Software Engineering Skills
Browse 1,059 curated software engineering skills for Claude Code, Cursor, and Codex. License-verified, MCP-ready, free to start.
Jira Epic
Creates Jira epics for large features following Prowler's standard format. Trigger: When user asks to create an epic, large feature, or multi-task initiative.
Jira Task
Creates Jira tasks following Prowler's standard format. Trigger: When user asks to create a Jira task, ticket, or issue.
Joyride User Scripts Project Assistant
Expert assistance for Joyride User Script projects - REPL-driven ClojureScript and user space automation of VS Code
Joyride Workspace Automation Assistant
Expert assistance for Joyride Workspace automation - REPL-driven and user space ClojureScript automation within specific VS Code workspaces
Judge
Reviewing code via multi-engine orchestration. Orchestrates parallel review via subagents with grounding verification, shipping only findings worth fixing. Default Claude + Codex (dual-engine); agy optional third axis. Use for PR review or pre-commit checks — detects bugs, vulnerabilities, logic errors, and intent misalignment. Complements Zen refactoring.
Jules
Delegate coding tasks to Google Jules AI agent for asynchronous execution. Use when user says: 'have Jules fix', 'delegate to Jules', 'send to Jules', 'ask Jules to', 'check Jules sessions', 'pull Jules results', 'jules add tests', 'jules add docs', 'jules review pr'. Handles: bug fixes, documentation, features, tests, refactoring, code reviews. Works with GitHub repos, creates PRs.
Junit 5 Skill
Generates production-grade JUnit 5 unit and integration tests in Java. Covers assertions, parameterized tests, lifecycle hooks, mocking with Mockito, and nested tests. Use when user mentions "JUnit", "JUnit 5", "@Test", "assertEquals", "Assertions", "Java unit test". Triggers on: "JUnit", "@Test", "assertEquals", "Java test", "unit test Java".
Jupiter
Build Solana DeFi applications combining Jupiter APIs with Helius infrastructure. Covers token swaps (Swap API V2), lending/borrowing (Lend protocol), limit orders (Trigger), DCA (Recurring), token/price data, transaction submission via Sender, fee optimization, real-time streaming, and wallet intelligence.
Jupiter
Build Solana DeFi applications combining Jupiter APIs with Helius infrastructure. Covers token swaps (Swap API V2), lending/borrowing (Lend protocol), limit orders (Trigger), DCA (Recurring), token/price data, transaction submission via Sender, fee optimization, real-time streaming, and wallet intelligence.
Justfile
Create, edit, refactor, lint, and maintain Justfiles and `.just` module files using the `just` command runner. ALWAYS use this skill when the user mentions justfile, Justfile, just recipes, just modules, `.just` files, or asks to set up task automation with just. Also trigger when migrating a Makefile to just, adding recipes or modules to an existing Justfile, or organizing and documenting project commands. Covers house conventions, templates, namespacing by domain, dotenv, cross-platform support, and a structural lint. NOT FOR file-based build dependency graphs that need timestamp tracking (use make).
Keyboard Navigator
Keyboard navigation and focus management specialist. Use when building or reviewing any interactive web component, navigation, routing, single-page app transitions, tab order, keyboard shortcuts, focus traps, or skip links. Ensures full keyboard operability for users who cannot use a mouse. Applies to any web framework or vanilla HTML/CSS/JS.
Kotlin Backend Jpa Entity Mapping
Model Kotlin persistence code correctly for Spring Data JPA and Hibernate. Covers entity design, identity and equality, uniqueness constraints, relationships, fetch plans, and common ORM (Object-Relational Mapping) traps specific to Kotlin. Use when creating or reviewing JPA (Java Persistence API) entities, diagnosing N+1 or LazyInitializationException, placing indexes and uniqueness rules, or preventing Kotlin-specific bugs such as data class entities and broken equals/hashCode.
Kotlin MCP Server Development Expert
Expert assistant for building Model Context Protocol (MCP) servers in Kotlin using the official SDK.
