Datadog’s Interview Process & Questions

The info below is based on conversations with Datadog engineers.

Datadog's Interview Process for Software Engineers: 3 Steps

Mid to senior-level engineers interviewing at Datadog can expect the following process:

• Recruiter call (30 minutes)
• Technical phone screen (1 hour)
• Onsite (4 hours)

General tips:

• Practice algorithmic questions that lean practical in terms of the type of work Datadog does (but practicing LeetCode questions will help do well in these – many of their questions start as a LeetCode medium and then layer on complexity/get more practical)
• Prepare to answer some technical questions about your past work during the behavioral portion of the onsite.

At Datadog, the process is centralized, which means that you won’t do team matching until after the onsite phase. You’ll be interviewed by people from different teams during the interview loop.

The entire process takes about 6 weeks, and we’ve heard it can seem quite slow at times. You might have to push to speed things up.

Step 1: Recruiter Call

Datadog’s recruiter call lasts 30 minutes, and it’s pretty standard fare – they’ll ask you about your previous experience, why you’re interested in Datadog, and what you’re looking for moving forward.

It’s really important, at this stage, to not reveal your salary expectations or where you are in the process with other companies. We’ve written a detailed post about salary negotiation that lays out exactly what to say if recruiters pressure you to name the first number.

Step 2: Technical Phone Screen

Datadog’s technical phone screen lasts about an hour and is conducted in CoderPad. You will get two questions in this interview. We will cover what we know of their question style in the section called “Types of Interview Questions to Expect at Datadog” below.

Step 3: Onsite

Onsite interview loops can vary slightly depending on the role and seniority, but the below is generally what you’ll get.

• Coding (1 hour). This interview will be conducted in CoderPad. For more detail about the kinds of questions to expect, see the Coding section below.
• [Only for roles below Staff] Second coding (1 hour). As above.
• System design (1 hour). This interview will be conducted in your choice of tool (many candidates choose Excalidraw). For more detail about the kinds of questions to expect, see the System Design section below.
• Behavioral (1 hour). This interview will be conducted by a hiring manager or director of engineering. It may feature some technical questions! For more info about what questions to expect, see the Behavioral section below .
• [For Staff level roles and above] Presentation (1 hour). This will replace one of the coding rounds. You will be asked to present a project you’ve worked on in the past to a panel. You’ll be expected to justify the technical decisions involved and explain the business context or rationale for what you did. If you do this interview, you may have to pick teams you're interested in beforehand so people from those teams can attend.

Types of Interview Questions to Expect at Datadog

Coding

From the first technical phone screen through to the onsite coding rounds, you should expect algorithmic questions but likely NOT questions taken verbatim from LeetCode – Datadog has their own internal question bank. We’ve heard that the questions are a hybrid between practical and LeetCode-style. They might start with something similar to what you can find on LeetCode but then layer on additional complexity. Datadog themselves recommend practicing medium-level LeetCode questions. You might be asked questions like these:

• Bucketing numbers given specific requirements
• Given a root directory, find the total size of all the files across all sub-directories
• Given an interface and a file class, build a buffered file writer

Below are the technical topics you’re likely to encounter in Datadog interviews. To compile this list, we did two things. First, we spoke to some current and former Datadog engineers. Then we cross-referenced all the anecdotes we heard with Glassdoor data AND our own data-set of mock interviews:

System Design

We’ve heard that this round is less broad than it can be at other companies. You won’t be asked to “Design Twitter”, for example. Instead, you might get a question such as, “Given a service that returns flight deals for the last 7 days, design a system that surfaces relevant flight data to a user and notifies the user when there’s a new flight that matches their criteria.”

As one of our users said:

"[I] didn’t have to go into detail in every area. They kept it very high level, and the interview felt fair.”

While it might be a fair interview, it’s also used for leveling so make sure to brush up on system design. We’ve heard of candidates being down-leveled for less-than-flawless performance here.

Check out our guide to system design interviews to help you prepare.

Behavioral

This interview will be with someone in a leadership role at the company, possibly a director. It will contain some standard behavioral questions but also some technical questions about your past work.

You might be asked to show a simple design of something you built at a previous company. The interviewer will want to know why certain design choices were made so they can understand your impact on the project and your level of experience working within teams.

How Datadog Makes Hiring Decisions

After a successful onsite, a Hiring Committee will decide if you should be hired.

If they want to make an offer, your profile will be shared with multiple hiring managers for team matching. You’ll get a chance to meet a few people from the team including the hiring manager. This is more about you figuring out a good fit than being a continuation of the interview process.