The Heirloom License — software that outlives its maker

How it works

While active

A normal paid product

Buy it, use it, run it. You can't resell it or build a competitor from it. Business as usual.

If abandoned

The dormancy trigger

No update and no support response for the dormancy window (default 12 months). Objective — no committee, no court.

Forever after

It Sunsets open

Full source published publicly under a strong copyleft license (default MPL-2.0). Irrevocable. The community keeps it alive.

Why it's different

Not a fixed date. Unlike the Business Source and Functional Source licenses, it converts on abandonment, not a calendar date — detected by a dead-man's switch.
Stays open for good. Copyleft on Sunset means nobody can re-privatize the abandoned code. Not MIT — the commons keeps growing.
Costs the developer nothing while they're active, and earns buyer trust on day one.
Self-serve. Pick three parameters, drop in the workflow, show the badge: HL-1.0-MPL2.0-12mo.

Adopt it

Add the license, set your Change License, dormancy window, and repo, install the reference dead-man's switch, and display the badge. Then add your app to the wall.

Adoption guide Plain-English summary See who uses it