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Bug Hunt @mukkoo

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@mukkoo

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dev.welaika.com @mukkoo

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@mukkoo

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debugging instinct @mukkoo

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@mukkoo

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@mukkoo I know how to fix it!

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@mukkoo

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debugging instinct @mukkoo debugging tools/xp

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recap no super heroes, no unicorns @mukkoo no instinct debugging tools and experience

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debugging patterns @mukkoo

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@mukkoo Containment, sometimes, takes priority over fix

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@mukkoo we work only with facts

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@mukkoo observable attributes

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@mukkoo isolation and reproduction

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@mukkoo fix it!

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recap observe @mukkoo choose tools and strategy fix it

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bugs taxonomy @mukkoo

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@mukkoo observable attributes i can reproduce it locally it seems to affect only one area #1

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@mukkoo bohrbug deterministic, highly
 reproducible #1

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@mukkoo bohrbug lives in the code
 LIKES hide them IN complex FUNCTIONS, CLASSES OR CONFIGURATIONS #1

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@mukkoo tools #1 factories fixtures local tests

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@mukkoo reproduction & resolution #1 replicate bug conditions locally test it write simplest solution refactoring for more readability

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@mukkoo bohrbug #1 FIxed

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@mukkoo observable attributes something that has always worked seems to have never worked #2

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@mukkoo schrödinbug looks like leaf #2

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@mukkoo schrödinbug pretend to be working code on close inspection reveal itself like a bug #2

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@mukkoo schrödinbug two types: - had never worked - works in a different way you think #2

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@mukkoo tools #2 LOGS to verify BISECT

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@mukkoo reproduction & resolution #2 REPRODUCE bugGED STATE locally AND IN TESTS ADD LOGS FIND When it was introduced WRITE TESTS AND FIX IT

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@mukkoo schrödinbug #2 FIxed

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@mukkoo observable attributes APPEARS NON DETERMINISTIC seems to DISAPPEAR WHEN OBSERVED #3

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@mukkoo heisenbug CAN YOU SEE IT? #3

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@mukkoo heisenbug lives in the code, debugging tools modify code and execution #3

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@mukkoo heisenbug or lives in the data and you can only see the bug on production #3

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@mukkoo tools #3 profiling and metrics FLAMEGRAPHS

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@mukkoo

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@mukkoo reproduction & resolution #3 use profiling to find it use real data to reproduce recreate the state in tests follow bohrbug instructions

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@mukkoo heisenberg #3 FIxed

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@mukkoo observable attributes everything is broken #4

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@mukkoo mandelbug random and
 Infinite reproduction #4

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@mukkoo mandelbug lives in your system #4

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@mukkoo tools #4 server tools DF -h

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@mukkoo reproduction & resolution #4 monitoring access to server restart, rotate or kill

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@mukkoo mandelbug #4 FIxed

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RECAP @mukkoo

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@mukkoo observe and classify

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@mukkoo reproduce and isolate

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@mukkoo test and fix it

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@mukkoo build your own toolkit

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Q&A thank you all @mukkoo