Enterprise Base Pattern Catalog

Reference catalog for Fowler's 11 enterprise base patterns from Chapter 18 of PEAA. Use when another skill or user says 'we need a Gateway here', 'this should be a Value Object', 'replace nulls with a Special Case', 'use a Service Stub for testing', or 'separate this interface from its implementation'. Covers all 11 base patterns: Gateway pattern (wrapping external systems), Mapper pattern (decoupling subsystems), Layer Supertype (shared base class per layer), Separated Interface (dependency inversion packaging), Registry (service locator), Value Object (value-identity immutable objects), Money pattern (monetary arithmetic, no floats, allocate-by-ratio), Special Case / Null Object (replace null checks), Plugin pattern (runtime-bound implementation), Service Stub (test double for external services), Record Set (generic tabular data structure). Identifies which pattern fits a described problem, provides canonical definition and modern language parallels, distinguishes Gateway (generic external-access wrapper) from Table Data Gateway (data-access pattern), flags Registry vs DI container tradeoff, and produces a short design note with implementation sketch. Also routes to the appropriate family selector when the problem is not a base pattern.

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Install

Claude CodeClawhHubnpxCursorCodexGemini CLI

1. Add marketplace

› /plugin marketplace add bookforge-ai/bookforge-skills

2. Install plugin

› /plugin install patterns-of-enterprise-application-architecture@bookforge-skills

3. Use the skill

› /enterprise-base-pattern-catalog

CC-BY-SA · Open sourceGitHub

Source Book

Patterns of Enterprise Application Architecture

Martin Fowler, David Rice, Matthew Foemmel, Edward Hieatt, Robert Mee, Randy Stafford

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