MongoDB Interview Questions

Updated Sep 22, 2014
Updated Sep 22, 2014
27 Interview Reviews

Interview Experience

Interview Experience

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23%
14%

Getting an Interview

Getting an Interview

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Interview Difficulty

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Candidate Interview Reviews

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  1.  

    Event Coordinator Interview

    Anonymous Interview Candidate
    Anonymous Interview Candidate
    Interview Details

    Several phone interviews, was invited in and met 6 different people, all went very well. Last interview was with VP. Never heard from them again.

    Interview Questions
    No Offer
  2. 1 person found this helpful  

    Database Kernel Engineer Interview

    Anonymous Interview Candidate
    Anonymous Interview Candidate
    Application Details

    I applied online - interviewed at MongoDB.

    Interview Details

    Applied online and got a call from the recruiter. Had an initial phone screen. I answered all the questions except the C++ ones. I didn't know they were big on C++ knowledge.

    Interview Questions
    • The questions on C++ were the unexpected ones. Interviewer asked me to write a very simple coding questions, but asked me to use vectors from the C++ standard library and use iterators for iterating through those elements. I couldn't answer as C++ isn't on my resume.   Answer Question
    No Offer
    Average Interview
  3. 2 people found this helpful  

    Senior Engineer Interview

    Anonymous Interview Candidate  in  Palo Alto, CA
    Anonymous Interview Candidate in Palo Alto, CA
    Application Details

    I applied online. The process took 2 weeks - interviewed at MongoDB in July 2013.

    Interview Details

    recruiter call, technical interview with hiring manager, technical team group interview onsite, interview interview with VP. Reference check. Offer made

    Interview Questions
    • how various search algorithm O time change if it is done in parallel on multi cpu machine   View Answer
    Reasons for Declining

    better option available

    Declined Offer
    Positive Experience
    Average Interview
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  5. 2 people found this helpful  

    New/Recent Grad - Software Engineering Interview

    Anonymous Interview Candidate  in  New York, NY
    Anonymous Interview Candidate in New York, NY
    Application Details

    I applied online. The process took 2 weeks - interviewed at MongoDB in March 2013.

    Interview Details

    One phone screen. One technical phone interview coding on google docs. How would you write DB write / access functions to make sure data is not modified by threads. Parse mathematical expression given as chars in array ['1', '+', '2,' '/', '4']. Four onsite interviews over the course of 4 hours asking a variety of questions. Write algorithm to find loop in graph, write C code to convert integer to string.

    Interview Questions
    • Write an algorithm to find a loop in a graph. The graph is unidirectional with any number of connections. The graph is not necessarily connected   View Answers (2)
    No Offer
    Positive Experience
    Difficult Interview
  6.  

    Software Engineering Intern Interview

    Anonymous Interview Candidate
    Anonymous Interview Candidate
    Application Details

    I applied through other source - interviewed at MongoDB in January 2013.

    Interview Details

    3 challenges. Fizzbuzz. Find the height of a binary tree. Parsing parenthesis.

    Interview Questions
    • Given a set of open and close parenthesis, make sure the string is valid, such that each open parenthesis has a matching close parenthesis in the correct place.   View Answers (2)
    No Offer
    Positive Experience
    Average Interview
  7.  

    Technical Architect Interview

    Anonymous Interview Candidate  in  New York, NY
    Anonymous Interview Candidate in New York, NY
    Application Details

    I applied online - interviewed at MongoDB in December 2012.

    Interview Details

    The single biggest pain point was how long this took. And, every time I got a call from HR, it was to tell me that another call with someone else had been scheduled.

    In total I fielded over 12 different onsite and offsite meetings over 3 months. There were several times when I was convinced that this is a serious waste of time.

    After the technical phone screen, I went in for an in-person invterview that lasted 4 hours and there I met 4 people. That same day I received a call from one more person.

    It took 3 months to receive an offer.

    Interview Questions
    • We have a person who logs into a website using their Facebook credentials. Anything they post to that website can be seen by their friends and those friends' friends only.
      How would you optimize the collection of this data?
        Answer Question
    Negotiation Details
    I didn't negotiate. I took the base salary, stock options and bonus structure as is. I thought it was pretty fair.
    Accepted Offer
    Positive Experience
    Average Interview
  8. 5 people found this helpful  

    Solutions Architect (Customer-facing) Interview

    Anonymous Interview Candidate  in  Palo Alto, CA
    Anonymous Interview Candidate in Palo Alto, CA
    Application Details

    I applied through a recruiter. The process took 4+ weeks - interviewed at MongoDB in April 2012.

