Hierarchical rate limiting with Redis sorted sets

I came across a weird shell syntax today—dynamic shell variables. It lets you dynamically construct and access variable names in Bash scripts, which I haven’t encountered in any of the mainstream languages I juggle for work. In an actual programming language, you’d usually use a hashmap to achieve the same effect, but directly templating variable...

One of my 2025 resolutions is doing things that don’t scale and doing them faster without overthinking. The idea is to focus on doing more while worrying less about scalability and sustainability in the things I do outside of work. With that in mind, I’ve been thinking for a while about tracking some of my out-of-band activities on this blog. The...

I’ve been having a ton of fun fiddling with Tailscale1 over the past few days. While setting it up on a server, I came across this shell script2 that configures the ufw firewall on Linux to ensure direct communication across different nodes in my tailnet. It has the following block of code that I found interesting (added comments for clarity):...

People love single-method interfaces (SMIs) in Go. They’re simple to implement and easy to reason about. The standard library is packed with SMIs like io.Reader, io.Writer, io.Closer, io.Seeker, and more. One cool thing about SMIs is that you don’t always need to create a full-blown struct with a method to satisfy the interface. You can define a...

Setting up SSH access to a new VM usually follows the same routine: generate a key pair, copy it to the VM, tweak some configs, confirm the host’s identity, and maybe set up an agent to avoid typing passphrases all day. Tools like cloud-init and Ansible handle most of the setup for me now, so I rarely think about it. But I realized I don’t fully...