coreyja.com

Design and implement RESTful API endpoints following REST principles, consistent naming conventions, and proper HTTP methods. Use this skill when creating or modifying API routes, controllers, or handlers in backend code. When implementing endpoint logic that handles HTTP requests (GET, POST, PUT, PATCH, DELETE). When working with API versioning, query parameters, or response formatting. When defining URL structures for resource-based endpoints. When setting up rate limiting or HTTP status code handling. When working with files like route definitions, controller files, API handler modules, or web framework configuration files.

Create and manage database migrations with proper rollback methods, focused changes, and zero-downtime deployment considerations. Use this skill when creating new database migration files, modifying table schemas, adding or removing columns, creating or dropping indexes, or managing database version control. When working with migration directories, schema definition files, or database change scripts. When implementing backwards-compatible database changes for production deployments. When separating schema changes from data migrations.

Define database models with clear naming, appropriate data types, proper constraints, and relationship definitions. Use this skill when creating or modifying ORM model files, database entity definitions, or data structure schemas. When defining table relationships, foreign keys, and cascade behaviors. When implementing model validation rules, timestamps, or indexes. When working with model files in frameworks like SQLAlchemy, Sequelize, ActiveRecord, SQLx, Prisma, or similar ORMs. When choosing appropriate data types for columns or establishing data integrity constraints (NOT NULL, UNIQUE, foreign keys).

Write secure, performant database queries using parameterized statements, proper indexing, and query optimization techniques. Use this skill when writing SQL queries, ORM query methods, or database access code. When implementing data fetching logic that retrieves or updates database records. When optimizing queries to prevent N+1 problems through eager loading or joins. When using WHERE clauses, JOIN operations, or ORDER BY statements. When implementing transactions for related database operations. When working with query builder methods, raw SQL, or ORM query interfaces. When setting query timeouts or implementing query result caching.

Build accessible user interfaces with semantic HTML, proper ARIA attributes, keyboard navigation, and screen reader compatibility. Use this skill when creating or modifying HTML markup, UI components, forms, or interactive elements. When implementing keyboard navigation, focus management, or tab order. When adding alternative text for images or labels for form inputs. When ensuring sufficient color contrast ratios. When working with navigation menus, modals, buttons, or dynamic content. When structuring pages with proper heading hierarchy (h1-h6). When testing UI changes for screen reader compatibility.

Design reusable, composable UI components with single responsibility, clear interfaces, and proper state management. Use this skill when creating or refactoring React, Vue, Svelte, or other framework components. When defining component props, interfaces, or APIs. When managing component state or lifting state up to parent components. When building reusable UI elements like buttons, cards, forms, modals, or lists. When implementing component composition patterns. When working with component files (.jsx, .tsx, .vue, .svelte). When documenting component usage or creating component libraries.

Write maintainable CSS following the project's established methodology, whether using Tailwind utility classes, BEM naming, CSS modules, or styled-components. Use this skill when styling UI components or pages with CSS, applying design system tokens for colors and spacing, or working with CSS frameworks. When writing utility classes, custom styles, or responsive design rules. When working with .css, .scss, .module.css files, or inline styles in JSX/templates. When establishing or maintaining design tokens for consistent styling. When optimizing CSS for production builds with purging or tree-shaking unused styles.

Build responsive layouts that work seamlessly across mobile, tablet, and desktop screen sizes using mobile-first development, fluid layouts, and relative units. Use this skill when implementing layouts or UI components that need to adapt to different screen sizes. When setting up breakpoints, media queries, or responsive utilities. When using relative units (rem, em, %) instead of fixed pixels. When ensuring touch-friendly tap targets and optimizing for mobile performance. When testing UI changes across multiple device sizes. When implementing responsive typography, images, or navigation patterns.

Maintain consistent code formatting, naming conventions, and structure across the entire codebase with automated tools and clear standards. Use this skill when writing any code in any language or framework. When naming variables, functions, classes, or files. When formatting code with proper indentation and line breaks. When refactoring code to remove duplication or extract reusable functions. When running linters or formatters to ensure consistency. When removing dead code, unused imports, or commented-out blocks. When applying DRY principles to avoid code duplication. This skill applies universally to all programming tasks.

Write self-documenting code with clear naming and structure, adding minimal, evergreen comments only when necessary to explain complex logic. Use this skill when writing or reviewing any code that might need comments. When refactoring code to make it more self-explanatory through better naming and structure. When deciding whether to add or remove comments from existing code. When ensuring comments explain why something is done rather than what is being done. When reviewing code to remove outdated or temporary change-related comments. This skill applies to all programming languages and all types of code files.

Follow established project structure, version control practices, documentation standards, and development workflows to maintain consistency across the team. Use this skill when organizing files and directories in a project. When writing README documentation or contributing guidelines. When creating git commits with clear messages or pull request descriptions. When managing environment configuration or dependencies. When setting up feature flags or maintaining changelogs. When establishing code review processes or testing requirements. This skill applies to all project management and development workflow tasks.

Implement robust error handling with user-friendly messages, specific exception types, centralized error boundaries, and graceful degradation strategies. Use this skill when implementing error handling logic in any part of the application. When writing try-catch blocks, error boundaries, or exception handlers. When validating input and failing fast with clear error messages. When handling API errors, network failures, or external service timeouts. When implementing retry strategies with exponential backoff. When ensuring resources are properly cleaned up in finally blocks. When displaying error messages to users without exposing technical details. This skill applies to all error handling across frontend and backend code.

Reference and maintain knowledge of the project's technical stack including frameworks, languages, databases, testing tools, and third-party services. Use this skill when making architectural decisions about which technologies to use. When adding new dependencies or integrating third-party services. When setting up development environments or deployment infrastructure. When choosing between different libraries or frameworks for a feature. When documenting the technology choices made in the project. When onboarding new team members to understand the tech stack. This skill helps ensure technology choices align with the established stack and provides a reference for all technical decisions.

Implement secure, comprehensive input validation on both client and server sides using allowlists, type checking, and sanitization to prevent injection attacks. Use this skill when handling user input from forms, API requests, or any external data source. When implementing form validation logic with field-specific error messages. When validating data types, formats, ranges, and required fields. When sanitizing input to prevent SQL injection, XSS, or command injection. When validating business rules like sufficient balance or valid date ranges. When implementing both client-side validation for user experience and mandatory server-side validation for security.

Write focused tests for core user flows and critical business logic, testing behavior rather than implementation, with clear names and fast execution. Use this skill when writing unit tests, integration tests, or end-to-end tests. When testing critical user workflows and primary application features. When creating tests that focus on what code does rather than how it does it. When mocking external dependencies like databases, APIs, or file systems. When naming tests to clearly describe the scenario and expected outcome. When keeping tests fast and independent. When completing feature implementation and adding strategic tests at logical completion points. When working with test files or test frameworks.