Updates broken JUnit tests after a deliberate code change — distinguishing tests that broke because the behavior changed (update assertion) from tests that broke because they were overcoupled to structure (loosen or delete). Use after API changes, refactors, or intentional behavior changes leave a trail of failing tests.

Generates JUnit regression tests that lock in current behavior before a refactor, capturing observed outputs as assertions so that any behavioral change trips a test. Use before large refactors, when inheriting untested legacy Java, or when the spec is "whatever it does now."

Derives executable test cases directly from requirements (user stories, acceptance criteria, specs) by extracting testable conditions, enumerating equivalence classes and boundaries, and producing a traceability map from each test back to its source requirement. Use when building acceptance tests from a spec, when checking whether requirements are covered by existing tests, when translating Gherkin or plain-English criteria into code, or when proving coverage for compliance.

Advises on rollback strategies by analyzing what a deploy changes — recommending revert, roll-forward, feature-flag kill, or data repair depending on reversibility. Use during an incident when a deploy went bad, when designing a deploy pipeline and the user asks how to make it reversible, or when a migration needs an undo plan.

Generates hardened, multi-stage Dockerfiles with non-root users, minimal base images, and a .dockerignore, after auto-detecting the application stack. Use when containerizing an application for the first time, when the user asks for a Dockerfile, when migrating from a VM deployment, or when an existing Dockerfile runs as root, uses a fat base image, or leaks build tooling into the runtime layer.

Generates configuration files for services and tools (app config, logging config, linter config, database config) from a brief description of desired behavior, matching the target format's idioms. Use when bootstrapping a new service, when the user asks for a config file for a specific tool, or when translating config intent between formats.

Generates deployment pipelines with environment promotion, approval gates, and rollback triggers based on target infrastructure. Use when wiring automated deployments from CI to staging/production, when the user asks for a release pipeline, or when adding promotion gates to an existing deploy workflow.

Applies the SZZ algorithm to VCS history to identify which commits introduced bugs by correlating bug-fix commits with earlier changes. Use when mining a repository for bug-introducing commits, when building a defect-prediction dataset, or when the user asks which commit introduced a given fixed bug.

Finds and safely removes code that is never executed — unreachable branches, uncalled functions, unused classes, dead feature flags. Use when cleaning up after a feature removal, when the user suspects the codebase has accumulated cruft, or when reducing build/bundle size.

Executes refactorings — extract method, inline, rename, move — in small, behavior-preserving steps with a test between each. Use when the user wants to restructure working code, when cleaning up after a feature lands, or when a smell has been identified and needs fixing.

Verifies that a refactoring or transformation preserved observable behavior by comparing before and after execution, differential testing, or I/O capture. Use after a refactoring, after automated code transformation, before merging a structural PR, or whenever the claim is that two code versions do the same thing.

Uses an existing test suite as the behavioral oracle during a migration, tracking which tests pass at each step and localizing regressions to specific migration changes. Use when porting or refactoring code that has tests, when the user wants to migrate incrementally with a safety net, or when a migration broke something and you need to find which step did it.

Translates an entire module or package between languages, handling imports, file layout, visibility, and cross-function dependencies that single-function translation misses. Use when porting a library, when a migration spans multiple files, or when the user hands you a directory and a target language.

Use XcodeBuildMCP to build, run, launch, and debug the current iOS project on a booted simulator. Trigger when asked to run an iOS app, interact with the simulator UI, inspect on-screen state, capture logs/console output, or diagnose runtime behavior using XcodeBuildMCP tools.

Browser automation with persistent named pages via the dev-browser CLI. Use when users ask to navigate websites, fill forms, take screenshots, extract web data, test web apps, log into sites, or automate browser workflows. Trigger phrases include "go to [url]", "click on", "fill out the form", "take a screenshot", "scrape", "automate", "test the website", "log into", "open the browser", or any browser interaction request.

Send Telegram messages, files, and alerts via bot API; read replies; ask questions with inline buttons and wait for the answer (approve-from-phone). Supports multiple bots and named chat targets. Use when the user wants to send a Telegram message or alert, get notified on Telegram when a task finishes or needs input, ask for approval via Telegram, or wire Telegram notifications into hooks, cron jobs, or CI. Triggers: 'telegram', 'send me a telegram', 'alert me on telegram', 'ask me on telegram', 'notify me when done'.

Outsider-perspective end-to-end review of a plan, PR, or code change. First questions intent and whether a simpler/more elegant approach would achieve the same goal, then traces the actual code path (not just the diff) to verify the change does what it claims. Output is concise, actionable, and every call carries its rationale. Trigger on /scrutinize and proactively whenever the user asks to review, audit, sanity-check, or get a second opinion on a plan, PR, diff, design doc, or proposed code change.

Live launchpad feed + AI hot topics for meme tokens. (1) meme-rush: real-time lifecycle feed on launchpads (Pump.fun, Four.meme) — brand-new launches, currently-finalizing / bonding-curve tokens, and just-migrated-to-DEX tokens; filter by dev behavior, age, market cap. (2) topic-rush: AI-detected hot market narratives with the associated tokens ranked by inflow. Use for: "new pump.fun launches", "what just migrated", "currently bonding", "hot narratives", "what topic is pumping right now", "live launchpad feed", "AI hot topics".

Build and deploy Apache Flink user-defined functions (UDFs) in Java for stream processing over Kafka. Use this skill when users want to create scalar UDFs, user-defined table functions (UDTFs), or process table functions (PTFs) in Java, deploy them to Confluent Cloud or local Docker environments, and invoke them from Flink SQL or the Table API. Trigger on: Flink UDF, custom Flink function, process table function, PTF, UDTF, Flink user defined, extend Flink SQL, stateful stream processing with Flink. Do NOT trigger for: Kafka Streams UDFs (use kafka-streams-programming skill), general Flink job development without custom functions, CDC streaming data piplines that include Flink (prefer the confluent-cloud-cdc-tableflow skill), Flink connector setup, or Kafka producer/consumer code.

Use when the user wants to integrate a Kafka client into an existing application or scaffold a Java Kafka client project (Maven or Gradle based) for Confluent Cloud, local Docker, or WarpStream. Covers the Apache Kafka Java clients (KafkaProducer/KafkaConsumer/KafkaShareConsumer) with Avro, JSON Schema, or Protobuf serializers. Also use when the user wants to optimize Java Kafka client configuration for WarpStream. Do NOT trigger for Kafka Streams apps (use kafka-streams-programming), Flink, connectors, or Kafka Python client (use developing-kafka-python-client).