Tutorials, deep-dives, and privacy-first thinking about developer tools.
Showing 1–5 of 5 posts
How an online stopwatch with lap times works: laps vs splits, why performance.now() beats setInterval, and how accurate browser timing really is.
Why a browser online timer drifts, how throttling in background tabs slows it down, and how to run a countdown that stays accurate to the second.
How the EyeDropper API lets a web app sample any pixel on the screen, the exact JavaScript to call it, and the fallback you still need in 2026.
Understand regex capture groups, backreferences, and the $1, $&, and $<name> replacement tokens — with copy-paste JavaScript examples that actually work.
Sign a JWT in the browser with HS256 and the Web Crypto API — five lines of JavaScript, no library, no server. The 2026 walkthrough.