The Software Developer’s Guide to Interviews

I’ve just completed a round of interviews for developer roles, and thought it would be useful to post some thoughts on the process. In particular, I wanted to document what the interview can tell you, the interviewee, about the role and the company you are applying to. There are plenty of guides telling you how to prepare for an interview. I don’t know of any that tell you how to review an interview and use that information to rate the different positions and companies you’re applying to. I suspect most people just go with their gut instinct, which is usually right, but doing a systematic review may help you realise why you prefer one job offer over another.

TL;DR Version

How a company behaves during the recruitment process is a good indicator of its internal culture and what it would be like to work there.

The Ideal Recruitment Process

From my experience of both interviewing and attending interviews for developer roles, a good recruitment process will follow most of these steps:

• Write the Job Specification - The job advertisement will be based on the job specification for the role. This should specify both the essential and desirable skills and experience that applicants should have.  If possible, this should be initially be developed by senior team members for the new role. In my experience however, the larger the company, the less influence the team will have on the job specification. If you are really unlucky, the job specification will simply be a generic description for that role in the company hierarchy, and will have no information on the work you will actually be doing.
• Form an Interview Panel - At a minimum, this should consist of a manager (preferably the manager the new hire will report directly to) and two technical interviewers (as it is harder to bullshit two people at the same time!). I personally prefer to have a member of HR also present – this helps keep the manager honest and prevent them stretching the truth when attempting to attract candidates. This is a particular issue for benefits like remote working that may not be explicitly set out in a contract. In general, the larger the interview panel, the more seriously a company takes recruitment.  A manager may also wear a technical hat, so you may only have 3 people in the panel. The interview panel will typically be responsible for setting the interview questions and defining a criteria for scoring answers.
• CV Screening - The interview panel review the submitted CVs to the job specification and draw up a long list for interviews. This may happen after a closing date for applications, or as applications are received.
• Telephone Screening - This is generally a 15-20 minute call from HR to discuss the application, and confirm that the applicant meets the role requirements.
• Technical Screening – This can be a telephone interview with a senior developer discussing the interviewee’s technical background and asking a number of set technical questions.Alternatively, this may be an online programming assessment such as Codility or an onsite technical test as part of the actual interview.  The aim of the technical screen is to confirm that the applicant does have the necessary skills and experience required for the role.
• Interview - Obviously this should be an interview with the full interview panel, who each assess the interviewee on a number of pre-set questions for which the panel have identified key answer criteria.  Typically, this would include questions on the applicant’s CV and past experience, questions specific to the role requirements and also soft skills, and then a number of technical questions.  The technical questions should cover more than just the basic job requirements – the questions should cover a range of technical levels and start at core, fundamental concepts and build to advanced topics.  The idea is to identify exactly how technically competent the interviewee is.  These questions should stretch every applicant to some extent, and will be long form in format, to allow the interview panel to force the applicant to to deep dives on specific topics. Additionally:
  • The interview described above will typically take 2 hours to complete.
  • For a developer role, this should always include some form of live coding. This is regardless of whether a technical screen was done previously or not – I’ve came across  too many developers who can BS their way through telephone screens and interviews but who are unable to code.
  • At the end, the panel leader should tell the interviewee how and when they hear the outcome of the interview.
• Post Interview Review - The interview panel reviews each applicant immediately following the interview, and scores them using the agreed scoring criteria.  The panel’s aggregate score for each interviewee is used to decide who gets the job.
• Job Offer – The post is offered to the successful applicant and their references are contacted.
• Inform all Applicants – Once the job has been accepted and the references confirmed, HR should respond to all the unsuccessful applicants. This should be within the time period specified at the end of the interview. Ideally, this shouldn’t be longer than a week, but depending on salary negotiations and references, can take longer. For an automated recruitment process, this may be an online status on the candidate’s application and/or an automated email. Preferably, it should a personal response from HR, either by email or, rarely these days, a letter. 

Based on the above outline, you can see that the recruitment process is a major investment by a company over several months, with no guarantee of a successful outcome (i.e. finding a suitably experienced applicant who will accept the position within the given salary limits).  Your interview may only last an hour or two, but by comparing your experience of a company’s recruitment process to the above, you can get a sense of how they value employees, and what it would be like to work there.

Your Interview Review

OK, so you were lucky enough to be shortlisted, and you’ve just had your interview.  Sorry, but now you going to take 10 minutes to review the interview and your experience with the company.  I typically write these review notes at the end of a document I create for each job application, detailing the job requirements, company background and any questions to ask at the interview. I then update the document with any relevant notes each time I have an interview or call with the company, so I can track exactly how the application is progressing.

