Performance and scaling consultant who analyzes the full stack - frontend, backend and infrastructure - to generate more revenue and cut costs for businesses.
Remote • Available for monthly retainer and bespoke projects.
I was recently adding a bunch of files to a new Git repo, but I couldn't be sure if I was about to commit a 100MB file. The following bash command should print out a sorted list of unstaged files and their size, so you can check if
If you read my blog or follow me on Twitter you may have noticed I'm a huge fan of flamegraphs. I've previously written about how I use them to profile PHP and Node.js applications, and I help maintain rbspy, a Rust profiler for Ruby, which
Last October I made Upgrade your PHP [https://upgradeyourphp.com/], a site to let people know that PHP 5.6 and PHP 7.0 were about to reach their End of Life, and would no longer be officially supported. In the time since, I've been helping people upgrade
This post is a case study of how I profiled a Node.js application, and how using flamegraphs allowed me to make the boot time of Ghost 20% faster. I remember trying to profile Node.js many years ago and it was much harder than it is now. When researching
Earlier today I was looking at a couple of sites to see why they were much slower than I expected. I ran them through GTmetrix and saw the following in the waterfall tab. Straightaway I could see that this is the classic pattern produced by trying to load a bunch
I recently added support for Ruby 2.5.4, 2.5.5 and 2.6.0-2.6.3 to rbspy, the sampling profiler written in Rust. I have replaced the original Flamegraph library by Brendan Gregg with Inferno, a Rust port. I also updated and merged a PR for handling
A few days ago, the server running Nomad List [https://nomadlist.com] and Remote OK [https://remoteok.io] randomly went down. This is the timeline of what happened and how I fixed it. All times are in Korean Standard Time. 21:05 Pieter [https://twitter.com/levelsio] starts messaging me
A week or so ago, I saw the inferno [https://github.com/jonhoo/inferno] project mentioned on the Rust subreddit. It was a rewrite of the great FlameGraph [https://github.com/brendangregg/FlameGraph] library into Rust. All of the work was being livestreamed by Jon Gjengset [https://twitter.com/Jonhoo/
When a client asks me to take a look at their site, I start off by throwing it into a bunch of services to analyze the performance. One of my favorites is GTmetrix [https://gtmetrix.com] because it has a lot of useful metrics and visualizations. The most useful one
Towards the end of last year I made Cron Heatmap [https://cronheatmap.com], a website to visualize your cron jobs and help you find hotspots. The motivation from the project comes from my work over at Nomad List [https://nomadlist.com] and Remote OK [https://remoteok.io]. There are over