Backend

Types package architecture for ChainGraph core definitions. THE foundation package for all development. Use when working on packages/chaingraph-types, port system, decorators, node classes, flow definitions, execution context, propagation, or any type-related code. Contains 9 port types, decorator system, compositional node architecture, execution engine. Triggers: types, port, decorator, @Node, @Input, @Output, @PortString, @PortArray, @PortObject, BaseNode, INode, IPort, IEdge, IFlow, ExecutionEngine, ExecutionContext, propagation.

Expert assistance with lenne.tech CLI for Git operations and Fullstack initialization. IMPORTANT - For ALL NestJS server development (modules, objects, properties), use the nest-server-generator skill instead, even for simple tasks. This skill handles only lt git commands and lt fullstack init.

Jira API operations via Python CLI scripts. AUTOMATICALLY TRIGGER when user mentions Jira URLs (https://jira.*/browse/*, https://*.atlassian.net/browse/*), issue keys (PROJ-123), or asks about Jira issues. Use when Claude needs to: (1) Search issues with JQL queries, (2) Get or update issue details, (3) Create new issues, (4) Transition issue status (e.g., "To Do" → "Done"), (5) Add comments, (6) Log work time (worklogs), (7) List sprints and sprint issues, (8) List boards and board issues, (9) Create or list issue links, (10) Discover available Jira fields, (11) Get user profile information, (12) Download attachments from issues. If authentication fails, offer interactive credential setup via jira-setup.py. Supports both Jira Cloud and Server/Data Center with automatic auth detection.

Core ChainGraph domain concepts - flows, nodes, ports, edges, and execution. Use for ANY ChainGraph development to understand the fundamental abstractions. Explains what flows are, how nodes process data, port types (9 types), edge data transfer, and execution lifecycle. 19 FlowEventTypes, 21 ExecutionEventEnums. Triggers: chaingraph, flow, node, port, edge, execution, what is, how does, concept, architecture, event types.

API architecture expert designing scalable, developer-friendly interfaces. Creates REST and GraphQL APIs with comprehensive documentation, focusing on consistency, performance, and developer experience.

Expert JavaScript developer specializing in modern ES2023+ features, asynchronous programming, and full-stack development. Masters both browser APIs and Node.js ecosystem with emphasis on performance and clean code patterns.

Python JSON parsing best practices covering performance optimization (orjson/msgspec), handling large files (streaming/JSONL), security (injection prevention), and advanced querying (JSONPath/JMESPath). Use when working with JSON data, parsing APIs, handling large JSON files, or optimizing JSON performance.

ChainGraph execution tRPC layer for flow execution management. Use when working on packages/chaingraph-executor or apps/chaingraph-execution-api. Covers execution lifecycle (create/start/pause/resume/stop), event streaming, DBOS workflow integration, signal pattern, API vs Worker modes. Triggers: execution procedure, subscribeToExecutionEvents, ExecutionService, chaingraph-executor, execution-api, execution workflow, DBOS signal, taskQueue, eventBus.

Senior Java architect specializing in enterprise-grade applications, Spring ecosystem, and cloud-native development. Masters modern Java features, reactive programming, and microservices patterns with focus on scalability and maintainability.

Database schema design, migrations, query optimization, and ORM patterns. Use when designing database schemas, writing migrations, optimizing queries, or working with ORMs like SQLAlchemy or Django ORM.

Expert SQL developer specializing in complex query optimization, database design, and performance tuning across PostgreSQL, MySQL, SQL Server, and Oracle. Masters advanced SQL features, indexing strategies, and data warehousing patterns.

Expert .NET Framework 4.8 specialist mastering legacy enterprise applications. Specializes in Windows-based development, Web Forms, WCF services, and Windows services with focus on maintaining and modernizing existing enterprise solutions.

Senior backend engineer specializing in scalable API development and microservices architecture. Builds robust server-side solutions with focus on performance, security, and maintainability.

Expert for Test-Driven Development (TDD) with NestJS and @lenne.tech/nest-server. Creates story tests in test/stories/, analyzes requirements, writes comprehensive tests, then uses nest-server-generator skill to implement features until all tests pass. Ensures high code quality and security compliance. Use in projects with @lenne.tech/nest-server in package.json dependencies (supports monorepos with projects/*, packages/*, apps/* structure).

Expert C# developer specializing in modern .NET development, ASP.NET Core, and cloud-native applications. Masters C# 12 features, Blazor, and cross-platform development with emphasis on performance and clean architecture.

Expert Go developer specializing in high-performance systems, concurrent programming, and cloud-native microservices. Masters idiomatic Go patterns with emphasis on simplicity, efficiency, and reliability.

Use when user asks to search the web, look something up online, find current/recent/latest information, or needs cited answers. Triggers on "search", "look up", "find out about", "what is the current/latest", image searches, news lookups. NOT for searching code/files—only for web/internet searches.

Analyze AppWorld task failures to extract specific API patterns and generate actionable playbook bullets with concrete code examples

PRIMARY expert for ALL NestJS and @lenne.tech/nest-server tasks. ALWAYS use this skill when working in projects with @lenne.tech/nest-server in package.json dependencies (supports monorepos with projects/*, packages/*, apps/* structure), or when asked about NestJS modules, services, controllers, resolvers, models, objects, tests, server creation, debugging, or any NestJS/nest-server development task. Handles lt server commands, security analysis, test creation, and all backend development. ALWAYS reads CrudService base class before working with Services.

Use when needing to scrape documentation websites into markdown for AI context. Triggers on "scrape docs", "download documentation", "get docs for [library]", or creating local copies of online documentation. CRITICAL - always analyze sitemap first before scraping.