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silent failures

2 articles about "silent failures".

Input Validationsilent failuresTestingPythonActuarial開源chainladder

A Validation Check One Line Too Late Doesn't Raise, It Becomes Decoration: Four Silent Failures in chainladder's predict

predict in the actuarial library chainladder-python still returns a result for four kinds of mismatched input: 775 rows go in and 643 come out, 6 rows go in and 775 come out, one row's pattern applied to another row comes out 38% short, and a paid pattern applied to incurred data overstates by 52%, all without an error message. This post unpacks two input-validation lessons from our fix, PR #1310: legitimate and dangerous looseness look identical in the data, so look for a marker the system writes itself; and a check placed after the line that rewrites its input does not raise, it goes blind in exactly the case it most needs to see.

· 15 min read
reliabilitymonitoringsilent failures自動化observability

The Dashboard Said Running. The Service Had Done Nothing All Night: Four Silent Failures in Automation Monitoring

A running flag that was always false, a heartbeat that measured presence instead of work, alert dedup that muted a real outage, and an auto-stop with no auto-resume. Four real bugs from our automation fleet, each with the broken check, why it lied, and the check that replaced it.

· 11 min read