2,373 free skills
Skills for writing and running tests — framework-specific patterns for Jest, Vitest, pytest, Go testing, RSpec, JUnit, Playwright, Cypress, and more.
Sourced from real, public repositories — synced daily, never invented.
15 tools across six categories
13 of them never send your data anywhere
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golang-pro
compozy/skeeper
Implements concurrent Go patterns using goroutines and channels, designs and builds microservices with gRPC or REST, optimizes Go application performance with pprof, and enforces idiomatic Go with generics, interfaces, and robust error handling. Use when building Go applications requiring concurrent programming, microservices architecture, or high-performance systems. Invoke for goroutines, channels, Go generics, gRPC integration, CLI tools, benchmarks, or table-driven testing.
ruby
nimadorostkar/claude-skills-collection
Use when writing Ruby or working in Rails codebases. Covers idiomatic object design, service objects, ActiveRecord query performance, RSpec structure, and RuboCop-clean style.
rspec-matchers
bastos/ruby-plugin-marketplace
This skill should be used when the user asks about "RSpec matchers", "expect syntax", "custom matchers", "compound matchers", "should vs expect", mentions "eq", "be", "include", "match", "have_attributes", or needs guidance on RSpec assertions and expectations.
language-ruby
lugassawan/swe-workbench
Ruby idioms — Ruby 3.x pattern matching, blocks, procs, lambdas, Enumerable, Comparable, frozen string literals, error handling, and testing. Auto-load when working with .rb files, Gemfile, Rakefile, gemspecs, or when the user mentions Ruby, Bundler, RSpec, minitest, blocks, procs, lambdas, or pattern matching.
moai-lang-ruby
jg-chalk-io/nora-livekit
Ruby 3.4+ best practices with RSpec 4, RuboCop 2, Bundler, and Rails
PHP
clawic/skills
Writes, debugs, and reviews PHP: type juggling, arrays, OOP, Composer, PDO, sessions, PHP-FPM, OPcache, PHP 8 features. Use when PHP returns a blank white page or a 500 with no message, when "headers already sent", "Allowed memory size exhausted", "Maximum execution time exceeded", "Class not found" after a Composer install, or an undefined array key warning appears; when `==` compares wrong, `strpos` or `preg_match` returns a falsy match, accents turn into mojibake, `DateTime` shifts by a day or an hour, `json_encode` returns false, PDO refuses to bind a parameter or emulates prepares, sessions serialize parallel AJAX requests, nginx answers 502 or 504 in front of PHP-FPM, OPcache keeps serving old code, or a version upgrade breaks on deprecations. Also for escaping output, hashing passwords, sizing FPM workers, writing PHPUnit tests, and clearing PHPStan errors. Not for framework internals — `laravel` covers Eloquent, queues, and Laravel auth.
php-testing
marvinrichter/clarc
PHP testing patterns: PHPUnit 11 with mocks and data providers, Pest v3 with expectations and datasets, Laravel feature/HTTP tests with RefreshDatabase, Symfony WebTestCase, PHPStan static analysis, Infection mutation testing. Use when writing or reviewing PHP tests.
javascript
ven0m0/claude-config
JavaScript specialist for Node.js, Bun, and Deno with modern async patterns, API development, testing, and lint/format workflows. Use when building or refactoring JavaScript applications.
edge-patterns
marvinrichter/clarc
Edge Computing patterns: Cloudflare Workers (Durable Objects, KV, D1, R2, Wrangler), Vercel Edge Middleware (geo-routing, A/B testing, Edge Config), Deno Deploy, edge runtime constraints (no fs/child_process, bundle limits), streaming responses, edge caching (Cache API, stale-while-revalidate), and testing with Miniflare.
Bun
bun/sh
Use when building, running, testing, or bundling JavaScript/TypeScript applications. Reach for Bun when you need to execute scripts, manage dependencies, run tests, or bundle code for production. Bun is a drop-in replacement for Node.js with integrated package manager, test runner, and bundler.
django-cotton
samueljennings/django-cotton-bs5
Expert guide for working with Django Cotton, a component-based UI composition library. Use when creating, modifying, or testing Cotton components — covers component syntax, slots (default and named), attributes, c-vars, dynamic attributes with Python types, attribute proxying, template organization, naming conventions, and integration patterns. Essential for building reusable UI components in Django templates.
