Proof Summary
fast signal for HN readers: pass/fail + key numbers
No loss (found == expected)
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Second consume (same group) is zero
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restart
no loss
offset math
same-group zero
Raw Proof JSON (exact API response)
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Docker Forensics (inspect / events / logs tail)
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What this proves
• Dedicated container per visitor (no interference)
• Real SIGKILL via Docker
• Manual restart (docker start)
• Persistent volume stays mounted at /data
Proof flow:
1) Produce N messages to topic “events”
2) SIGKILL the process (no graceful shutdown)
3) Restart container
4) Consume from offset=0 → count=N, next_offset=N
5) Commit via /broker/commit (commits last processed = next_offset-1)
6) Consume again (offset omitted → resume from committed+1) → 0 messages
If you doubt: expand “Docker Forensics” and inspect kill/start/events/logs.
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