Marcus' Blog

Don’t underestimate the value of digging into history to investigate some bugs

I’ve always been pretty good at debugging weird issues, with the usual toolkit of println and the debugger. So I never really looked at git much to figure out the history of a bug. But for some bugs it’s crucial.

I recently had an issue with my server where it was leaking... See more

Make debugging easier

There’s so many little tricks I’ve acquired over the years on making software easier to debug. If you don’t make any effort to make debugging easy, you’re going to spend unacceptable amounts of time debugging each issue, as your software gets more and more complex. You’ll be terrified to make changes because even a couple new ... See more

Bad code gives you feedback, perfect code doesn’t. Err on the side of writing bad code

It’s really easy to write terrible code. But it’s also really easy to write code that follows absolutely every best practice, which has been unit, integration, fuzz, and mutation-tested for good measure – your startup will just run out of money before you finish.... See more

When working on a team, you should usually ask the question

There’s a spectrum of “trying to figure out everything for yourself” to “bugging your coworkers with every little question”, and I think most people starting their careers are too far on the former side. There’s always someone around that has been in the codebase longer, or knows technolog... See more

If you can’t easily explain why something is difficult, then it’s incidental complexity, which is probably worth addressing

My favorite manager in my career had a habit of pressing me when I would claim something was difficult to implement. Often his response was something along the lines of “isn’t this just a matter of sending up X when we Y”, or ... See more

Try to solve bugs one layer deeper

Imagine you have a React component in a dashboard, that deals with a User object retrieved from state, of the currently logged in user. You see a bug report in Sentry, where user was null during render. You could add a quick if (!user) return null . Or you could investigate a bit more, and find that your logout fu... See more

Spending time sharpening the axe is almost always worth it

You’re going to be renaming things, going to type definitions, finding references, etc a lot ; you should be fast at this. You should know all the major shortcuts in your editor. You should be a confident and fast typist. You should know your OS well. You should be proficient in the shell. ... See more

Assess the trade-off you’re making between quality and pace, make sure it’s appropriate for your context

There’s always a trade-off between implementation speed and how confident you are about correctness. So you should ask yourself: how okay is it to ship bugs in my current context? If the answer to this doesn’t affect the way you work, you’re bei... See more