Software Engineer & Writer
I'm a developer based in Berlin. I work on distributed systems by day and write about technology, craft, and the occasional odd problem I can't stop thinking about.
Read recent postsRecent Writing
Why Your Service Mesh Is Lying to You About Latency
P99 looks fine. Users are complaining. Here's where the numbers hide the truth and how to actually measure what matters.
The Underrated Skill of Deleting Code
Every experienced engineer eventually learns that the best pull request is often the one with more red lines than green ones.
Postgres Connection Pooling: A Story of Gradual Ruin
How we went from "it works fine" to "nothing works at all" in three painfully instructive steps, and what we rebuilt afterward.
On Abstractions That Outlive Their Usefulness
Every abstraction starts as a solution. At some point, many of them quietly become the problem. Recognising that moment is most of the work.
Six Months with Neovim After a Decade of VS Code
Not a conversion story. Just an honest account of what changed, what didn't, and what I stopped caring about.
Selected Projects
Fenix
A lightweight log aggregation daemon that speaks Prometheus natively. Handles 40k events/sec on a $5 VPS.
Radix Notes
A plain-text note-taking tool that stores everything as Markdown and syncs via any file system or object store.
Typemark
A CLI that converts annotated TypeScript interfaces to human-readable API documentation with zero config.
Blockform
Schema-first form builder for React. Define once, render anywhere, validate consistently across client and server.
About
I'm Alex Mercer, a software engineer with about nine years of experience building backend systems and developer tooling. Currently I'm working at a logistics startup in Berlin where we move a surprisingly large amount of data around in real time.
Before that I spent a few years at a payments company, which taught me more about failure modes and race conditions than any book ever could.
I started this blog because I kept writing long Slack messages that deserved more than 24 hours of shelf life. Most posts are technical. Some are not. I try to be honest about what I don't know.
Outside work: trail running, sourdough bread with varying results, and a long-running project to finally understand compilers.
Berlin, Germany
Get in Touch
I'm generally reachable by email. I'm also on GitHub if you want to look at code or file an issue on something I built.