This one walks you through production GraphQL APIs with Apollo Server 4, from schema design to subscriptions. It covers the stuff that actually matters: DataLoader patterns to avoid N+1 queries, proper resolver chains, cursor-based pagination, and real-time subscriptions over WebSocket. The examples show complete server setups with authentication context, input validation, and error handling. If you're building a GraphQL API and need to handle schema federation, query complexity limits, or just want to understand why your resolvers are slow, this has the patterns. Particularly solid on the DataLoader batching implementation, which is usually where teams mess up performance.
npx skills add https://github.com/personamanagmentlayer/pcl --skill graphql-expert