senior Software Engineer · Team scopeSame skeleton, with a deeper system design bar

Maps to Senior elsewhere

Staff+

Staff Software Engineer · Multi-teamA coding round gives way to a project deep-dive / presentation

Staff and above

Average total compensation by level, per Levels.fyi (US, as of Aug 2026); self-reported and rounded. Equity is public DDOG stock. The overall median package is about $305K, and Senior Staff and Principal have too little public data to show.