Joan León Hi!
RSS FeedWelcome to this space where I share learnings about different topics related to the Front-end world, especially Web Performance.
Recent Posts
A 301 on every click: the trailing slash that slowed down all internal navigation
Published:A real finding on skills.addy.ie: every internal link triggered a 301 redirect on Netlify because of a missing trailing slash. What it costs the UX, how I spotted it in DevTools, the quick fix I first thought of, and the underlying solution (Astro directory format + trailingSlash: 'always'). With Network panel evidence before and after.
Keep-Alive is not Cache-Control: anatomy of a network waterfall
Published:A real audit case: two heavy images (608 KB and 403 KB) over HTTP/1.1 with Connection: Keep-Alive but no Cache-Control. Why they are different things, what HTTP/2 fixes and how preconnect gets ahead of the handshake. With an interactive waterfall demo.
The mystery of the self-repainting #document: Paint flashing and composited layers
Published:Why the #document layer racks up hundreds of repaints at rest because of a ticker animated with transform, how to catch it with the Layers tab and Paint flashing, and how to promote the element to its own composited layer with will-change.
Antigravity Skills: advanced YAML frontmatter configuration
Published:The kind, model, temperature, max_turns and tools fields in SKILL.md frontmatter let you precisely control how each agent runs in Antigravity. A practical guide to the extended fields that Google hasn't officially documented yet.