django
nimadorostkar/claude-skills-collection
Use when building Django applications. Covers ORM query performance, model design, migrations, Django REST Framework, security defaults, and testing.
django-cotton
fair-dm/fairdm
Expert guide for working with Django Cotton, a component-based UI composition library. Use when creating, modifying, or testing Cotton components — covers component syntax, slots (default and named), attributes, c-vars, dynamic attributes with Python types, attribute proxying, template organization, naming conventions, and integration patterns. Essential for building reusable UI components in Django templates.
django-pro
mathewgeejo/agent-skills
Master Django 5.x with async views, DRF, Celery, and Django Channels. Build scalable web applications with proper architecture, testing, and deployment.
django-new-api
criscandv/cdv-skills
Scaffold a brand-new Django + DRF REST API project from scratch, with the full house baseline already wired — settings split, custom user, UUID/soft-delete abstract models, request-context middleware, domain exceptions + global handler, custom pagination, the standard response renderer, dual JWT + API-key auth, drf-spectacular docs, ruff + pre-commit + pytest. Use this skill when the user asks to start, bootstrap, create or initialise a new Django/DRF backend or API project. Trigger on phrases like "new Django project", "start a Django API", "bootstrap a backend", "monta un proyecto Django desde cero". This is a slash-invoked action; for editing an existing project's conventions use django-normalize, and for adding a feature to an existing project use django-feature.
spring-testing-router
spring-ai-community/spring-testing-skills
Use this skill proactively before writing any Spring test code — even without an explicit request. Triggers: about to create test files for a Spring Boot project, writing a JUnit test suite, implementing test coverage for a Spring application, or whenever the user mentions writing Spring tests. Do not wait for the user to name a specific slice annotation. Routes to: spring-jpa-testing (JPA repositories, org.springframework.boot.data.jpa.test.autoconfigure.DataJpaTest, org.springframework.data.jpa.repository.JpaRepository), spring-mvc-testing (org.springframework.boot.webmvc.test.autoconfigure.WebMvcTest, org.springframework.test.web.servlet.MockMvc, REST controllers), spring-security-testing (org.springframework.security.test.context.support.WithMockUser, CSRF, JWT, OAuth2), spring-webflux-testing (org.springframework.boot.webflux.test.autoconfigure.WebFluxTest, org.springframework.test.web.reactive.server.WebTestClient, reactor.test.StepVerifier), spring-websocket-testing (STOMP, SockJS, WebSocket messaging), spring-testing-fundamentals (org.assertj.core.api.Assertions, org.mockito.BDDMockito, testing pyramid, context caching).
spring-boot-expert
ricardolv/spring-ai-plugins
Expert Spring Boot backend development guidance. Use when creating JPA entities, Spring Data repositories, REST controllers, security configurations, or optimizing database performance; implementing authentication; writing tests with JUnit/Testcontainers; or working with Spring Boot 4.0. Follows Spring Boot best practices and modern Java patterns.
terraform-engineer
wesleyegberto/software-engineering-skills
Use when implementing infrastructure as code with Terraform across AWS, Azure, or GCP. Invoke for module development, state management, provider configuration, multi-environment workflows, infrastructure testing.
ansible-validator
gitjfmd/ansible-skills
Comprehensive toolkit for validating, linting, testing, and automating Ansible playbooks, roles, and collections. Use this skill when working with Ansible files (.yml, .yaml playbooks, roles, inventories), validating automation code, debugging playbook execution, performing dry-run testing with check mode, or working with custom modules and collections.
netlify-database
practicalswan/agent-skills
Zero-config Postgres for Netlify apps via @netlify/database — querying data from Functions/Edge Functions, writing schema migrations, setting up Drizzle ORM, local dev with netlify dev, database branches for deploy previews, and migrating an existing Postgres project onto Netlify. Use when adding a database, building a contact form or CRUD API, writing SQL migrations, wiring up Drizzle, running netlify database commands, testing with a local Postgres, or switching from Neon/Supabase/RDS to Netlify Database.
netlify-functions
practicalswan/agent-skills
Write, configure, and deploy Netlify serverless functions in TypeScript, JavaScript, or Go. Use this when adding an API endpoint or backend route, adding a contact form handler, wiring auth or Identity signup/login hooks, building streaming or AI-proxy responses, scheduling cron jobs, running long background jobs (batch processing/scraping), reacting to deploy or form events, setting up rate limiting or region/memory config, or reading environment variables and secrets inside a function. Covers file locations, the Request/Context/Response handler shape, path routing, config options, and local testing with netlify dev.
