Working with legacy code video series. Episode 1 – James

Watch part one of our new video series about working with legacy code, and projects you’re not familiar with.

Welcome to our video series!

There are a lot of videos online of software engineers building things from scratch, and a lot of videos of engineers solving challenges or working with code that they’re familiar with.

These are both incredibly useful but sometimes it can look a bit like magic. How do they know exactly where they will be adding code? In real life, software engineers often work with code we’ve never seen before that someone else wrote which means we need to go through a process of understanding the current codebase (legacy code) and working out where we need to make the changes before adding the code that achieves this.

In this video series, we’ll be putting experienced software engineers in front of open source projects that they’ve never seen before and asking them to add a feature. We don’t care about the code, we’re more interested in how they approach the problem and the steps they go through to solve it.

In this episode:

• James will be our experienced engineer. James is an engineering lead and has worked with Rails and React at Simply Business and previous companies.
• We’ll be using an open sourced clone of the blog ‘Medium’ called Stories.

Key takeaways from the episode

• Before even thinking about design, James wanted to dive into the codebase and find the code that created the preview form (that we wanted to add the button to) and also the publish button so that his design decisions would be based off how the code currently works, rather than speculating.
• To find the code, he started with the front-end and used the inspect element feature in the browser to identify elements on the form & button (e.g. finding the id of an element) which he then used to search the codebase and find the corresponding code.
• A tactic he used quite often was to just think of places he thought the code would make sense to be (header, navigation, menu) and search for those files. This resulted in some quick wins.