ALTER TABLE on 30 million rows blocks writes for 40 minutes, and checkout writes to that table. A shadow table, triggers, and a backfill paced by replication lag.
A certificate is bought once, installed once, and the diary entry belongs to whoever did it — which survives about as long as their current job. Two years…
A cache goes in, the page gets faster, and that is usually where the measurement stops. Redis has been counting every lookup since it started and will tell…
A query answering in 20 ms locally and timing out on four million rows. An anonymised data subset that keeps the query plan honest, and the mail, cron…
Three developers, three PHP patch versions and a bug that existed on one of them. A Vagrantfile, a playbook for everything inside it, and what the rebuild costs.