Failure Lab · interactive engineering post‑mortems
Make the call the engineers made, then see what the record says happened.
- Decide with the evidence the team had at the time.
- Run a simplified model of the system.
- Read what the official record found, passage by passage.
Scenarios
No sign-up, no tracking. Each model runs entirely in your browser.
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1996Flight software
Ariane 5 Flight 501
You are on the inertial-reference software team with an 80% processor budget. Seven conversions could overflow. Ariane 4 flight evidence says which ones matter. Choose what to protect, and whether proven behaviour keeps running after lift-off.
- Decisions
- A protection budget and one heritage setting
- Record
- ESA/CNES Inquiry Board report, 19 July 1996
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2012Trading deployment
Knight Capital, 1 August
New order-router code has to be live before the market opens. Choose how it ships to the servers, how it is switched on and what happens to old code. Then the opening bell rings, and you make one more call.
- Decisions
- Three before the open, one during it
- Record
- U.S. SEC order, Exchange Act Release No. 70694, 16 October 2013
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2017Database recovery
GitLab, 31 January
Replication has stalled. Choose the cleanup host, check recovery readiness and select a fallback copy. Then compare your modelled result with the postmortem.
- Decisions
- Two before cleanup, one during recovery
- Record
- GitLab postmortem, 10 February 2017