Kotlin Specialist
Provides idiomatic Kotlin implementation patterns including coroutine concurrency, Flow stream handling, multiplatform architecture, Compose UI construction, Ktor server setup, and type-safe DSL design. Use when building Kotlin applications requiring coroutines, multiplatform development, or Android with Compose. Invoke for Flow API, KMP projects, Ktor servers, DSL design, sealed classes, suspend function, Android Kotlin, Kotlin Multiplatform.
Kotlin Tooling Agp9 Migration
Migrates Kotlin Multiplatform (KMP) projects to Android Gradle Plugin 9.0+. Handles plugin replacement (com.android.kotlin.multiplatform.library), module splitting, DSL migration, and the new default project structure. Use when upgrading AGP, when build fails due to KMP+AGP incompatibility, or when the user mentions AGP 9.0, android multiplatform plugin, KMP migration, or com.android.kotlin.multiplatform.library.
Kotlin Tooling Cocoapods Spm Migration
Migrate KMP projects from CocoaPods (kotlin("native.cocoapods")) to Swift Package Manager (swiftPMDependencies DSL) — replaces pod() with swiftPackage(), transforms cocoapods.* imports to swiftPMImport.*, and reconfigures the Xcode project.
Kotlin Tooling Java To Kotlin
Use when converting Java source files to idiomatic Kotlin, when user mentions "java to kotlin", "j2k", "convert java", "migrate java to kotlin", or when working with .java files that need to become .kt files. Handles framework-aware conversion for Spring, Lombok, Hibernate, Jackson, Micronaut, Quarkus, Dagger/Hilt, RxJava, JUnit, Guice, Retrofit, and Mockito.
Landing Page Generator
Generates high-converting landing pages as complete Next.js/React (TSX) components with Tailwind CSS. Creates hero sections, feature grids, pricing tables, FAQ accordions, testimonial blocks, and CTA sections using proven copy frameworks (PAS, AIDA, BAB). Outputs SEO meta tags, structured data, and performance-optimised code targeting Core Web Vitals (LCP < 1s, CLS < 0.1). Use when the user asks to create a landing page, marketing page, homepage, single-page site, lead capture page, campaign page, promo page, or conversion-optimised web page — or when they want to A/B test landing page variants or replace a static page with one designed to convert.
Laravel Specialist
Build and configure Laravel 10+ applications, including creating Eloquent models and relationships, implementing Sanctum authentication, configuring Horizon queues, designing RESTful APIs with API resources, and building reactive interfaces with Livewire. Use when creating Laravel models, setting up queue workers, implementing Sanctum auth flows, building Livewire components, optimising Eloquent queries, or writing Pest/PHPUnit tests for Laravel features.
Latch
Proposing, configuring, debugging, and maintaining Claude Code hooks (PreToolUse/PostToolUse/Stop and other lifecycle events). Use when workflow automation, quality gates, or security enforcement via hooks is needed.
Lean Bisect
Bisect Lean toolchain versions to find where behavior changes. Use when trying to identify which Lean 4 commit caused a regression or behavior change.
Lean Mwe
Create minimal working examples (MWEs) from Lean errors for bug reports. Use when minimizing a Lean error, creating an MWE, or preparing a bug report for lean4 or mathlib4.
Legacy Modernizer
Designs incremental migration strategies, identifies service boundaries, produces dependency maps and migration roadmaps, and generates API facade designs for aging codebases. Use when modernizing legacy systems, implementing strangler fig pattern or branch by abstraction, decomposing monoliths, upgrading frameworks or languages, or reducing technical debt without disrupting business operations.
Lens
Comprehending and investigating codebases. Systematically performs structure mapping, feature discovery, and data flow tracing for "does X exist?", "how does Y work?", or "what is this module's responsibility?". Includes a conversational Q&A mode ("ask") for navigator-style, multi-turn questions about a project. Does not write code.
Lighthouse Bridge
Internal helper agent. Invoked by orchestrator agents via Task tool. Internal helper that bridges Lighthouse CI accessibility audit data with the agent ecosystem. Parses Lighthouse reports, normalizes accessibility findings, tracks score regressions, and deduplicates against local scans.
