notes

things that broke, and what I learned before they broke again, 5 so far

• Public IP, private IP, and the router in between2026-07-16Your devices share one public address through NAT, which is why 'what's my IP' reads the same everywhere and why nobody can reach your laptop directly.networkinginfra
• IPv4, IPv6, and why the old one won't die2026-07-16IPv4 ran out of addresses years ago, yet most of the internet still runs on it. Who hoarded the addresses, and how the cloud keeps handing them out.networkinginfra
• Buying a domain without the year-two surprise2026-07-16Where to actually buy a domain, why the sticker price is a trap, and which registrars charge the same every year.domainsweb
• Springs, not eases2026-07-11A five-line spring integrator makes motion feel hand-made, and it tells you exactly when to stop your rAF loop.animationux
• Don't run next build while next dev is running2026-07-11Both write to .next, so the build silently corrupts the dev server and you get manifest ENOENT errors or a blank 500.nextjstooling