Tutorials, deep-dives, and privacy-first thinking about developer tools.
Showing 13–24 of 35 posts
Ignore whitespace in a diff and you cut formatting noise — but the same flag can hide real bugs in Python, YAML, and Makefiles. Here's when to use it.
Side-by-side and unified diff show the same edits two ways. Learn how each format reads, what the @@ hunk header means, and when to pick which.
Understand regex capture groups, backreferences, and the $1, $&, and $<name> replacement tokens — with copy-paste JavaScript examples that actually work.
Regex lookahead vs lookbehind, explained with five production patterns: password rules, thousands separators, price parsing, and camelCase splits.
A pattern that works in PCRE can silently break in JavaScript or Python re. Here are the regex flavor differences that explain why, with fixes for each.
EXIF stripping happens automatically when you re-encode an image — convert or compress a photo and its GPS coordinates and camera data vanish. Here's why.
Converted a PNG to JPG and the file grew? Here's why JPEG bloats flat graphics and screenshots, and the quick fix that actually shrinks the image.
Unix timestamp 1700000000 was Tuesday, November 14, 2023, 22:13:20 UTC. Learn how to date any timestamp from its leading digits, no converter needed.
JWT exp, nbf, and iat are Unix timestamps in seconds. Learn to read them in 3 seconds, convert them to a date, and check token expiry by hand.
The Year 2038 problem overflows 32-bit Unix time on 19 Jan 2038. Here's who is still affected in 2026 and how to test your own systems for it.
Learn what the JWT exp, nbf, and iat claims mean, how to read token expiry without doing epoch math by hand, and the clock-skew gotchas that bite in 2026.
Your JavaScript timestamp is in milliseconds while most backends use seconds, so it looks 1000× too big. Here is why, and how to convert it safely.