Tutorials, deep-dives, and privacy-first thinking about developer tools.
Showing 25–36 of 105 posts
A UUID regex that only checks the 8-4-4-4-12 shape accepts garbage. Here's how to validate the version and variant nibbles the way RFC 9562 defines them.
Five regex mistakes that make a pattern match too much — greedy .*, unescaped dots, missing anchors, loose alternation, nested quantifiers — with the fix for each.
Line-level diff shines for code review; word-level diff catches the one edited word inside a long paragraph. Here's when to reach for each in 2026.
The LCS algorithm is how a diff tool finds the fewest insertions and deletions between two texts. Here is how longest common subsequence actually works.
A practical guide to regex find and replace in VS Code: capture groups, $1 substitution, case modifiers, and the side-by-side diff preview.
Learn regex for log parsing: copy-ready patterns to extract timestamps, IPv4 addresses, and HTTP status codes from access logs, with named capture groups.
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.
How to validate phone numbers with regex across country formats: the E.164 pattern that always works, US patterns, and where regex stops working.
Understand regex capture groups, backreferences, and the $1, $&, and $<name> replacement tokens — with copy-paste JavaScript examples that actually work.
A diff checker compares any two texts in seconds, right in your browser — no upload, no sign-up. Learn how diff algorithms work and when to use one.
A browser image converter often beats Photoshop's Save As for plain format changes, batch jobs, and privacy. Here is exactly when each one wins in 2026.