netlify-edge-functions
practicalswan/agent-skills
Write, configure, and deploy Netlify Edge Functions (Deno runtime at the network edge) in TypeScript/JavaScript. Use when adding request/response manipulation at the edge — auth middleware, geolocation redirects, A/B testing and personalization, content localization, redirects/rewrites, SSR at the edge, or transforming responses — or when configuring path routing, response caching, or edge error handling. Triggers on tasks like \"add auth middleware\", \"geo-based redirect\", \"A/B testing at the edge\", \"rewrite requests\", or editing files in netlify/edge-functions.
bilibili-video-evidence
rookiecuzz/codex-bilibili-skills
Collect evidence artifacts from a Bilibili video URL. Fetch native subtitles, save `sectioned.md`, write normalized `subtitles.json`, capture `frames/*.png`, optionally validate a repo-local screenshot endpoint with `smoke-report.json`, and fall back to a local `ffmpeg` + ASR workflow when a page exposes no usable subtitle track. Use when Codex needs a Bilibili evidence bundle from `videoUrl`, direct frame capture by timestamp, subtitle download, transcript sectioning, local subtitle generation as `.srt`, Chinese subtitle translation that preserves technical keywords, screenshot endpoint smoke testing, or login-gated subtitle handling.
mongodb-pentest
abelrguezr/hacktricks-skills
Security assessment and penetration testing for MongoDB databases. Use this skill whenever the user needs to enumerate MongoDB instances, test for authentication bypass, check for ObjectID prediction vulnerabilities, assess MongoBleed (CVE-2025-14847) exposure, or perform authorized security testing on MongoDB services on ports 27017/27018. Trigger for any MongoDB security assessment, vulnerability scanning, or penetration testing task.
redis-pentesting
abelrguezr/hacktricks-skills
Pentest Redis instances (port 6379) for enumeration, authentication bypass, data exfiltration, and RCE. Use this skill whenever the user mentions Redis, port 6379, key-value stores, in-memory databases, or needs to test Redis security. This includes checking for authentication, dumping databases, exploiting misconfigurations, and testing for known CVEs like CVE-2025-49844, CVE-2025-46817, CVE-2025-46818.
pentest-kibana
abelrguezr/hacktricks-skills
How to pentest Kibana instances on port 5601. Use this skill whenever you need to assess Kibana security, enumerate Kibana services, check for authentication bypass, explore Elasticsearch data through Kibana, or identify vulnerabilities in the Elastic Stack. Trigger this skill for any Kibana-related security assessment, port 5601 enumeration, or Elastic Stack penetration testing.
rabbitmq-pentest
abelrguezr/hacktricks-skills
Pentest RabbitMQ Management interfaces on port 15672. Use this skill whenever you need to assess RabbitMQ security, test default credentials, enumerate via the management API, publish messages to queues, or crack RabbitMQ authentication hashes. Trigger this for any RabbitMQ exposure, AMQP service testing, or when you see port 15672 open.
spring-kafka-event-integration
amritmalla/claude-full-stack-2.0
Use when adding, reviewing, or hardening Kafka producers, consumers, or event-driven flows in a Spring Boot service after backend architecture has defined the event contracts. Produces Spring Kafka producer and consumer configuration, serialization and schema-registry posture, idempotency and exactly-once delivery decisions, retry and dead-letter topology, transactional outbox wiring, consumer group and rebalance behavior, error and poison-pill handling, observability for event flows, and integration test scaffolding with embedded or Testcontainers Kafka. Do not use for event contract design, broker provisioning, non-Kafka brokers (RabbitMQ, Pulsar, SQS), or general async/scheduled work; use backend-architecture, infrastructure-platform, or spring-boot-service-scaffold instead.
celery-tests
testland/qa
Authors and runs Celery task tests in Python - `pytest-celery` fixtures (`celery_app`, `celery_worker` per-test, `celery_session_worker` per-session); `task_always_eager` config NOT recommended for unit tests; `apply()` for synchronous test invocation; mock-and-patch retry patterns via `unittest.mock.patch` on `task.retry`. Use when the user works with Celery task workers and needs unit / integration tests across function-style or class-style tasks.
