Apply web animation principles from Animation at Work by Rachel Nabors. Covers human perception of motion, 12 principles of animation, animation patterns (transitions, supplements, feedback, demonstrations, decorations), CSS transitions, CSS animations, Web Animations API, SVG/Canvas/WebGL, communicating animation with storyboards and motion comps, performance (composite-only properties, will-change, RAIL), accessibility (prefers- reduced-motion, vestibular disorders), and team workflow. Trigger on "animation", "transition", "CSS animation", "keyframe", "easing", "motion design", "web animation", "prefers-reduced-motion", "storyboard", "parallax", "loading animation", "hover effect", "micro-interaction".

Reviews code against Robert C. Martin's Clean Code principles. Use when users share code for review, ask for refactoring suggestions, or want to improve code quality. Produces actionable feedback organized by Clean Code principles with concrete before/after examples.

Generate and review data-intensive application code using patterns from Martin Kleppmann's "Designing Data-Intensive Applications." Use this skill whenever the user asks about data storage engines, replication, partitioning, transactions, distributed systems, batch or stream processing, encoding/serialization, consistency models, consensus, event sourcing, CQRS, change data capture, or anything related to building reliable, scalable, and maintainable data systems. Trigger on phrases like "data-intensive", "replication", "partitioning", "sharding", "LSM-tree", "B-tree", "transaction isolation", "distributed consensus", "stream processing", "batch processing", "event sourcing", "CQRS", "CDC", "change data capture", "serialization format", "schema evolution", "consensus algorithm", "leader election", "total order broadcast", or "data pipeline."

Generate and review Java code using patterns and best practices from Joshua Bloch's "Effective Java" (3rd Edition). Use this skill whenever the user asks about Java best practices, API design, object creation patterns, generics, enums, lambdas, streams, concurrency, serialization, method design, exception handling, or writing clean, maintainable Java code. Trigger on phrases like "Effective Java", "Java best practices", "builder pattern", "static factory", "defensive copy", "immutable class", "enum type", "generics", "bounded wildcard", "PECS", "stream pipeline", "optional", "thread safety", "serialization proxy", "checked exception", "try-with-resources", "composition over inheritance", "method reference", "functional interface", or "Java API design."

Review existing Python code and write new Python code following the 90 best practices from "Effective Python" by Brett Slatkin (2nd Edition). Use when writing Python, reviewing Python code, or wanting idiomatic, Pythonic solutions.

Review existing TypeScript code and write new TypeScript following the 62 items from "Effective TypeScript" by Dan Vanderkam. Use when writing TypeScript, reviewing TypeScript code, working with type design, avoiding any, managing type declarations, or migrating JavaScript to TypeScript. Trigger on: "TypeScript best practices", "type safety", "any", "type assertions", "type design", "strict mode", "TypeScript review", "migrate to TypeScript".

Apply Kotlin In Action practices (Elizarov, Isakova, Aigner, Jemerov, 2nd Ed). Covers Basics (Ch 1-3: functions, extensions, default args), Classes (Ch 4: sealed, data, delegation, companion objects), Lambdas (Ch 5-6: functional APIs, sequences, scope functions), Nullability (Ch 7-8: safe calls, Elvis, platform types, primitives), Conventions (Ch 9: operators, delegated properties), Higher-Order (Ch 10: inline, noinline, crossinline), Generics (Ch 11: variance, reified), Reflection (Ch 12: KClass, KProperty), DSLs (Ch 13: receivers, @DslMarker), Coroutines (Ch 14: structured concurrency, dispatchers, cancellation), Flows (Ch 15: operators, StateFlow, SharedFlow). Trigger on "Kotlin In Action", "Kotlin idiom", "Kotlin coroutine", "Kotlin flow", "Kotlin DSL", "Kotlin generics", "Kotlin null safety", "Kotlin delegation", "Kotlin inline", or "Kotlin extension".

Write and review Rust code using practices from "Programming with Rust" by Donis Marshall. Covers ownership, borrowing, lifetimes, error handling with Result/Option, traits, generics, pattern matching, closures, fearless concurrency, and macros. Use when writing Rust, reviewing Rust code, or learning Rust idioms. Trigger on: "Rust", "ownership", "borrow checker", "lifetimes", "Result", "Option", "traits", "fearless concurrency", ".rs files", "cargo".

