Local-first architecture is a way of building software where the user's device keeps a real working copy of useful data.

In this episode, Satish uses a simple real-life example first, then turns the idea into a practical technical mental model for engineers and curious builders.

In Simple Terms with Satish: daily tech trends explained simply, with enough technical depth for builders.

Production note: This episode uses authorized synthetic narration based on Satish's own voice. The topic, script, and final editorial approval are by Satish.

Engineer notes:

Exact technical references:

- SQLite says it is likely used more than all other database engines combined and appears across phones, desktops, browsers, and many applications; its page was last updated on April 21, 2026.

- SQLite documents ACID transactions that remain atomic and durable through crashes or power failure.

- MDN describes the origin private file system as widely available, private to a page origin, optimized for performance, and usable from web workers.

- Zero describes reads and writes hitting a local normalized client datastore first, then syncing with the server in the background.

- Electric Sync describes a Postgres read-path sync engine that syncs subsets of data into local apps using shapes, and its shape guide says production apps should request shapes through a backend API for authorization and security.

- Automerge describes local copies that can update offline, sync later, and automatically merge concurrent changes.

Sources:

- https://www.sqlite.org/mostdeployed.html

- https://www.sqlite.org/transactional.html

- https://developer.mozilla.org/en-US/docs/Web/API/File_System_API/Origin_private_file_system

- https://zero.rocicorp.dev/docs/introduction

- https://electric.ax/docs/sync/

- https://electric.ax/docs/sync/guides/shapes

- https://automerge.org/docs/hello/