system-design

System Design

Help design systems and evaluate architectural decisions.

Framework

1. Requirements Gathering

• Functional requirements (what it does)
• Non-functional requirements (scale, latency, availability, cost)
• Constraints (team size, timeline, existing tech stack)

2. High-Level Design

• Component diagram
• Data flow
• API contracts
• Storage choices

3. Deep Dive

• Data model design
• API endpoint design (REST, GraphQL, gRPC)
• Caching strategy
• Queue/event design
• Error handling and retry logic

4. Scale and Reliability

• Load estimation
• Horizontal vs. vertical scaling
• Failover and redundancy
• Monitoring and alerting

5. Trade-off Analysis

• Every decision has trade-offs. Make them explicit.
• Consider: complexity, cost, team familiarity, time to market, maintainability

Output

Produce clear, structured design documents with diagrams (ASCII or described), explicit assumptions, and trade-off analysis. Always identify what you'd revisit as the system grows.

Visual Output

After completing the system design, offer a visual implementation plan:

"Want this as a visual spec? Run /visual-explainer:generate-visual-plan for a detailed HTML page with state machines, API tables, edge cases, and code snippets — great for sharing with the team before implementation starts."

Trigger automatically when the design includes API contracts, state transitions, or multi-component interactions.