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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.

498 guides published 17 topic areas Latest guide Oct 2026

Tagged Security · 10 guides

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A laptop screen showing two panes of source code side by side

Developer Tools 4 min

How to Self-Host Gitea or Forgejo with Docker

The environment variable that closes public registration was renamed, so copying an older tutorial leaves your git host...

Kenji Tanaka

Pub. 31 Aug

Ethernet cables plugged into a network switch with green status lights

Developer Tools 4 min

How to Set Up Caddy as a Reverse Proxy with Docker

Caddy gets certificates without being asked, which is why it is the right first reverse proxy. The confusion starts with...

Kenji Tanaka

Pub. 31 Aug

Two padlocks, one blue and one brass, hanging from a chain against a brick wall.

Developer Tools 5 min

How to Self-Host Vaultwarden with Docker

The compose file is trivial. The admin token is not: it wants an Argon2 hash rather than a password, and the hash then b...

Kenji Tanaka

Pub. 31 Aug

A row of metro fare gates, some displaying a green tick and others a red cross, beneath station departure signage

Developer Tools 6 min

What Your Rate Limit Actually Limits

A route limited to 30 a minute and one limited to 60 turned out to share a single counter, because the framework keys it...

Kenji Tanaka

Pub. 22 Aug

A wooden hand plane resting on a fresh length of planed timber against a weathered plank wall, its blade and wedge still seated and its handle worn smooth from use.

Developer Tools 6 min

How Old Is the Code You Installed?

The median package in this site's tree was published 286 days ago — but one in five has seen no release in two years, an...

Kenji Tanaka

Pub. 20 Aug

An antique wooden telephone switchboard, its rows of brass jack sockets and cloth-covered cables still wired into place, with two handset earpieces resting on the bench in front of it.

Developer Tools 6 min

Your Bank Is Still on IPv4

We asked DNS whether 18 institutions across six ASEAN economies — the largest bank, the government portal and the bigges...

Maya Lin

Pub. 19 Aug

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