develop-and-test
onedro1d/dark-factory
Autonomous development and integration testing from a requirements doc. Implements everything — database changes, contracts, handlers, configuration — then tests against real infrastructure (dev DB, dev RabbitMQ). Verifies by emitting events, checking DB state, reading logs, and checking error tables. Triggers on "develop this", "implement this", "build from requirements", "start development", "execute the plan", "build and test".
golang-grpc
opentritium/myskills
Provides gRPC usage guidelines, protobuf organization, and production-ready patterns for Golang microservices. Use when implementing, reviewing, or debugging gRPC servers/clients, writing proto files, setting up interceptors, handling gRPC errors with status codes, configuring TLS/mTLS, testing with bufconn, or working with streaming RPCs.
grpc-architect
ralvarezdev/ralvaskills
Vanilla gRPC standards — .proto services, status.Error with standard codes, domain→code mapping, interceptor chain (auth/log/recovery/validation/metrics), client deadlines, context propagation, reflection off in prod, bufconn testing. Language-agnostic; Go examples. Use when designing or reviewing a gRPC service.
spring-boot-grpc
ricardolv/spring-ai-plugins
Expert guidance for building gRPC services with Spring Boot 4 using Spring gRPC. Use when defining protobuf schemas and generating Java stubs; implementing gRPC servers with @GrpcService; creating gRPC clients with @GrpcClient; configuring server/client interceptors; setting up SSL/TLS or Spring Security on gRPC; implementing streaming RPCs; adding health checks, reflection, or observability; or testing gRPC endpoints. Follows Spring gRPC patterns and protobuf best practices.
playwright-trace
joaoprocopio/skills
Inspect Playwright trace files from the command line — list actions, view requests, console, errors, snapshots and screenshots.
oauth-pentest
abelrguezr/hacktricks-skills
Security testing for OAuth 2.0 and OIDC implementations. Use this skill whenever the user mentions OAuth, authentication flows, account takeover, identity providers, SSO, login flows, authorization codes, access tokens, or any security testing related to third-party authentication. This skill helps identify vulnerabilities like open redirect_uri, CSRF state issues, token leakage, client secret exposure, and other OAuth misconfigurations that lead to account compromise.
product-discovery
roger-235/my_skill_repo
Use when validating product opportunities, mapping assumptions, planning discovery sprints, or testing problem-solution fit before committing delivery resources.
github-actions-dataops
ivanshamaev/de-agent-skills
Use when building or reviewing GitHub Actions CI/CD pipelines for data engineering — covering dbt slim CI (state:modified+, --defer, manifest.json), SQLFluff SQL linting with PR annotations, Airflow DAG integrity tests (pytest/DagBag), Great Expectations and Soda data quality gates, multi-stage Docker image builds for Spark/dbt/Airflow pushed to ghcr.io, secrets management with OIDC for AWS/GCP (no static keys), environment-scoped secrets, reusable workflows (workflow_call), matrix builds, composite actions, and full end-to-end dbt project CI/CD workflows.
new-project-setup
nrakow/ae-skills-dev
End-to-end setup for a new analytics engineering project from blank slate to production-ready dbt project. Sequences: data-stack-context, dbt-project-setup, sql-style-guide, data-modeling, data-quality-testing, dbt-ci-cd. Triggers: 'new analytics project', 'start analytics engineering', 'set up from scratch', 'brand new dbt project', 'analytics engineering setup', 'bootstrap analytics'.
dbt-transformation-patterns
leandropreda16/opencode-skills
Master dbt (data build tool) for analytics engineering with model organization, testing, documentation, and incremental strategies. Use when building data transformations, creating data models, or implementing analytics engineering best practices.
mobile-testing
tmhsdigital/mobile-app-developer-tools
Set up unit and integration testing for React Native/Expo or Flutter apps. Covers Jest, React Native Testing Library, flutter_test, snapshot testing, mocking native modules, and test organization. Use when the user wants to add or improve tests for components, hooks, or business logic.
android-kotlin-expert
trancee/meshlink
Expert help for Android app development in Kotlin, including app architecture, ViewModel/state, coroutines and Flow, Jetpack Compose, Gradle/AGP/Kotlin compatibility, testing, and Java-to-Kotlin migration. Use this skill whenever the user asks to write, debug, review, refactor, explain, or set up Android Kotlin code or Android build tooling, even if they mention only Compose, ViewModel, Flow, lifecycle, `build.gradle.kts`, Android Studio, AGP, coroutines, Room, or tests rather than explicitly saying 'Kotlin' or 'Android architecture'.
