I built buildprof (Github), an open-source tracing tool that shows where the time goes when you compile software on Linux. Here’s a realtime video of it profiling a clean build of ripgrep: Watch the buildprof demo Sometimes, builds are slow because there is simply a lot of code to compile. But more often than not,...

I’ve been using Opus 5 as my main coding for the last few days 1, and I noticed something odd: the code comments stopped using em-dashes; everything is double hyphens (--) now. Instead of going off a gut feeling, I decided to actually run some checks. agentsview indexes all my conversations into a SQLite database,...

PyTorch profiles are going to look much better in the next release of Perfetto. Last time, I explained how PyTorch’s profiler emits events that overlap in ways that are technically forbidden by the Chrome JSON Trace Event spec. As a result, Perfetto used to drop these events on the floor. In the last release we...

To get promoted as a software engineer in Big Tech, you generally need to show “ownership” of a product or area. This means being responsible for it and deciding what should happen over time. I often hear more junior engineers ask: “How can I demonstrate ownership when my manager hasn’t given me anything to own?”...

In Devtools must be open source1 (via), David Crawshaw makes the case that, because of coding agents, we’re now in an era where devtools will be personalized by individual users. Specifically, agents’ ability to jump into new codebases and build whatever we want means we’ll be hacking on the source of the devtools...

Codeberg, a Git code hosting platform, recently took a decision to prohibit projects that mostly consist of generative-AI-written code which has prompted concern and extensive discussion elsewhere. The decision does not surprise me, and I don’t mean that as a criticism. Codeberg has always presented itself as a...

Antirez, the creator of Redis, recently argued that expert programmers using AI should think of themselves as being Linus Torvalds. The key part of his analogy is this: Automatic programming, instead, in the hands of people that are expert technicians, or expert programmers, expert designers, expert software...

“How do you find problems worth working on?” a senior engineer I mentor asked me recently. He’s trying to make the jump to staff engineer and realized that the role isn’t just about doing the work he’s assigned. He also needs to get involved in figuring out what his team and org should be building. Someone else had...

Writing for the world is something which has ebbed and flowed for me over time. I’ve always liked sharing my thoughts, starting with websites all the way back when I was a kid. In times when I sustained it, I had various “blog”-like things for technical projects which would often veer into sharing personal beliefs...

Working with lots of changes in parallel on git can be painful. You end up juggling branches and commits, and running scary rebase -i commands that can leave your tree in a half-broken state if you so much as sneeze. jj, an alternative to git, gets discussed a lot these days (1, 2, 3, 4) and is often pitched as a...

We just released Perfetto v57 and I wanted to share the new things I’m most excited about. This is something I wanted to do for past releases but I just never quite got round to it. It’s also something I plan on doing more of going forward: there might even be dedicated pieces if I think the feature deserves it!...

When impressive performance gains do not matter is a very nice article covering some ways in which going after performance alone is not sufficient without considering the wider picture. It resonated a lot with how I think about performance. If there are multiple bottlenecks in the pipeline—and with these systems,...