Use when a sanitized issue summary, requirement summary, or design brief needs technical design exploration before creating ADRs, specifications, or implementation plans. This skill inspects repository context, clarifies material ambiguity, compares feasible approaches and trade-offs, recommends a direction, obtains approval, and identifies ADR candidates. This should trigger for requests such as Explore a design; Compare implementation approaches; Recommend an architecture direction; Clarify technical options before planning. Part of cursor-rules-java project

Use when you need to design, review, or improve modular monoliths with Spring Modulith in Spring Boot applications - including application module package structure, ApplicationModules verification, named interfaces, allowed dependencies, domain events, @ApplicationModuleTest, Scenario-based module tests, generated documentation, actuator exposure, observability, and event publication registry choices. This should trigger for requests such as Add Spring Modulith to a Spring Boot application; Review Spring Modulith module boundaries; Improve modular monolith architecture in Spring Boot; Add @ApplicationModuleTest tests; Generate Spring Modulith documentation. Part of cursor-rules-java project

Use when building or reviewing core Quarkus applications with CDI beans and scopes, SmallRye Config and profiles, lifecycle, interceptors and events, virtual threads, and test-friendly design. This should trigger for requests such as Review Java code for Quarkus application structure and CDI; Apply best practices for Quarkus configuration and beans; Improve CDI interceptors, events, or programmatic injection in Quarkus; Add virtual-thread configuration or tune CDI lifecycle. Part of cursor-rules-java project

Use when reviewing, designing, or modifying Java enterprise systems that may support financial entities, critical ICT services, third-party ICT provider integrations, or operational resilience obligations under DORA. This should trigger for requests such as Review a Java platform for DORA ICT risk controls; Design operational resilience evidence for a financial service; Add incident, continuity, backup, recovery, or third-party ICT controls; Assess resilience testing and monitoring before production release. Part of cursor-rules-java project

Use when reviewing, designing, or modifying Java enterprise systems that may support essential or important entities, critical-sector services, managed service providers, supply-chain dependencies, or cybersecurity incident escalation obligations under NIS2. This should trigger for requests such as Review a Java platform for NIS2 cybersecurity controls; Design operational evidence for critical-sector services; Add incident detection, escalation, continuity, or supply-chain security controls; Assess cybersecurity risk management before production release. Part of cursor-rules-java project

Use when reviewing, designing, or modifying Java enterprise systems that expose, exchange, store, process, export, or port data across users, businesses, connected products, cloud providers, APIs, event streams, AI data pipelines, data spaces, or SaaS platforms and need EU Data Act engineering controls. This should trigger for requests such as Review a Java platform for EU Data Act controls; Design data access and portability evidence; Add data-sharing request workflows, export formats, interoperability, metadata, audit logs, cloud-switching support, non-personal data safeguards, or trade-secret handoffs; Assess Data Act engineering readiness before production release. Part of cursor-rules-java project

Use when reviewing, designing, or modifying Java enterprise systems that may support intermediary services, hosting services, online platforms, marketplaces, content moderation, recommender systems, advertising delivery, complaint workflows, transparency reporting, or systemic-risk evidence under the EU Digital Services Act. This should trigger for requests such as Review a Java online platform for DSA controls; Design notice-and-action or appeal workflows; Add recommender, ad transparency, moderation, audit, researcher access, or privacy-safe observability evidence; Assess online-platform transparency controls before production release. Part of cursor-rules-java project

Generate a comprehensive AGENTS.md file for Java repositories through a modular, step-based interactive process that covers role definition, tech stack, file structure, commands, Git workflow, and contributor boundaries. **This is an interactive SKILL**.

Implement effective Java metrics instrumentation with Micrometer by defining meaningful service-level metrics, controlling cardinality, selecting the right meter type, and exposing production-ready telemetry for dashboards and alerting.

Identify and apply practical Java high-performance techniques using a measure-first approach, with emphasis on allocation reduction, data layout, concurrency discipline, and evidence-based validation.

Prove real wiring in Micronaut with containers and HTTP.

Apply REST design principles for Micronaut HTTP applications.

Apply fast testing strategies for Micronaut: Mockito-first, narrow @MicronautTest when HTTP or DI replacement is required.

Help teams design maintainable, secure, and performant **MongoDB and non-relational database queries** for Java applications.

Apply Quarkus Kafka guidance with concrete examples for design, implementation, and error handling.

Apply programmatic JDBC patterns in Quarkus with safe SQL and clear transactions.

Apply REST API design principles on Quarkus using Jakarta REST (JAX-RS).

Apply fast testing strategies for Quarkus: Mockito-first, QuarkusTest when CDI wiring matters.

Apply Quarkus validation best practices at REST boundaries.

Provide a complete Gatling performance testing setup for Java Maven projects by adding the required test dependencies and Gatling Maven plugin configuration, creating or guiding Java simulation placement, and explaining how to run simulations and inspect reports.