What's wrong with this Python lambda capturing the wrong value?
What's wrong with this Python lambda capturing the wrong value in a callback. The Python lambda captures the loop variable by reference, so all callbacks see the final value. In Python async this fires wrong handlers.
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Why does this Python os.environ persist across tests?
Why does this Python os.environ persist across tests in pytest. The Python code modifies os.environ in a test without cleanup. In Python test suites this leaks config to other tests.
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What's wrong with this Python API default that hides real zero?
What's wrong with this Python API default that hides real zero in a quota response. The Python code uses or to provide a fallback, so quota remaining of zero becomes unlimited. In Python APIs this breaks rate limiting and lets users exceed limits.
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What's wrong with this Python request context?
What's wrong with this Python request context in a logging pipeline. The Python function uses a mutable default list, so requests share the same trace buffer. In Python APIs this mixes user data and breaks audits.
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Why is this Python price rounding wrong?
Why is this Python price rounding wrong in billing. The Python code builds Decimal from a float, so binary precision leaks into money math. In Python finance this creates off by cents totals.
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Why does this Python cache mutate itself?
Why does this Python cache mutate itself between requests. The Python code caches a list and returns it directly, so callers mutate shared cached state. In Python services this causes ghost data in responses.
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What's wrong with this Python cache refresh?
What's wrong with this Python cache refresh under load. The Python code lets every request recompute the value when it expires, causing a stampede. In Python services this melts the database.
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What's wrong with this Python database loop?
What's wrong with this Python database loop in an API endpoint. The Python code queries once per item, creating an N plus one pattern. In Python services this kills latency and database load.
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Why does this Python worker drop messages?
Why does this Python worker drop messages in production. The Python code acknowledges the queue before the database commit, so failures lose data permanently. In Python pipelines this creates silent gaps.
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Why is this Python command injection possible?
Why is this Python command injection possible in a media service. The Python code builds a shell command with user input and runs it with shell=True. In Python backends this allows attackers to execute commands.
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What's wrong with this Python asyncio gather?
What's wrong with this Python asyncio gather in a fan-out call. The Python code lets one failure cancel all other tasks, so partial writes never finish. In Python services this causes missing records and inconsistent state.
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What's wrong with this Python account transfer?
What's wrong with this Python account transfer in production. The Python code updates two balances without a transaction, so crashes leave money missing or duplicated. In Python finance services this creates inconsistent ledgers.
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Why is this Python cache a security risk?
Why is this Python cache a security risk in production. The Python code unpickles data from a client controlled source, which can execute arbitrary code. In Python services this is a remote code execution vulnerability.
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Why does this Python cache serve the wrong language?
Why does this Python cache serve the wrong language in production. The Python code caches responses without locale in the key, so users see another language. In Python APIs this becomes a localization incident.
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