For the past decade, web apps moved everything into the cloud. You type a character, a network packet travels to AWS US-East-1, writes to a database, and returns to confirm your keystroke.
When it works, it feels like magic. When your Wi-Fi flickers, your application freezes, shows a spinner, or loses your unsaved draft.
What is Local-First?
Local-first software flips the paradigm:
- **Primary state on your device:** Reads and writes happen instantly against local storage (SQLite, IndexedDB, local files).
- **Background synchronization:** Changes sync asynchronously via CRDTs or delta streams when a connection is available.
- **Ownership:** Your data lives on your disk in standard formats. If the SaaS provider shuts down tomorrow, your files still open.
The Developer Shift
With tools like ElectricSQL, Replicache, and SQLite compiled to WASM in the browser, building local-first web applications is becoming practical for everyday developers.
It's better for performance, better for offline resilience, and vastly better for user privacy.