name: projection-patterns
description: Build read models and projections from event streams. Use when implementing CQRS read sides, building materialized views, or optimizing query performance in event-sourced systems.

Projection Patterns

Comprehensive guide to building projections and read models for event-sourced systems.

Use this skill when

• Building CQRS read models
• Creating materialized views from events
• Optimizing query performance
• Implementing real-time dashboards
• Building search indexes from events
• Aggregating data across streams

Do not use this skill when

• The task is unrelated to projection patterns
• You need a different domain or tool outside this scope

Instructions

• Clarify goals, constraints, and required inputs.
• Apply relevant best practices and validate outcomes.
• Provide actionable steps and verification.
• If detailed examples are required, open resources/implementation-playbook.md.

Resources

• resources/implementation-playbook.md for detailed patterns and examples.