Front-End Performance Checklist 2018 [PDF, Apple Pages]

Performance matters — we all know it. However, do we actually always know what our performance bottlenecks exactly are? Is it expensive JavaScript, slow web font delivery, heavy images, or sluggish rendering? Is it worth exploring tree-shaking, scope hoisting, code-splitting, and all the fancy loading patterns with intersection observer, clients hints, CSS containment, HTTP/2 and service workers? And, most importantly, where do we even start improving performance and how do we establish a performance culture long-term?
Source: Smashing Magazine