VersoXBT

Test organization, fixtures, factories (factory_boy/faker), test isolation, database cleanup, and test configuration. Use when the user is setting up a test suite, organizing test files, creating test fixtures, or dealing with test isolation issues.

Guide for writing Docker Compose files with services, networks, volumes, health checks, and environment management. Use when the user creates or modifies docker-compose.yml, asks about multi-container setups, local development environments, or service orchestration. Trigger whenever Docker Compose, multi-container, or local dev environment is mentioned.

Patterns for running independent tasks in parallel using multiple tool calls and Agent invocations. Use when the user has multiple independent operations, asks about fan-out/fan-in, or wants to speed up multi-step workflows.

Enforce strict TypeScript compiler settings and type narrowing patterns. Use when the user creates a new TypeScript project, configures tsconfig.json, encounters null/undefined errors, deals with indexed access issues, or asks about strict mode, type safety, or narrowing techniques.

Advanced TypeScript type patterns for modeling complex domains safely. Use when the user needs discriminated unions, branded types, template literal types, type guards, exhaustive checking, const assertions, or is designing type-safe APIs and domain models.

Enforce pull request best practices: size limits, description templates, testing requirements, and review workflows. Activate whenever the user creates a PR, asks about PR best practices, sets up PR templates, discusses code review turnaround, or mentions PR size, review requirements, or branch protection rules.

Patterns for auto-format on save, auto-lint, auto-test on file change, and CI triggers within Claude Code. Use when the user wants automated reactions to file changes, wants to set up continuous feedback loops, or asks about triggering actions automatically.

React component composition patterns including compound components, render props, HOCs, and controlled vs uncontrolled components. Use when the user is building React components, asking about component architecture, refactoring components, or designing reusable UI APIs. Trigger on mentions of compound components, render props, higher-order components, forwardRef, composition, or component design p

Enforce consistent naming conventions for variables, functions, files, and more. Use when the user names variables, functions, classes, files, database columns, or constants. Apply when reviewing code for naming consistency or when the user asks about naming best practices.

Read stack traces, follow error chains, and trace errors to their root cause. Use when the user encounters an error message, stack trace, exception, or crash. Apply when debugging async errors, React error boundaries, source map issues, or when an error message is unclear.

Strategies for managing AI agent context windows including optimization, summarization, retrieval-augmented generation, progressive disclosure, and pruning. Use when the user is hitting context limits, building long-running agents, implementing RAG, optimizing token usage, or designing systems that need to manage large amounts of information within limited context windows.

Mocks vs stubs vs spies, dependency injection for testing, jest.mock/unittest.mock/gomock, and when NOT to mock. Use when the user needs to isolate dependencies in tests, asks about mocking external services, or has tests tightly coupled to implementation details.