Lazy Load Strategy Implementer

Implement Lazy Load (deferred loading) correctly in a persistence layer to avoid N+1 queries, ripple loading, and proxy identity traps. Use when encountering slow object graph loads, N+1 query problems, out-of-memory on eager loading, ORM lazy loading misconfiguration, or deciding between eager vs lazy loading strategies. Applies to: Hibernate FetchType.LAZY / @BatchSize, SQLAlchemy lazy='select'/'selectin'/'subquery', Django select_related / prefetch_related, EF Core Include() vs Load(), TypeORM eager/lazy relations, Rails includes/preload/eager_load, hand-rolled Data Mapper with virtual proxy patterns. Covers all four implementation variants — lazy initialization, virtual proxy, value holder, ghost — with applicability rules and trade-off analysis. Identifies and fixes the ripple loading anti-pattern (N+1 on collections), the proxy identity trap (two proxies, same row, broken equality), and misuse of Lazy Load on small graphs that should just be eagerly loaded. Produces an implementation plan: chosen variant, ORM configuration or code sketch, batch loading config, eager-load overrides for hot paths, Identity Map integration, and a ripple-loading audit. Requires knowing the data-source pattern already in use (Data Mapper / ORM vs Active Record); if unknown invoke data-source-pattern-selector first.

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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

› /lazy-load-strategy-implementer

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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