Linear Automation
Automate Linear issue tracking, cycle planning, roadmap management, and engineering workflows
Link Checker
Ambiguous link text checker for web applications. Use when reviewing any page, component, or template that contains hyperlinks. Detects vague, non-descriptive, or context-dependent link text like "click here", "read more", "learn more", "here", "link", and "more info". Enforces WCAG 2.4.4 (Link Purpose in Context) and 2.4.9 (Link Purpose Link Only). Applies to any web framework or vanilla HTML/CSS/JS.
Linting Neostandard Eslint9
Configures ESLint v9 flat config and neostandard for JavaScript and TypeScript projects, including migrating from legacy `.eslintrc*` files or the `standard` package. Use when you need to set up or fix linting with `eslint.config.js` or `eslint.config.mjs`, troubleshoot lint errors, configure neostandard rules, migrate from `.eslintrc` to flat config, or integrate linting into CI pipelines and pre-commit hooks.
Live Region Controller
Live region and dynamic content announcement specialist. Use when building or reviewing any feature that updates content without a full page reload including search results, filters, notifications, toasts, loading states, AJAX responses, form submission feedback, counters, timers, chat messages, progress indicators, or any content that changes after initial page load. Applies to any web framework or vanilla HTML/CSS/JS.
LLM Patterns
AI-first application patterns, LLM testing, prompt management
Ln 001 Push All
Commits and pushes all changes (staged, unstaged, untracked) to remote. Use when you need a quick push of everything at once.
Ln 002 Session Analyzer
Analyzes current or recent session for errors, inefficiencies, and improvement opportunities across skills, tools, hooks, and communication. Use after completing a task or periodically.
Ln 011 Agent Installer
Installs or updates Codex CLI and Claude Code. Use when CLI agents need installation or update.
Ln 013 Config Syncer
Use when installing or verifying this marketplace in Claude and Codex, aligning selected plugins, MCP settings, and Codex execution defaults.
Ln 015 Hex Line Uninstaller
Use when removing Claude-side hex-line integration surfaces such as MCP registration, permissions, hooks, and output style.
Ln 200 Scope Decomposer
Decomposes scope into Epics, Stories, and RICE priorities. Use when user has project scope and wants full Agile breakdown.
Ln 201 Opportunity Discoverer
Discovers growth opportunities using Traffic-First KILL funnel. Use when searching for next product direction with validated demand.
Ln 210 Epic Coordinator
Creates or replans 3-7 Epics from scope using Decompose-First pattern. Use when initiative needs Epic-level breakdown or Epic scope changed.
Ln 221 Story Creator
Creates Story documents with 9-section structure and INVEST validation via the configured tracker provider. Use when Epic has an IDEAL plan ready for Story generation.
Ln 300 Task Coordinator
Analyzes Story and builds optimal task plan (1-8 tasks), then routes to create or replan. Use when Story needs task breakdown or replanning.
Ln 302 Task Replanner
Compares ideal plan vs existing tasks and applies KEEP/UPDATE/OBSOLETE/CREATE changes. Use when Story tasks need re-sync with updated requirements.
Ln 310 Multi Agent Validator
Use when validating Stories, plans, or tasks through the evaluation platform with mandatory research, parallel evidence lanes, sequential merge, and bounded refinement. Modes: story | plan_review.
Ln 311 Review Research Worker
Use when an evaluation run needs mandatory official-doc, MCP Ref, Context7, and current best-practice research with a structured research summary.
Ln 312 Review Findings Worker
Use when an evaluation coordinator needs normalized findings from target artifacts and research evidence.
Ln 313 Review Docs Worker
Use when an evaluation run needs review-driven documentation updates and a structured documentation summary.
Ln 316 Review Refinement Worker
Use when an evaluation run requires bounded iterative refinement with trace and cleanup evidence.
Ln 400 Story Executor
Executes Story tasks in priority order (To Review, To Rework, Todo). Use when Story has planned tasks ready for implementation.
Ln 401 Task Executor
Executes implementation tasks through Todo, In Progress, To Review. Use when task needs coding with KISS/YAGNI. Not for test tasks.
Ln 402 Task Reviewer
Reviews task implementation for quality, code standards, and test coverage. Use when task is in To Review. Sets task Done or To Rework.
Ln 404 Test Executor
Executes test tasks (label 'tests') through Todo to To Review with risk-based limits. Use for test task execution. Not for implementation tasks.
