Frontend Performance

Optimize frontend applications for maximum Lighthouse scores and real-user performance. This skill covers the technical performance layer -- for how it looks, see sheleg-design; for what the interface must do, see super-ux.

Audit Workflow

1. Measure -- Run PageSpeed Insights or Lighthouse (Chromium) and load the same scenario in WebKit first (see Test browser below). Record scores, failing audits and the engine of each number.
2. Diagnose -- Map each failing audit to a specific code-level cause (see checklist below).
3. Prioritize -- Fix by impact: P0 blocks rendering, P1 hurts metrics, P2 is informational.
4. Implement -- Apply fixes per the reference guides.
5. Validate -- next build (or framework equivalent) + re-run Lighthouse and the WebKit run. Verify no regressions in either engine.

Test browser — WebKit (Safari) first