Running only a single instance of a process

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...

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...

Sometimes, when writing tests in Pytest, I find myself using fixtures that the test function/method doesn’t directly reference. Instead, Pytest runs the fixture, and the test function implicitly leverages its side effects. For example: import os from collections.abc import Iterator from unittest.mock import Mock, patch import pytest # Define an...

Although I’ve been using Python 3.12 in production for nearly a year, one neat feature in the typing module that escaped me was the @override decorator. Proposed in PEP-6981, it’s been hanging out in typing_extensions for a while. This is one of those small features you either don’t care about or get totally psyched over. I’m definitely in the...