A local agent harness

Lay the keel.
Raise the ribs.

Keelson is a single-user agent harness. It wraps a coding agent with persistent state, deterministic YAML workflows, and a typed extension contract. The harness is the keel, the part that ships, and it is useful on its own. Ribs are the capabilities you bolt on for more.

Apache 2.0 · Beta · runs locally on Bun

FIG. 01 · THE FRAME A blueprint side elevation of a hull. The keelson beam is the harness; three brass frames rise from it, bolted to the beam, each labeled as a keelson-rib package. A midship section inset shows one rib bolted to the keelson. The CLI is the rudder, the browser SPA a surface, and a dashed superstructure (wheelhouse, mast, and rigging) marks structure still under construction.

Chat

Talk to the agent with every rib tool on tap.

Workflows

Deterministic runs as readable YAML.

Memory

Persistent, searchable, and governed.

Providers

Copilot, Claude, Codex, Pi. Swappable, no lock-in.

Surfaces

Ribs emit JSON; the app renders live boards.

Ribs

Capabilities ship as packages, not forks.

Where to start