Guides, tips and explanations
A plain Q&A walkthrough of all six JavaScript regex flags — g, i, m, s, u, and y — with before-and-after code examples that show exactly what changes when you toggle each one.
Read more →Most developers read JWTs through a web debugger. This article strips that away entirely — decoding each segment manually in a terminal to show exactly what lives inside the heade…
Read more →Classic crontab still runs on millions of servers, but teams that have outgrown a single Unix box face a hard choice: systemd timers, a heavyweight scheduler like Quartz, or a ful…
Read more →A post-mortem on a real ReDoS incident where a nested quantifier in a JWT subject validator caused catastrophic backtracking, pegging all auth pods at 100% CPU for six minutes. He…
Read more →A forensic walkthrough of every field in an HTTP request and response — methods, headers, status codes, JWT auth, caching, and exactly what each piece controls when you're debuggi…
Read more →A practical email regex pattern for catching obvious garbage, plus an honest argument that overly strict validation rejects real users — and why a confirmation email is the only v…
Read more →JWT tokens and session cookies solve the same problem with fundamentally different tradeoffs. This comparison breaks down scalability, revocation, and security honestly — so you c…
Read more →A scheduled email digest started waking users up at 2:30 AM — and the cron expression looked perfectly correct. Here's the debugging story, the UTC timezone trap that caused it, a…
Read more →Six persistent myths about regular expressions — from "you can't use regex on HTML" to "regex is always slow" — examined and debunked with practical context. Learn where the fears…
Read more →JWTs are everywhere — and so are the same seven implementation mistakes that keep showing up in production APIs. From the alg:none attack to missing revocation logic, here's what …
Read more →Cron expressions look cryptic until you decode each of the five fields. This beginner-friendly guide walks through minute, hour, day-of-month, month, and day-of-week with real exa…
Read more →Zero-width assertions in regex — lookaheads and lookbehinds — solve real validation problems elegantly, but misusing them creates subtle bugs. This step-by-step tutorial uses conc…
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