Backend engineer — Python, FastAPI, PostgreSQL. CS at BITS Pilani, working toward AI systems. I post what I'm building, what broke, and what I learned fixing it. subhambhattacharya.comhttps://bsky.app/profile/subham-hq.bsky.socialhttps://bsky.app/profile/subham-hq.bsky.social/post/3mslmic3mu22gAn error status is not an error. Building a link checker, the instinct is raise_for_status(). But a 404 is the thing I'm looking for. Only transport failures raise — DNS, refused, timeout. Those mean the request never happened. A 404 means it happened perfectly and the answer is bad news. #python08 Aug 2026 17:40 +0000at://did:plc:utglnjohluybfqkryehbgp2d/app.bsky.feed.post/3mslmic3mu22ghttps://bsky.app/profile/subham-hq.bsky.social/post/3mslmct4kwk2gThe most expensive bugs don't raise. urlsplit("example.com").hostname returns None. So my crawler's same-host check rejected every link, finished cleanly, exit 0, and reported on zero pages. Nothing to catch. Nothing in the logs. Just a confident answer that was wrong. #python #backend #asyncio08 Aug 2026 17:37 +0000at://did:plc:utglnjohluybfqkryehbgp2d/app.bsky.feed.post/3mslmct4kwk2g