How to Design a Scientific Hiring Process

Three developers having a discussion at a desk.

In The Science of Hiring, you took a deep dive into predictive validity and selection methods; now, you’re probably wondering what to do about all those numbers. Let’s explore some applications of using science to hire more effectively.

(If you haven’t had a chance to check it out part one of this series, you might want to read that first.)

The Candidate Experience

You understand the elements of a scientific hiring process, but there’s one problem:

If a candidate isn’t willing to complete your interview process, it doesn’t matter how accurate it is. You need to consider the candidate experience to increase the probability that a candidate will complete the hiring process, which gives you the best chance of making an outstanding hire.  

Even though work sample tests have a high validity when combined with a GMA, are developers willing or able to take the time to participate? Empirical data suggests that developers are tired of coding tests in any form. And a 2022 study (download the report here) reported that 71% of developers identified technical exams or tests as a pain point during the recruiting process, and 54% of developers experienced whiteboard exercises as a pain point.

Instead, you might utilize a job knowledge test and a GMA, which has the same predictive validity as a work sample test and a GMA, but could be completed in a shorter amount of time and doesn’t ask developers to complete projects or assignments.

A Research-Backed Hiring Process

All this said, there is a process for hiring developers that we have found to work, and work well. It’s backed by science and considers the candidate experience with respect for the candidate’s time. We have confidence in our ability to hire high-performing developers because our process accurately and effectively filters out candidates that would not be a good fit for the role or our team and company.

Recommended Hiring Process

  1. 30-Minute Screening Call
  2. GMA + Integrity + Personality Tests (30-60 minutes total)
  3. 1-Hour Job Knowledge Interview
  4. 1-Hour Job Knowledge Interview
  5. 1-Hour Role, Culture, and Mission Alignment Interview

Screening Call

A screening call should be no longer than 30 minutes and is usually conducted by the recruiter or hiring manager. This interview should be used to confirm the candidate’s interest in the position, verify they have the technical skills necessary for the position, form an initial opinion about if they will be a good culture fit, and understand the candidate’s salary expectations.

This is not the time for a deep dive, but an opportunity to make an initial determination on if it will be worthwhile for you to invest additional time interviewing them.

Use structured interview questions so you can easily evaluate all candidates you screen against the requirements of the job.

GMA + Integrity + Personality Tests

If the candidate passes the screening round, then we send them three assessments to take online: GMA, integrity, and personality. Our goal is to have a quantifiable measure of their problem-solving ability (which encompasses general intelligence and their ability to learn), how risky of a hire they might be, and if their personality is a match for the position (i.e., we want developers who are conscientious). Facet has established benchmarks for what results automatically move a candidate on to the next round of interviews, what results merit more discussion in the hiring team, and what results automatically disqualify a candidate.

There are many great off-the-shelf options available. A good rule of thumb is that the three tests combined should not take the candidate longer than an hour to complete.

Every candidate takes these tests so we can easily evaluate their results and see how they compare to other candidates and to the requirements of the job.

Man with headphones on sitting in front of a laptop.

Job Knowledge Interview

Job knowledge interviews are an important piece to our process because they work no matter what level we are hiring for. They are great for entry level positions where the candidate only has their education or training to rely on, or for more experienced candidates. The questions you use for your job knowledge interviews should be relevant to the level and technical skills you are hiring for and should be structured—meaning you need a set list and scorecard to ask and evaluate every candidate the same.

When hiring developers, we like to do two rounds of job knowledge interviews with two different members of our team (usually our CEO, who is a developer, and our principal software engineer). These interviews are scheduled back-to-back for 60 minutes each, and are followed immediately by the role, culture, and mission alignment interview.

Role, Culture, and Mission Alignment Interview

The final piece of the puzzle, after determining if the candidate has the knowledge and skills to excel in the job, is to ensure that the candidate will be a good fit at your company. This final interview should assess if the candidate’s personal values and beliefs align with those of their potential role and your company. Don’t get confused and think that culture refers to how much PTO you can give or what type of hybrid work schedule you can offer them. Instead, think of this interview as a compatibility interview. Will this candidate be an asset in helping your company grow and achieve its mission?

This interview should be no more than an hour and, when possible, conducted by an individual who has not yet been part of the interview process, to prevent bias, and who is deeply invested in maintaining a positive company culture, like the COO or head of HR. This interview should also be structured, although there may be times in this interview when it is appropriate to invite the candidate to ask some questions about your company’s culture and mission.

What’s missing and why

You may notice that we didn’t include coding tests or brainteasers like Leetcode. They don’t significantly increase the predictive validity or test for abilities or qualities that we haven’t already measured. Additionally, developers don’t like them. And we want a hiring process that developers are motivated to complete.

We also don’t ask subjective questions like, “Would I want to grab a beer with this person?” Questions like these introduce bias to the hiring process. And anyway, what do your personal feelings about if the candidate would be a good friend matter for their job performance? You aren’t paying them to be your friend. You are paying them to get work done.

We don’t let interests or hobbies take priority when hiring developers. Instead, we focus on structured interview questions about their job knowledge and the results of their GMA test to determine if they could learn quickly to fill in any gaps in their knowledge.

Additional reading: 15 Fallacies Hiring Managers Believe

Why this process works

Facet’s hiring process allows us to hire efficiently and effectively. Our entire process can be completed in 4-5 hours, in less than a week. And because it utilizes high-validity selection methods that consider the candidate experience, this process is more efficient and accurate than 8 hours of interviews and an 8-hour take home project.

Designing Your Own Process

You are welcome to use (or tweak!) Facet’s process, but if you want to design your own, follow these steps:

  1. Determine what qualities and characteristics you want to evaluate.
  2. Select an off-the-shelf GMA test.
  3. Establish the interview process framework: how many interview stages, how long each interview will be, what order your interviews will follow, the length of time between each interview, and who will evaluate candidates in each interview.
  4. Build out each interview stage by determining which additional selection methods you will use and what questions you will ask to evaluate the desired qualities and characteristics.
  5. Establish metrics and criteria for evaluating responses and determining if a candidate moves to the next stage in the interview process.

As you make these decisions, balance the candidate experience with the capabilities of your hiring team and the use of high-validity selection methods.

If you implement a process like this, you'll see greater cost savings, beat out more competitors, and improve the quality of your hires. Remember the goal—to make a good hire confidently. When you use data-backed selection methods, you can be confident. When you are confident, you can move quickly to hire the top technical talent.


Need help effectively hiring technical talent? Facet can coach you through the process of developing a scientific hiring process and supply you with qualified candidates for your tech roles.

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