Occasional notes on building and operating backend systems in Elixir and Ruby — not a high-frequency blog, but a place for ideas worth keeping.
Headless Chrome kept getting OOM-killed on our smallest VM just to print a two-page report. We replaced it with a pure-Elixir PDF library — 41x smaller files, millisecond renders, no browser in the image, and five features contributed upstream along the way.
A token-bucket rate limiter in Elixir (GenServer) and Ruby (concurrent-ruby): same mailbox pattern, different runtime, with honest notes on threads, OS processes, and the BEAM.
How we engineer seamless, high-bandwidth eSIM packages by automating daily plan rotation, without the user ever noticing a swap.
A working system is not always a healthy one. On GenStage, JPEG snapshots, and why simplification is an optimization — not a downgrade.