Reading Source Code with Daniel Colson

Daniel Colson joins Andrew and Julie to discuss getting better at reading source code. He explains why reading source code can be beneficial and encourages trusting your curiosity when it comes to understanding code. He dives into Ruby source code and offers some tips on performance testing. Lastly, he talks about his new library for profiling FactoryBot and the idea of a flipped classroom. Download this episode today!

[00:45] Daniel Colson is our guest today and gives a brief introduction. He is also a FactoryBot maintainer and explains what it is.
[02:40] Andrew is curious about the relation to Music majors and programming and Daniel has some ideas on it.
[03:20] How much of your time is spent reading code? Daniel talks about the different types of code programmers often have to read and the benefits that come along with it. Andrew explains why he reads a lot of source code and how it made him better at code review.
[06:30] Do you copy and paste code without always understanding it fully? You aren't alone! Daniel has some suggestions for trusting your curiosity and how he likes to read gem source code and how the tests can provide lots of clues. 
[13:38] Daniel has been reading the Ruby source code and dives into the why and his journey into learning C.
[20:20] How do we test the performance of code? Daniel suggests using benchmark-ips for Ruby code and why evaluating performance is important. 
[23:10] Julie asks if Ruby Under a Microscope would be a good book for juniors to read. 
[25:40] Daniel believes in a concept called "flipped classroom", which he explains and how it applies to learning programming. He also explains how he would prefer to give more interactive conference talks, which Julie and Andrew both encourage.
[29:20] Daniel has a new library for profiling FactoryBot that you will definitely want to check out!


Special thanks to Andy Croll for personally sponsoring this episode. Be sure to check out and for nice, free community resources for newer devs!

Daniel on GitHub
Ruby Under a Microscope

Creators and Guests

Andrew Mason
Andrew Mason
Senior Product Developer at Podia, co-host of the Remote Ruby podcast, and co-editor of the Ruby Radar newsletter
Julie J
Julie J
Software developer at Codecademy
Reading Source Code with Daniel Colson
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