Blog

Notes from running CosmicIRC

Engineering write-ups from operating an independent IRC network — real bugs, real fixes, and occasionally an honest "we don't know yet."

The crash that survived every fix

A typo-tracking script kept crashing eggdrop with free(): invalid size. We fixed the obvious cause. It kept crashing. Here's the investigation, and why we eventually gave up rather than ship a guess.

Pin every package in your Dockerfile

Adding one package to a working Dockerfile triggered a SIGSEGV crash-loop in an unrelated library. The cause wasn't the new package — it was every package we never pinned.

Turning on a DNSBL uncovered a bigger bug

Adding spambot-blocklist checking to InspIRCd was supposed to be a quiet config change. It led us to discover every ban we'd ever set was memory-only and vanished on every restart.