Fix a users service that returns 200 for everything.
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Write a SQL query that builds a per-customer revenue report from an orders database.
Find where a request diverges from the pipeline's intended flow and fix it.
Clean a single user profile text field before storing it.
Safely parse the search endpoint's query parameters.
Fix the response serializer's content type, envelope, and date handling.
Fix the catalog's pagination off-by-ones and boundary bugs.
Handle Timezones
easyFix the timeline so events are ordered by their actual moment, not their printed time.
Protect a shared get-or-create registry from a check-then-act race.
Money Math
mediumFix floating-point and rounding bugs in the billing service.
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