How to Test the Skills of a Developer

Rarely is a developer responsible for recruiting a developer.  Instead the job falls to an HR department or a hiring manager that may not be familiar with software development at all.  Which bodes the question – how do you test the coding skills of a candidate when you don’t code yourself?  Even with references and a decent understanding of the technologies at play, it is nearly impossible to be sure of the true ability of a developer until they actually begin a project.

Enter online platforms designed to assess tech candidates’ skills.

There are quite a few out there—Codility, Devskiller and CodinGame to name a few, all with tests that will help a non-techy understand the skill-level of a developer candidate. But if you aren’t ready to sign up to such a platform, most of them produce an annual report based on findings gathered from the tests taken, giving you free insight into how to source the most reliable, proficient developers.

Devskiller for example, recently published its Devskiller Technical Hiring & Skills Report 2019, based on over 112,000 coding tests taken on their platform. It has useful interactive maps showing which countries hire the most tech talent, and which export it, as well as some stats on top technologies hired for.  But in case you don’t have time to look at the actual report, we have compiled the insights we found most interesting for you here:

Insight #1: 70% of companies are searching for a JavaScript developer

Looking at the technologies tested by most companies, it is surprising to see Java isn’t the most popular. Instead, 70% of the companies tested are in search of a JavaScript developer.  Java on the other hand, was third on the list. SLQ came in second place, showing that database skills are important for both back and front-end developers. And HTML/CSS came in fourth, with .NET/C# fifth.

Insight #2 Most developers will get a database technical skills assessment, regardless of their main focus

Once again, JavaScript is the leading technology here too. In looking at the 8 top technologies tested together, 5 of them involve JavaScript in some way, shape or form. Take for example JavaScript and CSS and HTML - the fundamentals of a solid front-end stack. But JavaScript is also regularly paired with .NET, PHP and Java, thus showing its importance in both front-end and back-end roles.  SQL is the next most co-tested stack, with 4 mentions. 

Insight #3: Candidates wait on average 2.88 days to take a coding test

Developers prefer to do take-home coding tests during the week and save their weekends for themselves. 

This is reflected in the fact that:

  1. Tests sent on Tuesday get the fastest response

  2. Tests sent on Wednesday get the slowest response

  3. The average turn around is 2.88 days

As a recruiter, this gives you valuable insight into how coders prioritize coding tests for a new position. If you send coding tests early in the week, you can quickly push through talented developers.

Insight #4: The US recruits internationally while also being a major source of international technical hiring

You may be surprised to know that countries that produce and export coding talent also hire talent from abroad. For example, India makes up over 25% of the talent that’s picked up by international companies. The US comes in second thanks to the sheer volume of tech talent it creates. Germany, Brazil, and Argentina make up the top 5. What is interesting within this data, is that large candidate countries like the US also recruit from abroad quite a lot.

For example, the US also hires from the other top 5 candidate countries like India and Germany.  Interestingly however, India doesn’t recruit from anyone else in the top 10 sources of exported talent. 

Insight #5: New Zealand developers score the highest (54.66%) on coding tests

Perhaps you are interested in which countries produce the highest scoring developers? New Zealand developers score the highest at 54.66%.  When you consider that most candidates are screened out and that the average score is 40.71%, this is quite an achievement. New Zealand was followed by the Netherlands.

Online coding tests can be a big help when trying to ascertain the true skill set of a developer, but they won’t ever tell the whole story.  Understanding how a candidate works within a team, their sector experience and the type of environment they thrive in accounts for a lot in ensuring a successful hire. So while these online assessments certainly have their place, and the data gleaned from their reports can prove incredibly useful, they can’t replace an experienced tech recruiter’s insight, market understanding and trusted network.

About Oliver Parks

Oliver Parks Consulting offers search-based recruitment solutions to the technology sector, specialising in the ERP, CRM, CMS, ECM, BI and Open Source Technology spaces. The firm’s multilingual consultants operate in narrowly-defined niche market segments, enabling them to gain extensive knowledge of the people and companies operating in each technology.  Oliver Parks has a proven track-record with more than 100,000 candidates worldwide and more than 300 clients globally.