The points you need to consider are:

• How has the company communicated with you since you applied to the position?  Has it been a single person communicating to you, or several, or an automated process? How did you find it – personal or completely anonymous?  How the company treats you as an applicant will typically reflect how it will treat you as an employee.
• Was there a telephone screening interview with HR?  This is not essential, but is best practice. If it happened, it is confirmation that the company has a defined interview process.  What questions were asked?  You obviously recorded the questions, and any useful information, to prepare for your interview.  From the questions asked, you can also get a good idea of what the panel will focus on the interview, and get a better idea of the work you will actually be doing.
• How were you tested technically?  Were you sufficiently tested? This isn’t a minor point.  If you were not tested on your knowledge and experience, then the people you will be working with will not have been tested either.  That means you will likely be working alongside some developers who don’t have the skills or experience for the job they are doing.  You might be the person who ends up carrying them.
• Did you have to write code as part of your interview process?  If not, this is a major failing. If the company doesn’t know if you can code or not, what is the point hiring you?
• How large was the interview panel?  This is most visible way of assessing how important a company views recruiting developers.  I would be very wary of accepting any offer from a company with less than 3 people on the interview panel, regardless of the size of the company.   Even a one person start-up should be willing to hire HR and technical consultants to have a proper interview panel. If they don’t, they haven’t a clue and you shouldn’t waste your time with them.
• The interview itself:
  • Were the questions asked relevant to the work you believe you will be doing? 
  • Did the questions asked match the advertised job?  If it doesn’t, it is likely that the job advertised won’t be the job you will actually be doing. This means that the team doesn’t have much influence on other departments in the company – this may reflect that the team you will be joining is low down in the company’s hierarchy and priorities.
  • The interviewer’s personality and  behaviour. Were you treated with respect?  Would you like to work with these people?  Remember, in an interview, people are on their best behaviour on both sides of the table.  If you come out of an interview thinking that one of the interviewers was a pain, then they will be most likely be a complete bastard to work with. You need to trust your gut instinct about people.
• How was the outcome communicated to you?  Was it done within the time frame set out by the interview panel?  I’ve known companies to pompously rant on about interviewees not attending interviews. The same companies will then completely ignore all unsuccessful applicants once the post is filled – this is extremely disrespectful behaviour.  If you’ve applied for a position, you will have spent several hours updating your CV, writing a custom covering letter, as well as preparing for and attending interviews.  At the very least, you deserve an email informing you that you have been unsuccessful.

Once you have completed the review, you will have a better idea of the company you may be working with. Obviously, this is only directly useful if you are offered the post, and if you have the option to refuse the offer.  Fortunately, experienced developers typically do receive multiple offers, and having an idea of the company’s culture can help you decide which offer is the best for you.  Also, even if you aren’t successful, it informs you on whether this is a company you want to apply to again in the future.

Case Study: Kana

My recent application with Kana in Belfast was one of the worst recruitment experiences that I ever had. I thought it would be worthwhile to share some notes I made after my interviews with Kana:

• There was a brief telephone screening interview with HR, consisting of some standard questions about my CV and past experience.
• At the first interview, I was interviewed by the team leader and a senior developer from the team I would be joining if successful. There was no one from HR present. It was a standard interview walking through my past experience and testing my technical ability. Overall it lasted around 90 minutes and was reasonably thorough. There was no coding test or any technical screening aside from the questions asked during the interview. There were a number of questions asked around my commute (I live 50 miles away from where the company is located) and my availability to work late that suggested that this is a team under significant pressure. The actual job did sound interesting (a nice mix of technologies,with a mix of both front- and back-end development), but there were a few red flags, like the focus on being able to work late.  The team leader also had a habit of talking over the senior developer that suggested they might be difficult to work with. At the end of the interview I was told I would get feedback about the interview in 2 weeks.
• At the second interview (just under 2 weeks later), I was interviewed by the VP for Development and the Principal Architect.  It lasted approximately 60 minutes.  They asked almost exactly the same questions as had been asked at the first interview. I was also told that the role would involve a significant amount of work with Clojure, and relatively little with .NET, despite the role being advertised as a .NET Developer role with no mention of Clojure in the job description. I found the VP to be very brisk in manner, and the Architect while friendly, came across as extremely bored. Obviously, there were a number of issues here:
  • Why were the same questions being asked again?  Did the second interview panel either not speak to the first, or do they not trust their opinion?  Either way, there is a communication issue here.
  • Again, same focus on my commute and on being able to work long hours.
  • The second panel’s interpretation of the role (more Clojure, less .NET) differed from that of the first interview panel and job advertised.  Who is right?

At the end of the second interview, I was told I would be informed within a week if I had been successful or not. Both interviews were held in January 2015. It is now over 2 months later and I haven’t heard anything from Kana, despite sending a polite email asking for some feedback a few weeks ago.

It will probably come as no surprise, but I wouldn’t recommend applying to Kana based on my experience.

What has your experience been in interviews?  Do you have your own way of reviewing job applications?  Please share in the comments below.

Thanks to Toby Osbourn for reading a draft of this post. You should read Toby’s blog Development Thoughts where he posts great articles on Ruby and web development.