Optimistic Offline Lock Implementer

Use when offline-concurrency-strategy-selector (or your team) has chosen Optimistic Offline Lock and you need to implement it correctly end-to-end. Handles: adding a version column (integer, not timestamp), version-conditioned UPDATE and DELETE SQL (WHERE id=? AND version=?), row-count-zero collision detection, ConcurrencyException with modifiedBy+modified context, stale-version prevention, version round-tripping from server to client and back, Unit of Work commit integration (checkConsistentReads → insertNew → deleteRemoved → updateDirty with rollback on exception), ORM-native version support (@Version annotation JPA/Hibernate, [ConcurrencyCheck] or [Timestamp] EF Core, version_id_col SQLAlchemy, lock_version Rails, django-concurrency), and collision UX design (merge / force-save / abandon — not just a 409 error). Also handles: optimistic locking, optimistic offline lock, concurrent edit collision detection, lost update prevention, conditional update, concurrency version check, OptimisticLockException, DbUpdateConcurrencyException, StaleObjectError, inconsistent read protection, checkCurrent early-failure, anti-pattern audit (missing WHERE clause, non-incremented version, stale in-memory object retry, timestamp versioning). Produces an implementation plan covering schema, ORM config, version round-trip path, collision UX spec, test plan, and anti-pattern checklist.

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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

› /optimistic-offline-lock-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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