Show HN: I rewrote my notepad calculator as a local-first app with CRDT syncing

Hacker News (score: 32)
Found: June 30, 2025
ID: 80

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Show HN: I rewrote my notepad calculator as a local-first app with CRDT syncing I launched NumPad v1 on here a few years ago, and back then it wasn't much more than a thin CodeMirror wrapper around the calculator engine I'd written.

Now I've rewritten it as a PWA that supports multiple documents, persists them to IndexedDB, and has a syncing service for paying customers. Syncing is handled by Automerge[1] under the hood, which should make it relatively easy to get document sharing working too.

[1] https://automerge.org/

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