Ln 510 Quality Coordinator
Use when coordinating story quality evaluation with mandatory research, worker summaries, agent review, regression evidence, and bounded refinement.
Ln 511 Code Quality Checker
Checks DRY/KISS/YAGNI/architecture compliance with quantitative Code Quality Score. Use when implementation tasks are Done and need quality scoring.
Ln 512 Tech Debt Cleaner
Auto-fixes low-risk tech debt (unused imports, dead code, commented-out code) with >=90% confidence. Use when audit findings need safe automated cleanup.
Ln 513 Regression Checker
Runs existing test suite to catch regressions after implementation changes. Use when Story needs regression verification. No status changes.
Ln 514 Test Log Analyzer
Analyzes application logs: classifies errors, checks log quality, maps stack traces to source. Use when logs need review after test runs or during development.
Ln 520 Test Planner
Orchestrates test planning pipeline: research, manual testing, automated test planning. Use when Story needs comprehensive test coverage planning.
Ln 521 Test Researcher
Researches real-world problems, competitor solutions, and customer complaints for a feature domain. Use before test planning to ground tests in actual user pain points.
Ln 522 Manual Tester
Performs manual testing of Story AC via executable bash scripts in tests/manual/. Use when Story implementation needs hands-on AC verification.
Ln 523 Auto Test Planner
Plans automated tests (E2E/Integration/Unit) using Risk-Based Testing after manual testing. Use when Story needs a test task with prioritized scenarios.
Ln 611 Docs Structure Auditor
Checks hierarchy, links, SSOT, compression, requirements compliance, freshness, legacy cleanup. Use when auditing documentation structure.
Ln 612 Semantic Content Auditor
Checks document semantic content against SCOPE and project goals, coverage gaps, off-topic content, SSOT. Use when auditing documentation relevance.
Ln 613 Code Comments Auditor
Checks inline code documentation quality: WHY-not-WHAT, density, forbidden content, docstrings quality, actuality, legacy cleanup. Use when auditing comments and docstrings.
Ln 614 Docs Fact Checker
Verifies claims in .md files (paths, versions, counts, configs, endpoints) against codebase, cross-checks contradictions. Use when auditing docs accuracy.
Ln 620 Codebase Auditor
Use when auditing the codebase through the evaluation platform with mandatory research, coordinated domain audit workers, and structured summaries.
Ln 622 Build Delivery Gate Auditor
Checks build, lint, type, test, and CI delivery gate failures. Use when auditing whether the project can reliably ship.
Ln 623 Duplication Overabstraction Auditor
Checks evidence-backed duplication, over-abstraction, and unused extensibility. Use when auditing DRY/KISS/YAGNI risk.
Ln 624 Code Maintainability Hotspot Auditor
Checks local maintainability hotspots: complexity, long methods, god modules, signatures, algorithms, and constants. Also flags identifier drift across API/DTO/DB layers. Use when auditing code hotspots.
Ln 625 Dependency Reuse Auditor
Checks dependency health and generic custom utility/integration replacement opportunities. Use when auditing dependency and reuse risk.
Ln 626 Dead Code Pruning Auditor
Finds code that can be safely deleted: unreachable, unused, obsolete compatibility, and commented-out code. Use when pruning dead code.
Ln 627 Diagnosability Auditor
Checks diagnosability through structured logs, metrics, traces, correlation IDs, and useful log levels. Use when auditing incident visibility.
Ln 628 Concurrency Correctness Auditor
Checks races, deadlocks, async hazards, TOCTOU, blocking I/O, and shared resource contention. Use when auditing concurrency correctness.
Ln 629 Runtime Lifecycle Config Auditor
Checks runtime lifecycle and config validation: bootstrap, shutdown, probes, cleanup, env sync, and fail-fast startup. Use for runtime readiness.
Ln 630 Test Auditor
Use when auditing the test surface through the evaluation platform with mandatory research, coordinated test audit workers, and structured summaries.
Ln 631 Test Business Logic Auditor
Detects tests proving platform behavior instead of local product behavior. Use when auditing product-behavior focus.
