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Security & Reliability

Defensive engineering for .NET APIs, including injection, denial of service, retries, rate limits, and failure-safe design.

8 min read

Path Traversal Vulnerability in ASP.NET Core

A path traversal vulnerability lets user input escape a trusted directory. See the unsafe C# patterns, the containment check, and tests that prove it.

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8 min read

Idempotency in API design: surviving the retry you didn't send

Every serious client retries. How the idempotency key pattern and a database unique constraint keep a retried payment from becoming two charges.

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8 min read

Rate limiting algorithms: how token buckets forgive bursts

Rate limiting algorithms compared: why fixed windows leak double the limit, how token buckets forgive bursts, and what a good 429 response returns.

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7 min read

ReDoS: the innocent regex that can take down your API

Catastrophic backtracking turns an email regex into a denial of service: 30 characters, nearly a minute of CPU. Why nested quantifiers explode and how .NET lets you defuse them.

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8 min read

The OWASP Top 10 through a C# lens

A practical tour of the OWASP Top 10 for .NET developers: the ASP.NET Core and EF Core patterns behind broken access control, injection, SSRF, and overposting.

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6 min read

SQL injection is still alive, and it's hiding in your C#

SQL injection is supposedly solved, yet it's still in the OWASP Top 10. The C# patterns that keep it alive in EF Core and ADO.NET, and how to kill them.

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