Coding & Development

Build type-safe global state in React with Zustand. Supports TypeScript, persist middleware, devtools, slices pattern, and Next.js SSR with hydration handling. Prevents 6 documented errors. Use when setting up React state, migrating from Redux/Context, or troubleshooting hydration errors, TypeScript inference, infinite render loops, or persist race conditions.

Provides patterns for testing utility classes, static methods, and helper functions. Validates pure functions, null handling, edge cases, and boundary conditions. Generates AssertJ assertions and @ParameterizedTest for string utils, math utils, validators, and collection helpers. Use when testing utils, test helpers, helper functions, static methods, or verifying utility code correctness.

React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing, reviewing, or refactoring React/Next.js code to ensure optimal performance patterns. Triggers on tasks involving React components, Next.js pages, data fetching, bundle optimization, or performance improvements.

Expert guidance for deep learning, transformers, diffusion models, and LLM development with PyTorch, Transformers, Diffusers, and Gradio.

F# testing patterns with xUnit, FsUnit, Unquote, FsCheck property-based testing, integration tests, and test organization best practices.

Implements document chunking, embedding generation, vector storage, and retrieval pipelines for Retrieval-Augmented Generation systems. Use when building RAG applications, creating document Q&A systems, or integrating AI with knowledge bases.

Runs metrics queries against Axiom MetricsDB via scripts. Discovers available metrics, tags, and tag values. Use when asked to query metrics, explore metric datasets, check metric values, or investigate OTel metrics data.

Official Salesforce documentation retrieval guidance. Use when you need authoritative Salesforce docs from developer.salesforce.com or help.salesforce.com, especially when pages are JS-heavy, shell-rendered, or hard to extract with naive fetching.

Generate user-facing release notes from tickets, PRDs, or changelogs. Creates clear, engaging summaries organized by category (new features, improvements, fixes). Use when writing release notes, creating changelogs, announcing product updates, or summarizing what shipped.

Binance Simple-earn request using the Binance API. Authentication requires API key and secret key.

Read-only GitHub triage for issues AND PRs. 1 item = 1 background task (category: quick). Analyzes all open items and writes evidence-backed reports to /tmp/{datetime}/. Every claim requires a GitHub permalink as proof. NEVER takes any action on GitHub - no comments, no merges, no closes, no labels. Reports only. Triggers: 'triage', 'triage issues', 'triage PRs', 'github triage'.

Use when Codex is building or iterating on a web game (HTML/JS) and needs a reliable development + testing loop: implement small changes, run a Playwright-based test script with short input bursts and intentional pauses, inspect screenshots/text, and review console errors with render_game_to_text.

Provides patterns to configure Spring Boot Actuator for production-grade monitoring, health probes, secured management endpoints, and Micrometer metrics across JVM services. Use when setting up monitoring, health checks, or metrics for Spring Boot applications.

Read datasheets and technical PDF documents with `pcb scan`. Use when the user gives a local PDF path or an `http(s)` datasheet/document URL, when a task requires reading, summarizing, extracting information from, or answering questions about a datasheet or technical PDF, or when a KiCad symbol / `.kicad_sym` provides a `Datasheet` property to resolve. Run `pcb scan <input>` in bash, treat stdout as the generated `.md` path, then read that markdown file.

Provides Event-Driven Architecture (EDA) patterns for Spring Boot — creates domain events, configures ApplicationEvent and @TransactionalEventListener, sets up Kafka producers and consumers, and implements the transactional outbox pattern for reliable distributed messaging. Use when implementing event-driven systems in Spring Boot, setting up async messaging with Kafka, publishing domain events from DDD aggregates, or needing reliable event publishing with the outbox pattern.

Expert in Expo React Native TypeScript mobile development with best practices

Plan a VP or CPO 30-60-90 day diagnostic onboarding path. Use when entering a new executive product role and avoiding premature change.

Understand the PM-to-Director transition through altitude and horizon thinking. Use when diagnosing scope, time-horizon, or leadership-level gaps.

작업 중 발견한 인사이트를 구조화된 문서로 축적하여 나만의 지식 베이스를 복리로 성장시킨다

Provides patterns for unit testing JSON serialization/deserialization with Jackson and `@JsonTest`. Validates JSON mapping, custom serializers, date formats, and polymorphic types. Use when testing JSON serialization, validating custom serializers, or writing JSON unit tests in Spring Boot applications.

Provides patterns for unit testing REST controllers using MockMvc and @WebMvcTest. Generates controller tests that validates request/response mapping, validation, exception handling, and HTTP status codes. Use when testing web layer endpoints in isolation for API endpoint testing, Spring MVC tests, mock HTTP requests, or controller layer unit tests.

MySQL and MariaDB schema, query, indexing, transaction, replication, and connection-pool patterns for production backends.

This skill should be used when writing documentation for codebases, including README files, architecture documentation, code comments, and API documentation. Use this skill when users request help documenting their code, creating getting-started guides, explaining project structure, or making codebases more accessible to new developers. The skill provides templates, best practices, and structured approaches for creating clear, beginner-friendly documentation.

Use this skill when upgrading to PixiJS v8 from v7 or diagnosing broken v7 code after an upgrade. Covers async app.init, single pixi.js package (deprecated @pixi/* sub-packages), Graphics shape-then-fill, BaseTexture → TextureSource, shader/uniform rework, ParticleContainer+Particle, constructor options objects, DisplayObject removal, settings/utils removal, Ticker signature, events rewrite. Triggers on: migrate v7, v8 breaking changes, @pixi/ import, DisplayObject, beginFill, endFill, cacheAsBitmap, BaseTexture, deprecated.