bc-golden-testing
bancolombia/bc_golden_plugin
Expert guidance for creating visual regression tests using bc_golden_plugin for Flutter applications
qa-browser-testing
feliperyba/ralph-orchestra
E2E test creation and execution for QA. Validates implementations using Playwright API tests that become persistent artifacts for regression.
blog-writer
broedkrummen/openclaw-skills
This skill should be used when writing blog posts, articles, or long-form content in the writer's distinctive writing style. It produces authentic, opinionated content that matches the writer's voice—direct, conversational, and grounded in personal experience. The skill handles the complete workflow from research review through Notion publication. Use this skill for drafting blog posts, thought leadership pieces, or any writing meant to reflect the writer's perspective on AI, productivity, sales, marketing, or technology topics.
blog-writer
choupiyang/zai_skills
This skill should be used when writing blog posts, articles, or long-form content in the writer's distinctive writing style. It produces authentic, opinionated content that matches the writer's voice—direct, conversational, and grounded in personal experience. The skill handles the complete workflow from research review through Notion publication. Use this skill for drafting blog posts, thought leadership pieces, or any writing meant to reflect the writer's perspective on AI, productivity, sales, marketing, or technology topics.
translatable-development
spatie/laravel-translatable
Use when working with spatie/laravel-translatable. Trigger when the query mentions translatable models, translations, multi-language attributes, the HasTranslations trait, the #[Translatable] attribute, or storing translations as JSON on Eloquent models. Tasks include making a model translatable, writing migrations for translatable columns, setting translations for specific locales, getting translations (with or without fallbacks), querying by locale, handling missing translations, and testing translatable behavior.
broken-yaml-skill
yaojingang/yao-meta-skill
Broken YAML fixture for packager failure testing.
redos-pentest
abelrguezr/hacktricks-skills
Use this skill whenever you need to identify, test, or exploit Regular Expression Denial of Service (ReDoS) vulnerabilities. Trigger this skill when analyzing regex patterns for security issues, testing web applications for ReDoS, generating ReDoS payloads, or auditing code for vulnerable regex patterns. Use it for CTF challenges, bug bounty hunting, or security assessments involving regular expressions.
rust-testing
omkarop0808/neofuture
Rust testing patterns including unit tests, integration tests, async testing, property-based testing, mocking, and coverage. Follows TDD methodology.
boxlang-google-cloud-functions
ortus-boxlang/skills
Use this skill when building, testing, or deploying BoxLang applications on Google Cloud Functions Gen 2, including handler structure, FunctionRunner entry point, URI routing, environment variables, local development with the GCF invoker, and debugging.
boxlang-aws-lambda
ortus-boxlang/skills
Use this skill when building, deploying, or debugging BoxLang applications on AWS Lambda — including Lambda.bx structure, handler conventions, environment variables, SAM CLI testing, performance optimization, connection pooling, multi-function routing, and the boxlang-starter-aws-lambda project.
poku
pokujs/skills
Use when writing, running, or debugging tests with Poku — a cross-runtime test runner for Node.js, Bun, and Deno. Covers assertions, describe/it blocks, background services, watch mode, configuration, CLI flags, and patterns for integration and e2e tests.
cz-perspective
sac-y/cz-skill
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rust-testing
sydonayrex/tldr
|
rust-testing
jamkris/everything-gemini-code
Rust testing patterns including unit tests, integration tests, async testing, property-based testing, mocking, and coverage. Follows TDD methodology.
rust-testing
kunanonj/ai-skills-hub
Rust testing patterns including unit tests, integration tests, async testing, property-based testing, mocking, and coverage. Follows TDD methodology.
supabase
n1majne3/strix
Supabase security testing covering Row Level Security, PostgREST, Edge Functions, and service key exposure
testing
89jobrien/langchainx
JOB-257 — FakeLLM, in-process test doubles, writing offline chain/agent tests.
agent-browser
rivet-dev/sandbox-agent
Browser automation CLI for AI agents. Use when the user needs to interact with websites, including navigating pages, filling forms, clicking buttons, taking screenshots, extracting data, testing web apps, or automating any browser task. Triggers include requests to "open a website", "fill out a form", "click a button", "take a screenshot", "scrape data from a page", "test this web app", "login to a site", "automate browser actions", or any task requiring programmatic web interaction.
