Validates compilation of generated Fakt fakes and diagnoses build failures. Covers type safety, smart defaults, DSL typing, error classification, and root cause analysis. Use when compilation fails, generated code has errors, validating type safety, verifying changes compile before committing, or checking if generated code is valid. Make sure to use this skill whenever a build error mentions generated fakes or the Fakt plugin — even if the root cause might be elsewhere, this skill's error classification pinpoints the actual source.
Queries Kotlin compiler source code for API validation, compatibility checks, and breaking change detection. Use when validating Kotlin compiler APIs, checking IrGenerationExtension compatibility, analyzing compiler plugin API usage, or verifying that an API hasn't been deprecated or removed in a newer Kotlin version. Make sure to use this skill whenever compiler plugin code references Kotlin internal APIs — these APIs change frequently between Kotlin versions and silent breakage is common.
Runs BDD-compliant GIVEN-WHEN-THEN tests, validates naming compliance, and analyzes coverage. Use when running tests, checking BDD compliance, validating test patterns, or verifying that test names follow GIVEN-WHEN-THEN conventions. Make sure to use this skill whenever tests need to be executed — it validates naming compliance and catches convention violations that plain test runners miss.
Analyzes code behavior and generates comprehensive GIVEN-WHEN-THEN unit tests with vanilla JUnit5. Use when generating tests, analyzing behavior for test coverage, creating unit tests for Fakt components, or writing tests for new or modified code. Make sure to use this skill whenever new tests need to be written — it ensures BDD naming compliance, proper test isolation, and coverage of edge cases that are easy to overlook.
Documents the Fakt code generation pipeline — immutable AST model, builder DSL, renderer, default value strategies, and extension functions. Use when modifying code generation, changing generated output, adding new generated patterns, understanding builders or renderers, adding a new default value strategy, or debugging generated output. Make sure to use this skill whenever generated Kotlin code needs to change — the pipeline has strict conventions (immutable AST, builder DSL, renderer separation) that must be followed even for small changes.
Validates Fakt follows compiler plugin best practices — two-phase FIR→IR, context-driven generation, CompilerPluginRegistrar structure. Use when validating architecture, checking plugin structure, reviewing compiler patterns, or verifying that FIR and IR phases remain properly separated. Make sure to use this skill whenever compiler plugin code is modified — phase mixing and registration issues are subtle bugs that only surface at runtime.
Navigates Fakt documentation — both internal contributor docs (.claude/docs/) and public MkDocs site (docs/). Use when looking for docs about architecture, testing, code generation, setup, troubleshooting, or any project convention. Make sure to use this skill whenever you need to find documentation — it knows the full doc tree structure and avoids wasting time searching in the wrong locations.
Guides step-by-step through all 11 touchpoints for adding a new @Fake annotation option (like mutability or callHistory). Covers annotation enum, CLI processor, Gradle plugin, FIR metadata, IR bridge, analysis models, and code generators. Use when adding a new option to @Fake, adding a new enum to the annotation, making something configurable per-interface, implementing a new compiler plugin feature flag, adding a new Gradle extension property, or extending the three-tier resolution (annotation → plugin → default). Make sure to use this skill whenever a change touches more than one layer of the option pipeline, even for small additions like a new enum value.