technical-decision-record

期待される結果:

• # ADR-001: Use PostgreSQL for User Profile Service
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• **Status**: Accepted
• **Date**: 2024-01-21
• **Deciders**: Engineering Team
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• ## Context
• We need to select a database for storing user profile data in our new microservice. The service will handle user accounts, preferences, and authentication tokens.
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• ## Constraints
• - Must integrate with existing Node.js backend
• - Need ACID compliance for transaction safety
• - Team has PostgreSQL experience, limited MongoDB experience
• - Budget does not support managed database services
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• ## Options Considered
• ### Option 1: PostgreSQL
• - Pros: ACID compliance, strong relationships, team familiarity
• - Cons: Requires schema migration, less flexible for unstructured data
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• ### Option 2: MongoDB
• - Pros: Schema flexibility, easy horizontal scaling
• - Cons: No ACID transactions, learning curve for team
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• ## Decision
• We will use PostgreSQL.
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• ## Consequences
• - Positive: Reliable transactions, clear data model
• - Negative: Schema changes require migrations
• - Risks: Performance at extreme scale
• - Reversibility: Moderate - data migration required

期待される結果:

• # ADR-042: Adopt gRPC for Internal Service Communication
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• **Status**: Accepted
• **Date**: 2024-01-21
• **Deciders**: Platform Team
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• ## Context
• Our microservices currently use REST over HTTP for inter-service communication. Performance bottlenecks and payload size are becoming issues as we scale.
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• ## Constraints
• - Must support TypeScript and Go services
• - Need backward compatibility with existing REST APIs during transition
• - Network efficiency is critical for high-volume services
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• ## Decision
• We will adopt gRPC for new internal services with protobuf contracts.
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• ## Consequences
• - Positive: Smaller payloads, faster serialization, type safety
• - Negative: Requires learning curve, browser clients cannot use gRPC directly
• - Risks: Debugging complexity increases
• - Reversibility: Difficult - contracts become tightly coupled