A multi-device viewer, a pattern quiz, and a reference library.
Viewer
Preview any URL on phones, tablets, and desktops with synced scroll, click, and navigation.
Play
Pick the better responsive pattern in 10 side-by-side code challenges. Daily and weekly seeds included.
Learn
128 patterns across 16 categories. Each shows the fragile approach, the resilient one, and why it matters.
Can't Maintain
React component API design. Props, composition, and patterns.Can't Type
TypeScript patterns. Generics, narrowing, utility types, and common mistakes.Can't Orchestrate
Container orchestration patterns. Docker, Kubernetes, CI/CD, and Helm.Can't SEO
SEO best practices for Next.js. Meta tags, Open Graph, structured data, and more.Can't UX
UX design patterns. Typography, spacing, color, hierarchy, layout, and forms.Can't Explode
Chemistry challenges. Molecular stability, acid strength, bond energy, and electronegativity.