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Plain-English guides to the non-obvious parts of common developer-tool topics. Each article maps to one or more JustKit tools.
Articles
5 guidesJWT, Explained
The three parts, the claims that matter, and the security pitfalls almost every team hits.
UUID v4 vs v7 vs Others
Why v7 (Dec 2024) is the right default for new database keys, and when v4 still wins.
CIDR Notation Explained
Prefix length, mask math, RFC 1918 ranges, IPv6 differences, and why /31 is special.
Regex by Example
Anchors, classes, quantifiers, lookarounds — plus 12 patterns you'll actually reach for.
Base64 Encoding Explained
Why it exists, the 33% penalty math, MIME vs JWT vs data URL contexts, URL-safe variant.