Local-first software: You own your data, in spite of the cloud

Source: Ink & Switch Authors: Martin Kleppmann, Adam Wiggins, Peter van Hardenberg, Mark McGranaghan Date: 2019-04

Core idea

Local-first software argues that collaborative systems should keep the primary copy of data on users’ own devices while still supporting real-time collaboration, multi-device sync, offline work, and long-term user ownership.

Key claims

• Collaboration does not require surrendering the source of truth to one cloud service.
• Fast local interaction, offline operation, and durable data ownership can coexist with multiplayer editing.
• Replication and sync should serve shared work rather than replace user sovereignty.

Harness takeaway

A serious multiplayer harness should be local-first: each human or agent keeps a useful local harness with its own state, while shared workspaces, traces, and plans replicate outward instead of living only in a central service.