Local-first software and why it matters
The case for keeping data on device. Performance, privacy, and the surprisingly better developer experience.
Most apps today work like this: your data lives on a server, and the app is a window to access it. Local-first flips this: your data lives on your device, and sync is optional.
I’ve been building local-first apps for the past year. Here’s why I think this approach matters.
Performance you can feel
When data is local, there’s no loading spinner. No “waiting for server” state. Actions feel instant because they are instant.
Users notice this. They might not articulate it, but they feel the difference between an app that responds immediately and one that doesn’t.
Works offline by default
Offline support isn’t an edge case you handle—it’s the default behavior. Network becomes an optimization, not a requirement.
This changes how you think about error states. No network? Fine, keep working. Network comes back? Sync in the background.
Privacy as a feature
When data stays on device, you don’t need to worry about server breaches. You don’t need to write privacy policies about data you never collect.
The tradeoffs
Sync is hard. Conflict resolution is genuinely complex. You’ll need to think about CRDTs or operational transforms or similar approaches.
Some features need a server. Real-time collaboration, shared workspaces, notifications—these require coordination that local-first makes harder.
Worth exploring
Local-first isn’t right for everything. But for tools where data is personal and performance matters, it’s worth considering.