pricing
Priced per seat, like the infrastructure it replaces.
Free to self-host, forever. Pay only when you want the hosted bus and the arbiter reasoning across your team.
Open core
Free forever, MIT
Self-host the whole protocol on your own bus. Never crippled.
- The CLI, four Claude Code hooks, and MCP server
- Single-team bus, contract registry, and ledger
- The deterministic fence and the five skills
- The Opus 4.8 arbiter (bring your own key)
- Git-native team layer and read-only tower
- Community support
Most popular
Datum Cloud
$20 / developer / month
Hosted coordination, so a team skips the VM and the tunnel.
- Everything in Open core
- Hosted multi-tenant bus, no VM or tunnel
- Team-management dashboard and workspaces
- Pooled arbiter, we pay the model cost
- Analytics: drift trends and fence stats
- Email support
Enterprise
Custom
For orgs with security and scale requirements.
- Everything in Datum Cloud
- SSO and SCIM
- Retention, audit log, and data residency
- Self-hosted or VPC deployment
- Priority support and SLAs
Seats are billed for active developers only. The whole protocol stays open and MIT whatever you pay.
questions
Before you ask
What is actually open source?
The whole protocol. The CLI, the four hooks, the MCP server, the single-team bus plus registry plus fence, the arbiter (bring your own Anthropic key), the git-native team layer, and the five Claude Code skills are all MIT and self-hostable, forever. The core is never crippled. Datum Cloud is the hosted convenience on top, built on the published datum-core package, so the same coordination core runs self-hosted and in Cloud.
Then what does Datum Cloud add?
The parts a team cannot easily self-host: a hosted multi-tenant bus (no VM or tunnel), a team-management dashboard, a pooled arbiter where we pay the model cost instead of your own key, plus SSO, retention and audit, and analytics. Per seat, billed for active developers only.
Does it work with tools other than Claude Code?
Claude Code today. The registry and the event protocol are agent-agnostic by design, so Cursor and Codex are next on the list rather than a rewrite.
Where does the arbiter run?
Off the critical path, server-side, so it never makes an agent wait. Correctness comes from the deterministic fence on each machine, and the fence fires even with the arbiter disabled. The model adds judgment after the fact, never in front of your keystrokes.
What happens if datum goes down?
The hook fails open and your agents keep working. You lose coordination for the length of the outage, never the ability to write. Nothing about datum can brick an engineer mid-task.