Specifications in Go: Composable Query Predicates Without an ORM Leak
The article discusses the Specification pattern in Go as a solution to increasingly complex and unwieldy repository query methods that evolve over time. By representing query predicates as composable domain objects, the pattern allows for clean, readable, and testable code without relying on an ORM. The repository interface simplifies to a single method, FindAll(spec), while specifications can be combined using logical operators like AND, OR, and NOT.
- ▪The Specification pattern was introduced by Eric Evans and Martin Fowler and popularized in Domain-Driven Design.
- ▪Specifications are first-class domain objects that implement an IsSatisfiedBy method for in-memory testing and filtering.
- ▪Go generics (1.18+) enable clean, type-safe composition of specifications using And, Or, and Not combinators.
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try { if(localStorage) { let currentUser = localStorage.getItem('current_user'); if (currentUser) { currentUser = JSON.parse(currentUser); if (currentUser.id === 425693) { document.getElementById('article-show-container').classList.add('current-user-is-article-author'); } } } } catch (e) { console.error(e); } Gabriel Anhaia Posted on May 1 Specifications in Go: Composable Query Predicates Without an ORM Leak #go #architecture #ddd #backend Book: Hexagonal Architecture in Go Also by me: Thinking in Go (2-book series) — Complete Guide to Go Programming + Hexagonal Architecture in Go My project: Hermes IDE | GitHub — an IDE for developers who ship with Claude Code and other AI coding tools Me: xgabriel.com | GitHub You've seen this repository file.
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