Developer Guides
Follow practical developer guides that explain context and boundaries and lead to relevant tools.
Unix timestamps: seconds vs. milliseconds
Why 1700000000 is a date and 1700000000000 is also a date, which unit your system uses, and how to avoid the classic off-by-1000 bug.
CIDR notation and subnet math
What /24 really means, how to read a CIDR block's size at a glance, and the handful of blocks every developer should recognize.
Base64, Base64URL, and Data URIs
What Base64 encoding is for, why it makes data 33% bigger, how the URL-safe variant differs, and where Data URIs fit in.
JWT anatomy: decode vs. verify
The three segments of a JSON Web Token, what decoding tells you and what it does not, and the claims that matter when debugging auth.
HTTP errors: a debugging field guide
How to triage 4xx vs 5xx, what 502/503/504 each tell you about your stack, and the client errors that waste the most time.
Cron expressions, explained field by field
The five fields of a cron schedule, the operators that shape them, timezone pitfalls, and the differences between Unix cron and its modern variants.
Standards behind the guides
Protocol and format facts link back to the relevant standards or maintained documentation, so you can verify the original definition when needed.