Most durability demos are “trust me”: a blog post, a benchmark chart, or a unit test.

This is a live sandbox that tries to make durability auditable.

Every visitor gets:

a dedicated Docker container (no shared state with other visitors)

a dedicated persistent volume mounted at /data

Click “Run double proof” and it does:

Produce N events

Hard-kill the process with a real SIGKILL (docker kill -s KILL)

Restart the container (docker start)

Consume from offset=0 → should return N (no loss)

Commit offsets (Ayder commits “last processed”; resume starts at committed+1)

Consume again with the same group → should return 0 (no duplicates)

The UI shows pass/fail, but also exposes the raw proof JSON and “Docker Forensics” (inspect + docker events + logs tail) so you can verify the kill/die/replay yourself.

I’m curious: what other failure modes would you want a demo like this to cover (disk full, host reboot, partial writes, etc.)?