CRITICAL: Use for domain modeling. Triggers: domain model, DDD, domain-driven design, entity, value object, aggregate, repository pattern, business rules, validation, invariant, 领域模型, 领域驱动设计, 业务规则
Use when designing resource lifecycles. Keywords: RAII, Drop, resource lifecycle, connection pool, lazy initialization, connection pool design, resource cleanup patterns, cleanup, scope, OnceCell, Lazy, once_cell, OnceLock, transaction, session management, when is Drop called, cleanup on error, guard pattern, scope guard, 资源生命周期, 连接池, 惰性初始化, 资源清理, RAII 模式
Use when designing domain error handling. Keywords: domain error, error categorization, recovery strategy, retry, fallback, domain error hierarchy, user-facing vs internal errors, error code design, circuit breaker, graceful degradation, resilience, error context, backoff, retry with backoff, error recovery, transient vs permanent error, 领域错误, 错误分类, 恢复策略, 重试, 熔断器, 优雅降级
Use when learning Rust concepts. Keywords: mental model, how to think about ownership, understanding borrow checker, visualizing memory layout, analogy, misconception, explaining ownership, why does Rust, help me understand, confused about, learning Rust, explain like I'm, ELI5, intuition for, coming from Java, coming from Python, 心智模型, 如何理解所有权, 学习 Rust, Rust 入门, 为什么 Rust
Pattern for wrapping third-party SDK clients (Stripe, Resend, AWS, etc.) with Effect. Use when creating Effect services that wrap external libraries with Promise-based APIs. Provides type-safe error handling, automatic tracing, and clean dependency injection via the "use" pattern.
Design, implement, and review software using vertical slices (feature-first architecture) instead of horizontal layers. Use when creating a new feature, refactoring layered code (controllers/services/repositories), defining clear API-domain-data boundaries, improving slice-level testability, or reducing cross-module coupling in backend or fullstack TypeScript projects.
CloudBase Run backend development rules (Function mode/Container mode). Use this skill when deploying backend services that require long connections, multi-language support, custom environments, or AI agent development.
Spec and no-spec planning workflows derived from local slash commands (requirements, design, tasks).
Dependency Injection pattern for service definitions, factories, and composition roots. Use when working with packages that use the DI pattern.
Event-sourced application state pattern for TypeScript apps. Prefer bounded event logs plus pure derivation functions over mirrored mutable lifecycle flags. Use when state transitions are driven by events and bugs can be reproduced from a saved event stream.
Centralized state management pattern using Zustand vanilla stores. One immutable state atom, functional transitions via setState(), and a single subscribe() for all reactive side effects. Based on Rich Hickey's "Simple Made Easy" principles: prefer values over mutable state, derive instead of cache, centralize transitions, and push side effects to the edges. Resource co-location in the same store is also valid when lifecycle management is safer that way. Also covers state encapsulation: keeping state local to its owner (closures, plugins, factory functions) so it doesn't leak across the app, reducing the blast radius of mutations. Also covers event sourcing: keeping a bounded event buffer and deriving state with pure functions instead of mutable flags, making event handlers easy to test and reason about. Use this skill when building any stateful TypeScript application (servers, extensions, CLIs, relays) to keep state simple, testable, and easy to reason about. ALWAYS read this skill when a project uses zustan
Use when establishing concentric administrative zones or assigning graduated obligations by distance from a capital. Structures five zones (五服) from 甸服 to 荒服, each with specific tribute and governance requirements.
Use when managing tribute obligations or enforcing compliance across distance-based zones. Structures five concentric zones (五服制度) from daily offerings to lifetime homage, with escalation protocols for non-compliance.
Use when besieging a fortified city resistant to conventional assault. Plans river diversion to compromise walls through hydraulic pressure. Based on Wang Ben's 225 BCE flooding of Daliang that forced Wei's surrender.
Use when replacing feudal states with centralized commandery-county (郡县) administration. Establishes 36 commanderies with three-tier governance (守/尉/监), merit-based appointments, and centralized treasury stipends per Li Si's rationale.
Use when commanding troops in a decisive battle requiring total commitment. Applies the 破釜沉舟 (break cauldrons, sink boats) technique to eliminate retreat, limit provisions to 3 days, and force maximum engagement. Based on Xiang Yu at Julu (钜鹿之战).
Use when planning irrigation canals, flood control, or water resource management for agriculture. Applies Yu's principle of channeling over blocking (疏导优于堵塞) and includes the Zheng Guo Canal case study.
Use when designing a multi-step succession sequence to transfer leadership to a designated heir. Models King Shoumeng of Wu's brother-to-brother chain (寿梦→诸樊→余祭→余眜→季札) with safeguards for refusal.
Use when designing governance systems that ensure fair access to justice across all social levels. Covers territorial tours, open-air administration, and prompt dispute resolution following the model of rulers who personally judged cases under trees.
Use when organizing or restructuring military forces into a command hierarchy. Covers the three-army system (三军) with Central, Upper, and Lower armies, staff positions (御戎, 右), communication protocols, and scaling decisions for two-army or three-column (三行) configurations.
Use when facing a numerically superior enemy or planning ambush warfare. Employs Sun Bin's staged retreat (reducing cooking fires from 100,000 to 30,000) to feign mass desertion, plus asymmetric resource allocation (sacrifice weak vs. strong, deploy strong vs. middle) for 2-1 victories.
Use when implementing comprehensive state reforms or transforming governance systems. Follows Shang Yang's model — mutual responsibility (什伍), family structure reform, merit-based ranks replacing hereditary privilege, and standardized weights, measures, and legal codes.
Use when responding to territorial demands from a powerful adversary or deciding how to deploy contested resources. Redirects resources that would be conceded to the aggressor toward the aggressor's enemies instead, building counter-alliances that deter future demands and strengthen negotiating position.
Use when planning systematic territorial expansion across multiple neighboring states. Applies the 远交近攻 doctrine: befriend distant powers, isolate nearby targets, and conquer incrementally for secure, contiguous gains.