    Interview Details

    TLDR: product & company seem like a classic example of a solution in search of a problem. Probably an OK place to be a pure developer, but not a good place for customer-facing roles. Interviewers didn't seem to understand the difference between a software engineer and a solution architect.

    Details: I hadn't really been looking around, but one of their in-house recruiters reached out to me initially, and after checking around a bit I connected with him and we had an email/phone discussion. At that stage it sounded interesting enough that I subsequently invested an afternoon in meeting some of them in-person. It turned out to be a rather complete non-match from both our perspectives; I was not interested in receiving an offer and they were not interested in extending one.

    The recruiter and the HR executive I met were both pleasant and personable--people I'd hire for my own company, in both cases--but the rest of the staff I spoke to seemed rather arrogant and insecure. Mean-spirited, as an earlier reviewer commented here. I had to bite my tongue when one manager said they were staffing up on customer-facing folks because they were "ready to take on Oracle." Most of their interview questions were more appropriate for core developers than solution architects: all about algorithms, nothing about scaling, implementation, or other real-world issues. Nor did anyone seem to care about actual customer-interaction skills.

    I asked one of the interviewers whether she knew anything about an old programming language called COBOL, and what kinds of data access methods were used back in the 1960's...after all, mongodb is essentially a re-invention of ISAM-style access methods for javascript and other modern languages. Surprisingly, she had zero clue what I was talking about. More generally, no one with whom I spoke seemed to understand the difference between offline data mining types of applications and online transaction handling applications, and the different requirements of the two worlds.

    To the recruiter's credit, he reconnected with me less than 48 hours later, and we agreed that it wasn't a match.

    Interview Questions
    • Not difficult, per se, but unexpected: one interviewer asked me to name several different sorting algorithms and rank them by their computational complexity. Unexpected because I've never had such a discussion with a customer, no matter how technical; the question would have been more appropriate for an engineer being hired into their kernel group but the interviewers didn't seem to know the difference.   View Answer
    No Offer
    Negative Experience
    Average Interview
  9.  

    Software Engineer Interview

    Anonymous Interview Candidate  in  New York, NY
    Anonymous Interview Candidate in New York, NY
    Application Details

    I applied in-person. The process took 1 week - interviewed at MongoDB in November 2011.

    Interview Details

    Interviews were scheduled over one day. Process was really enjoyable. I was asked a couple of interesting coding questions to see how I think but the majority of the interview time focused on my experiences as CTO, why I was interested in working at 10gen, and what I wanted to do at the company.

    Interview Questions
    • When an interviewer disagreed about a technical choice that I had made for a website I was asked to defend my opinion and argue my point of view.   View Answer
    Accepted Offer
    Positive Experience
    Average Interview
  10. 1 person found this helpful  

    Engineer Interview

    Anonymous Interview Candidate  in  San Francisco, CA
    Anonymous Interview Candidate in San Francisco, CA
    Application Details

    I applied in-person. The process took 3+ weeks - interviewed at MongoDB in December 2010.

    Interview Details

    As a member of the open source community working with frameworks based on the product I already had a lot of experience and interaction with many people in the company. This lead to an interview and discussions about jobs before that. The interview involved multiple meetings with engineering folk and managers which resulted in a job offer. We then went and back with multiple responses before the offer was accepted. The whole process seem labored and unprofessional (informal) in many ways.

    Interview Questions
    Accepted Offer
    Neutral Experience
    Easy Interview
  11. 1 person found this helpful  

    Intern Developer Interview

    Anonymous Interview Candidate
    Anonymous Interview Candidate
    Application Details

    I applied online. The process took 2 weeks - interviewed at MongoDB.

    Interview Details

    Many interviews. Something like 6 hours all in all.
    Pretty surprised because ALL the interviews went pretty well, I even finished a couple interviews before the allowed time (because I solved the problem that was asked, and answered all the interviewer's questions)... and yet I didn't get an offer after such a lengthy interview process.

    Overall the interviewers were passionate and nice. (one exception though)

    Interview Questions
    • Some really low-level questions that are totally unrelated to the internship position I was interviewing for. I think I answered correctly, but it still was unexpected.   Answer Question
    No Offer
    Positive Experience
    Difficult Interview

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