kafka-strimzi-operator
lurodrisilva/personal-skills
MUST USE when authoring, reviewing, deploying, sizing, tuning, or **performance-testing** anything involving **Apache Kafka on Kubernetes via the Strimzi operator** — including Strimzi Cluster Operator, Topic Operator, User Operator, Drain Cleaner, the `Kafka` / `KafkaNodePool` / `KafkaTopic` / `KafkaUser` / `KafkaConnect` / `KafkaConnector` / `KafkaMirrorMaker2` / `KafkaBridge` / `KafkaRebalance` / `StrimziPodSet` custom resources; KRaft-only deployments (controllers + brokers as separate node pools, ZooKeeper is removed in Kafka 4.0+); listener types (`internal`, `cluster-ip`, `nodeport`, `loadbalancer`, `ingress`, `route`); broker storage choices (`ephemeral`, `persistent-claim`, `jbod`) and `storageClass` selection (Premium SSD v2, gp3, hyperdisk); JVM tuning (`spec.jvmOptions.-Xms/-Xmx`, GC); resource requests/limits and how they MUST line up with `cruiseControl.brokerCapacity.cpu` / `inboundNetwork` / `outboundNetwork`; the **exact `BrokerCapacity` schema** (`cpu` matching `^[0-9]+([.][0-9]{0,3}|[m]?)$`, `inboundNetwork`/`outboundNetwork` matching `^[0-9]+([KMG]i?)?B/s$`, plus per-broker `overrides` carrying `brokers` as `List<Integer>`); Cruise Control optimisation goals, anomaly detectors, and `KafkaRebalance` modes (`full`, `add-brokers`, `remove-brokers`, `rebalance-disks`); FeatureGates including `KafkaNodePools` (default true 0.46+) and unidirectional Topic Operator; rack awareness via `spec.rack.topologyKey`; pod placement (`affinity`, `tolerations`, `topologySpreadConstraints`); the canonical `entityOperator` block carrying `topicOperator` and `userOperator`; PodDisruptionBudgets and `Drain Cleaner` for safe rolling updates; metrics via `kafka-metrics` ConfigMap, JMX exporter on port 9404, the Strimzi Metrics Reporter, and `KafkaUser` quotas (`producerByteRate`, `consumerByteRate`, `requestPercentage`, `controllerMutationRate`); install via `install/cluster-operator/*.yaml`, the `oci://quay.io/strimzi-helm/strimzi-kafka-operator` Helm chart, OperatorHub/OLM, or the Strimzi Kafka CLI; namespace scoping via `STRIMZI_NAMESPACE` (single, comma-list, or empty for all-namespaces); and **load testing** Kafka deployed by Strimzi from .NET / JVM / Go / Node clients including `Hex.Scaffold` Kafka inbound (`Adapters.Inbound` consumer `BackgroundService`) and outbound (`Adapters.Outbound` producer via `Confluent.Kafka`). Triggers on phrases — "deploy strimzi", "install strimzi", "kafka on kubernetes", "kraft mode", "kafka node pool", "broker capacity", "cruise control", "kafka rebalance", "kafka quotas", "strimzi listeners", "kafka load test", "kafka perf test", "kafka throughput", "kafka p99 latency", "size kafka brokers", "tune broker network", "kafka inbound outbound", "hex-scaffold kafka", "Confluent.Kafka producer", "background service consumer". Triggers on file patterns — `**/Kafka.yaml`, `**/KafkaNodePool.yaml`, `**/KafkaTopic.yaml`, `**/KafkaUser.yaml`, `**/KafkaConnect*.yaml`, `**/KafkaMirrorMaker2.yaml`, `**/KafkaBridge.yaml`, `**/KafkaRebalance.yaml`, `**/cruise-control*.yaml`, `**/strimzi-cluster-operator*.yaml`, `helm-charts/strimzi-*/`, `addon_charts/kafka/`, `tests/loadtest/**/kafka*`, `**/values-kafka-*.yaml`. Authored by a distinguished Kubernetes Platform Engineer — emphasises **explicit role separation, per-resource capacity contracts that match what Cruise Control sees, KRaft-only minds, in-cluster low-overhead listeners during perf tests, and the saturation-band sizing methodology applied to Kafka's four limiting resources (CPU, network-in, network-out, log disk)**. Used to rank perf-test bottlenecks against PostgreSQL Platinum+ baselines already established in `hex-scaffold` and to design Kafka tier ladders that scale predictably under k6.
