Show HN: Tech Event Bingo – Track Events in Tech on a Bingo Card

With shopify buying TailwindCSS, I thought, "hey, I definetly had this on my tech bingo card."

So then I thought it'd be fun to build an app to generate these.

Put in your X handle (optional), get a card with a permanent URL, download it as a PNG. No signup, no cookies beyond the admin one nobody but me uses.

How it's built, since that's the part HN actually cares about: one Cloudflare Worker with Hono, D1 for storage, Tailwind v4, and workers-og (Satori + resvg) for the PNGs. The PNG rendering was the only hard part. Satori only speaks a subset of flexbox, so the HTML card and the image card are two separate renderers reading from one theme file so they can't drift. Cold renders take a few seconds, longer than social crawlers wait, so PNGs are pre-rendered at card creation, stored as blobs in D1, and cached at the edge.

The 120ish squares are hand-written. There's an admin page where Claude drafts new ones and I approve or reject them one at a time. Roughly a third of its drafts survive.

Happy to hear which squares you'd add. "Cloudflare outage breaks the web" is already on there, in case you're wondering whether this site is exempt.