Programming bootcamps seem to make an impossible claim. Instead of spending four years in university, they say, you can learn how to be a software engineer in a three month program. On the face of it, this sounds more like an ad for Trump University than a plausible educational model.

But this is not what we’ve found at Triplebyte. We do interviews with engineers, and match them with startups where they’ll be a good fit. Companies vary widely in what skills they look for, and by mapping these differences, we’re able to help engineers pass more interviews and find jobs they would not have found on their own. Over the last year, we’ve worked with about 100 bootcamp grads, and many have gone on to get jobs at great companies. We do our interviews blind, without knowing a candidate's background, and we regularly get through an interview and give a candidate very positive scores, only to be surprised at the end when we learn that the candidate has only been programming for 6 months.

Bootcamp grads are junior programmers. They have a lot to learn, and represent an investment on the part of a company that hires them. That said, this is also true of recent college graduates. We’ve found bootcamp grads as a group to be better than college grads at web programming and writing clean, modular code, and worse at algorithms and understanding how computers work. All in all, we’ve had roughly equivalent success working with the two groups.

In this post, I'm going to try to shed some light on how this can be true. I’ll dig more into the differences that we see between the two groups, and hopefully explain how some people can become competitive junior programmers in under a year.

The Analysis

Our technical interview at Triplebyte is about two and a half hours long, and is broken into four main parts, focusing on practical programming, web architecture, low-level system understanding, and algorithmic understanding. Not every engineer completes every question (we let programmers focus on their strengths), but the process gives us a good measure of the relative strengths of each engineer in each of these areas.

To get a better idea of how bootcamp grads and college grads compare, I graphed the two groups’ average performance in each of these areas. The y axis is the score on each problem (where 1 = strong no, 2 = weak no, 3 = weak yes, 4 = strong yes). For reference, I also included the entire population of applicants, and also all engineers who pass our interview.

The first thing to note about this graph is that bootcamp grads do as well as or better than college grads on practical programming and web system design, and do worse on algorithms and low-level systems. Our practical programming questions are not easy. They require understanding a problem, coming up with abstraction to solve the problem, and rendering this in code. If anything, our practical programming questions require more on-the-spot thinking than our algorithm problems do. They do not, however, require academic CS or math, or any specific knowledge. This is the crux of the issue. Bootcamp grads match or beat college grads on practical skills, and lose on deep knowledge.

A similar pattern holds on the design questions. Bootcamp grads do better on web questions involving web servers, databases and load balancers. College grads do better on low-level design questions involving bit/bytes, threading, memory allocation, and understanding how a computer actually works.

Triplebyte sees a biased sample of both bootcamp grads and college grads. We do background-blind screening via an online programming test, and only interview engineers who pass this test. Thus we have no way to know what percentage of bootcamp grads and college grads fail early in our process, and the graph above reflects only people who pass our test. Still, a significant number of bootcamp grads pass our test and go on to do as well as college grads on our interviews.

I want to specifically draw attention to the performance of college grads on algorithm problems. They are not only better than bootcamp grads, they are a lot better. They are significantly better than the average programmer making it to our interview (most of whom have 2+ years of experience), and almost as good at the average engineers who we pass. This is interesting. It backs up the assertion that algorithm skills are not used on the job by most programmers, and atrophy over time.

How is this possible?

Our data aside, it still just seems hard to believe that 3 months can compete with a 4-year university degree. The time scales just seem off. The first thing to note is that the difference in instructional time is not as large as it seems. Bootcamps, are intense. Students complete 8 hours of work daily, and many stay late and work on the weekends (one popular bootcamp runs 6 days per week). TAs are working with the students during this entire time. What bootcamps lack in duration they perhaps make up in intensity.

The second point is that bootcamps teach practical skills. Traditional CS programmers spend significant amounts of time on concepts like NP-completeness and programming in Scheme. Now, I in no sense mean to belittle this material. I love academic CS (and the Cook–Levin theorem). It’s beautiful, fascinating stuff, and I got a lot out of learning it. But it is not directly applicable to what most programmers do most of the time. Bootcamps are able to show outsized results by relentlessly focusing on practical skills. Bootcamp TAs continually critique each student's coding style. They teach testing. They teach their students how to use their editors. How to use an editor is something that a traditional CS degree program would never think of teaching.

This does not leave bootcamp grads equivalently skilled to university grads. If you want to do hard algorithmic or low-level programming, you’re still better served by a traditional CS eduction. But it does leave the best of them surprisingly competitive for many entry-level development positions.

Conclusion

There are two ways to interpret the results in this blog post. One way is to say that bootcamps are window dressing. They teach inexperienced programers what they need to know to look like good programmers, but skimp on the heart of the discipline. However, I think this view is too cynical. The other way to view this post is as evidence that bootcamps focus on totally different areas than CS programs. They focus intensely on the practical skills required to be a productive programmer. These are skills that CS programs expect students to pick up around the edges of their course work. By being this pragmatic and giving students an intense workload, bootcamps are able to match the practical skills of CS grads.

Bootcamp grads don’t make sense for all companies. Just like recent college grads, they are an investment for a company that hires them. They have much to learn. And they are clearly worse at algorithms and low level systems than engineers with academic training. A database or self-driving car company should probably stick to folks with CS degrees. But the significant majority of companies need programers to solve practical problems on the web. On this axis, we’ve found bootcamp grads totally competitive.

Triplebyte is one year old. In that time, we’ve both placed bootcamp grads at top companies, and also watched them grow. We’ve watched them learn some of the CS skills that they lack on graduation. We’ve watched them learn about large-scale production systems. We’ve watched them take on leadership positions. It’s really incredible how quickly and how well the best bootcamp grads learn. It’s been a pleasure to work with them, and we’ll definitely keep working with bootcamp grads.

If you’re a bootcamp grad (or a college grad, or anyone else), and are interested in a way to find companies where you’re a strong technical match, give our process a try. I'm also interested in your thoughts on this post! Send me an email at ammon@triplebyte.com.