DoorDash Software Engineer Interview Experience — A Two-Day Virtual Onsite After the DashMart Phone Screen

Vendor recruiter call

After the referral, I got an email scheduling the vendor recruiter call and the phone screen separately. This round was just going over my resume and checking whether there was overlap with the target team. The whole thing was 10+ minutes, and the questions felt pretty targeted.

Phone screen

A senior manager, and I got the DashMart problem. I hadn't looked at any write-ups beforehand and somehow finished it cold in 20 minutes. Then there was a follow-up: compute the nearest Dasher for each customer. At first I kept trying to find an O(n * m) solution and eventually decided it probably wasn't feasible, so I wrote an O(c * n * m) solution instead, then fixed a few small bugs by eye and by running it. I went a little over time, but the manager was generous and gave me a few extra minutes, then spent a few more minutes taking my questions.

After the interview I felt like the conversation had been really comfortable, and I thought to myself, it'd be great if the hiring manager turned out to be this person (lol). Sure enough, a week later the recruiter said I'd passed and that the feedback was very good, and that we'd schedule the HM chat next.

HM call

The hiring manager and I introduced ourselves first, then he asked about my background. I spent a good chunk of time listening to him talk about his project. It went okay, and wrapped up in 20 minutes.

Virtual onsite

The recruiter said I could split the onsite across two days, and I took that option without hesitation — otherwise I'd have been wiped out.

• System Design: Notification System. The interviewer seemed to be in a really good mood that day. One deep-dive was on how to handle spikes.
• Hiring Manager: Standard questions — project experience, how I resolved disagreements, a big mistake and what I grew from it. Wrapped up in 30 minutes (not sure if that's a good sign or not), with 15 minutes spent on questions.
• Coding: Bonus Round Up. He called it "round up," but it was really more of a "next rearrangement" problem. He was fairly polite, but strict about screen sharing the whole time, and wanted my approach explained clearly before I wrote any code — I had to walk him through it two or three times before it landed. Writing the code itself only took 10 minutes. The follow-up was the negative-number case, and after I finished there were five or six minutes left for questions.
• Project deep dive: A senior interviewer, apparently one of the founding engineers. He sat and talked casually like someone senior, but his English accent was heavy and a bit halting, and he seemed like he'd been in meetings all day and was worn out (lol). The project I'd prepared turned out to be fairly complex, and I felt like some of it went over his head, though he did ask one or two questions throughout, without giving much of a reaction either way. After 40 minutes I mentioned I'd actually prepared a second project — he seemed tired of listening and told me I could just ask him questions instead. So we talked for 10 minutes, touching on industry trends and that kind of thing. There were still seven or eight minutes left after I wrapped up the second project, and I decided to just let him go. He came off a bit casual early on, but got more polite as it went.

All the interviews were in the afternoon. The lesson I took away: don't schedule the project deep-dive too late in the day, or the interviewer is likely to have been in meetings all day and completely burned out by then (lol).

Overall it was concise and efficient, and the experience was decent — most of the interviewers were fairly professional. I got the result on the morning of the third day after the interview. I actually felt like I'd answered reasonably well; anyway, moving on. By the way, all the scheduling was done through a scheduling tool, which was miles better than the manual scheduling some other companies use.