Ln 632 Test E2e Priority Auditor
Audits E2E coverage for critical user-visible journeys and wasteful E2E tests. Use when reviewing E2E journey value.
Ln 633 Test Value Auditor
Scores each test by portfolio value and returns KEEP/DELETE/MERGE/REWRITE. Use when pruning test-suite cost.
Ln 634 Test Coverage Auditor
Identifies missing tests for unique critical local logic: money, auth, permissions, data integrity, algorithms, and domain rules. Use when auditing critical logic coverage gaps.
Ln 635 Test Isolation Auditor
Audits whether test results can be trusted: flakiness, isolation, real external dependencies, time/random/order dependency, and shared state. Use when auditing test trustworthiness.
Ln 636 Manual Test Auditor
Audits manual test evidence quality: reproducibility, fail-fast behavior, expected evidence/golden files, idempotency, and documentation. Use when auditing manual tests.
Ln 637 Test Structure Auditor
Audits test maintainability and structure: layout drift, orphan tests, fragmented duplicates, test-to-source mapping, and domain grouping. Use when auditing test suite organization.
Ln 638 Test Oracle Effectiveness Auditor
Audits assertion strength and test oracles that prove real defects. Use when finding weak tests that execute code but prove little.
Ln 640 Pattern Evolution Auditor
Use when auditing architectural patterns through the evaluation platform with mandatory best-practice research, coordinated pattern workers, and structured summaries.
Ln 641 Pattern Fitness Auditor
Audits whether one implemented architectural pattern fits project needs and best practices. Use when checking pattern fitness.
Ln 642 Layer Ownership Boundary Auditor
Checks layer, resource ownership, and orchestration boundaries. Use when auditing architecture boundary enforcement.
Ln 643 API Contract Auditor
Checks layer leakage in method signatures, missing DTOs, entity leakage to API, inconsistent error contracts. Use when auditing API contracts.
Ln 644 Dependency Topology Auditor
Builds dependency topology, detects cycles, validates import rules, and calculates coupling metrics. Use when auditing architecture topology.
Ln 645 Architecture Modernization Auditor
Finds architecture-level modernization opportunities: obsolete custom mechanisms, overbuilt extension points, and simplifiable architecture. Use when auditing architecture evolution.
Ln 646 Project Structure Auditor
Audits physical architecture structure: modules, domains, layer layout, junk drawers, and framework placement. Use for structure drift.
Ln 647 Configuration Boundary Auditor
Audits architecture config boundaries: typed settings, scattered env reads, config leakage, and layer ownership. Use for config architecture.
Ln 651 Query Efficiency Auditor
Checks redundant fetches, N+1 loops, over-fetching, missing bulk operations, wrong caching scope. Use when auditing query efficiency.
Ln 652 Transaction Correctness Auditor
Checks transaction scope, missing rollback handling, long-held transactions, trigger/notify interaction. Use when auditing transaction correctness.
Ln 653 Runtime Performance Auditor
Checks blocking IO in async, unnecessary allocations, sync sleep, string concat in loops, redundant copies. Use when auditing runtime performance.
Ln 654 Resource Lifecycle Auditor
Checks session scope mismatch, missing cleanup, pool config, error path leaks, resource holding. Use when auditing resource lifecycle.
Ln 700 Project Bootstrap
Bootstraps projects to production-ready structure. Use when creating new or transforming existing projects.
Ln 720 Structure Migrator
Scaffolds new or restructures existing projects to Clean Architecture. Use when setting up project structure.
Ln 721 Frontend Restructure
Scaffolds new React projects or restructures monoliths to component-based architecture. Use when setting up frontend structure.
Ln 722 Backend Generator
Generates .NET Clean Architecture backend structure from entity definitions. Use when bootstrapping .NET backend projects.
Ln 723 Seed Data Generator
Generates seed data from ORM schemas or entity definitions to any target format. Use when populating databases for development.
Ln 724 Artifact Cleaner
Removes platform-specific artifacts from Replit, StackBlitz, CodeSandbox, Glitch. Use when preparing exported projects for production.
Ln 740 Quality Setup
Sets up linters, pre-commit hooks, and test infrastructure. Use when adding code quality tooling to a project.