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Why Your JWT Breaks in URLs: The Base64URL Mistake 9 in 10 Engineers Ship

By xiezixing 2026年7月23日

Base64URL is not Base64 — and the difference breaks a JWT every time it travels through a URL. Here is the alphabet, the two-line fix, and the three workflows that catch the wrong encoding.

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The OpenAPI Diff Your CI Does Not Run: Why Two Specs Can Look Compatible and Still Break Every Client

By xiezixing 2026年6月16日

The breaking change you ship to production is almost never the one a human reviews.…

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Why Every Tracking Number You Copy-Paste Is Probably a String, Not a Number

By xiezixing 2026年6月15日

Why Every Tracking Number You Copy-Paste From an Email Is Probably a String, Not a…

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The 30-Second Check That Catches API Changes Before They Break Production

By xiezixing 2026年6月6日

A junior engineer added a required field to a POST /v1/orders endpoint last Tuesday. The…

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8 Free Developer Tools That Replace Hours of Boilerplate Work

By xiezixing 2026年4月12日

8 Free Developer Tools That Replace Hours of Boilerplate Work Every developer knows the feeling.…

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8 Free JSON Tools That Close the Gap Between Your API Design and Your Code

By xiezixing 2026年4月6日

8 Free JSON Tools That Close the Gap Between Your API Design and Your CodeMost…

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8 Free Validation Tools That Catch the Data Errors Your Forms Let Slip Through

By xiezixing 2026年3月31日

8 Free Validation Tools That Catch the Data Errors Your Forms Let Slip Through A…