--- name: mongodb description: MongoDB schema design, aggregation pipelines, indexing strategies, and performance. allowed-tools: Read, Write, Edit, Bash, Glob, Grep --- # MongoDB Skill Expert assistance for MongoDB database design and operations. ## Capabilities - Design document schemas - Build aggregation pipelines - Create optimal indexes - Implement data modeling patterns - Configure replication and sharding ## Aggregation Pipeline ```typescript const results = await collection.aggregate([ { $match: { status: 'active' } }, { $group: { _id: '$category', total: { $sum: '$amount' } } }, { $sort: { total: -1 } }, { $limit: 10 }, ]).toArray(); ``` ## Indexing ```typescript // Compound index await collection.createIndex({ userId: 1, createdAt: -1 }); // Text index await collection.createIndex({ title: 'text', content: 'text' }); ``` ## Target Processes - mern-stack-development - database-design - backend-development