This skill should be used when the user asks to "define a feature", "create a BaseFeature class", "track feature versions", "set up metadata store", "field-level lineage", "FieldSpec", "FeatureDep", "run metaxy CLI", "metaxy migrations", "metaxy lock", "lock features", "external features", "multi-environment", "monorepo features", "enable Map datatype", "enable_map_datatype", or needs guidance on metaxy feature definitions, versioning, metadata stores, CLI commands, testing patterns, feature locking, Map datatype configuration, or multi-environment configuration.
This skill should be used when the user asks to "add a tach module", "configure tach layers", "define module boundaries", "set up interfaces", "run tach check", "check module boundaries", "tach sync", "tach show", "deprecate a dependency", "tach-ignore", "unchecked modules", "tach test", "skip tests with tach", "configure tach.toml", "source roots", "forbid circular dependencies", "enforce module boundaries", "set up architectural layers", or "tach init".
Use Sybil for testing code examples in documentation and docstrings. Covers pytest integration, parsers, skip directives, and namespace management.
Effectively use Narwhals to write dataframe-agnostic code that works seamlessly across multiple Python dataframe libraries. Write correct type annotations for code using Narwhals.
Use syrupy for pytest snapshot testing to ensure the immutability of computed results, manage snapshots, customize serialization, and handle complex data structures with built-in matchers and filters.
Write YAML front matter for documentation pages with appropriate titles and descriptions for social cards.
Self-reflect on the current session to identify mistakes and propose improvements to .claude configuration (CLAUDE.md, hooks, skills).
Use Hypothesis for property-based testing to automatically generate comprehensive test cases, find edge cases, and write more robust tests with minimal example shrinking. Includes Polars parametric testing integration.