Write and review Rust code using systems programming concepts from "Rust in Action" by Tim McNamara. Covers language foundations, ownership and borrowing, smart pointers, data representation (bits, endianness, floats), memory (stack/heap/virtual), file I/O, networking (TCP/HTTP), concurrency (threads/closures), and OS-level programming. Use when writing systems-level Rust, working with binary data, raw pointers, file formats, network protocols, or low-level memory. Trigger on: "Rust", "systems programming", "smart pointers", "endianness", "bit manipulation", "TCP", "raw pointers", "serde", "borrow checker", "ownership", "concurrency", "kernel", ".rs files", "cargo".

Write and review Spring Boot applications using practices from "Spring Boot in Action" by Craig Walls. Covers auto-configuration, starter dependencies, externalizing configuration with properties and profiles, Spring Security, testing with MockMvc and @SpringBootTest, Spring Actuator for production observability, and deployment strategies (JAR, WAR, Cloud Foundry). Use when building Spring Boot apps, configuring beans, writing integration tests, setting up health checks, or deploying to production. Trigger on: "Spring Boot", "Spring", "@SpringBootApplication", "auto-configuration", "application.properties", "application.yml", "@RestController", "@Service", "@Repository", "SpringBootTest", "Actuator", "starter", ".java files", "Maven", "Gradle".

Apply data visualization and storytelling principles from Storytelling with Data by Cole Nussbaumer Knaflic. Covers choosing effective visuals (line, bar, table, scatterplot), eliminating clutter (Gestalt principles, data-ink ratio), focusing attention (preattentive attributes, strategic color), thinking like a designer (affordances, alignment, white space), and narrative structure (three-act story, horizontal/vertical logic, Big Idea). Trigger on "data visualization", "chart design", "dashboard design", "data storytelling", "presentation chart", "declutter chart", "bar chart", "line chart", "data narrative", "slide deck data", "chart review", "viz critique", "storytelling with data".

Apply system design principles from System Design Interview by Alex Xu. Covers scaling (load balancing, DB replication, sharding, caching, CDN), estimation (QPS, storage, bandwidth), the 4-step framework, and 12 real designs: rate limiter, consistent hashing, key-value store, unique ID generator, URL shortener, web crawler, notification system, news feed, chat system, search autocomplete, YouTube, Google Drive. Trigger on "system design", "scale", "high-level design", "distributed system", "rate limiter", "consistent hashing", "back-of-envelope", "QPS", "sharding", "load balancer", "CDN", "cache", "message queue", "web crawler", "news feed", "chat system", "autocomplete", "URL shortener".

You are an expert startup strategy advisor grounded in the 14 chapters from *The Lean Startup* (How Today's Entrepreneurs Use Continuous Innovation to Create Radically Successful Businesses) by Eric Ries. You help in two modes:

Apply Using Asyncio in Python practices (Caleb Hattingh). Covers Introducing Asyncio (Ch 1: what it is, I/O-bound concurrency), Threads (Ch 2: drawbacks, race conditions, GIL, ThreadPoolExecutor), Asyncio Walk-Through (Ch 3: event loop, coroutines, async def/await, tasks, futures, gather, wait, async with, async for, async comprehensions, startup/shutdown, signal handling, executors), Libraries (Ch 4: aiohttp, aiofiles, Sanic, aioredis, asyncpg), Concluding Thoughts (Ch 5), History (App A: generators to async/await), Supplementary (App B). Trigger on "asyncio", "async/await", "event loop", "coroutine", "aiohttp", "async Python", "concurrent I/O", "non-blocking".

Apply Web Scraping with Python practices (Ryan Mitchell). Covers First Scrapers (Ch 1: urllib, BeautifulSoup), HTML Parsing (Ch 2: find, findAll, CSS selectors, regex, lambda), Crawling (Ch 3-4: single-domain, cross-site, crawl models), Scrapy (Ch 5: spiders, items, pipelines, rules), Storing Data (Ch 6: CSV, MySQL, files, email), Reading Documents (Ch 7: PDF, Word, encoding), Cleaning Data (Ch 8: normalization, OpenRefine), NLP (Ch 9: n-grams, Markov, NLTK), Forms & Logins (Ch 10: POST, sessions, cookies), JavaScript (Ch 11: Selenium, headless, Ajax), APIs (Ch 12: REST, undocumented), Image/OCR (Ch 13: Pillow, Tesseract), Avoiding Traps (Ch 14: headers, honeypots), Testing (Ch 15: unittest, Selenium), Parallel (Ch 16: threads, processes), Remote (Ch 17: Tor, proxies), Legalities (Ch 18: robots.txt, CFAA, ethics). Trigger on "web scraping", "BeautifulSoup", "Scrapy", "crawler", "spider", "scraper", "parse HTML", "Selenium scraping", "data extraction".