the skills that actually get you hired (not 500 leetcodes):
• auth flows (oauth, jwt, sessions)
• db schema design & migrations
• caching (redis, cdn)
• background jobs & queues
• file uploads & storage
• realtime (websockets, pub/sub)
• forms & validation
• state management
• testing (unit e2e)
• deploys & monitoring
leetcode won’t save you. this stack will.