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Developer Tools guides

Step-by-step how-tos, head-to-head comparisons and honest roundups — every guide worked through with current figures, then backed by a RECATOOLS calculator or AI-directory entry so you can act on it.

185 guides published 15 topic areas Latest guide Aug 2026

Tagged Security · 4 guides

All 185 AI & ML 47 Finance 27 Cybersecurity 24 Developer Tools 20 Science 10 Chinese Culture 9

A portable solid-state drive and a small USB stick on a wooden desk beside a keyboard.

Developer Tools 7 min

Can a Deleted File Be Recovered? We Erased the Whole Volume and Read It Back

We wrote a file marked so it could not be mistaken for anything else, deleted it, then erased the entire volume the way...

Kenji Tanaka

Pub. 11 Aug

Three white dice resting on a chessboard under a shaft of light.

Developer Tools 16 min

Why "Random" Is Almost Never Random — and What a Fairness Test Cannot See

We fed the same rejection-sampling helper a cryptographic source and a 1960s textbook generator, 600,000 draws each. The...

Kenji Tanaka

Pub. 2 Aug

Developer Tools 17 min

Decoding a JWT Is Not Verifying It

A decoder shows you the claims; it does not tell you whether to believe them. RFC 7519 §7.2 lists ten validation steps a...

Kenji Tanaka

Pub. 25 Jul

Developer Tools 16 min

Encoding Is Not Encryption: Base64, Percent-Encoding and the Confusion That Leaks Data

The RFC that defines Base64 says in its own Security Considerations that base encoding "visually hides" a password but "...

Kenji Tanaka

Pub. 25 Jul