Détectives de la prod : résoudre l’enquête avant le crash

A presentation at Devfest Nantes 2025 in October 2025 in Nantes, France by Sébastien Ferrer

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git commit git push

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❝ ❞ ❝ to join the night/weekend on-call rotation 2 months later ❞

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Project A Project B Project C Project D Project E Project F

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Root Cause Analysis (RCA)

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What problem am I trying to solve?

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Load balancer

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Load balancer

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Load balancer

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Load balancer

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creating user: creating user: creating user:

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creating user: creating user: creating user:

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Users can no longer connect to the application The authentication system returns an error 500 The authentication service is unable to query the user database The authn service cannot establish a connection to the database

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Develop your applications as if you were going to maintain them. Because you are. ~ a cool colleague

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message: ” ” AND user_id:42

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28 days ago

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z

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