What is the 9-step event modeling workflow?

It is a structured methodology for discovering domain actors, brainstorming events, mapping commands, and designing the read models and automations required for a complete event-sourced system.

Does this skill write application code?

No, this skill focuses strictly on the design and modeling phase. It produces documentation and architectural blueprints that serve as the ground truth for downstream implementation.

What are vertical slices in this context?

Vertical slices are independent units of functionality—such as state changes, views, or automations—that include all necessary layers from infrastructure to presentation.

How does it handle model validation?

It validates the model by ensuring every read model field traces back to an event and every command has documented business rules, preventing information gaps before coding starts.

Event Modeling Facilitator

Name: Event Modeling Facilitator
Author: jwilger

byjwilger

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Collaboration Tools

Facilitates structured event modeling sessions to design robust event-sourced systems using a 9-step discovery and design workflow.

This skill empowers Claude to act as a domain modeling expert, guiding teams through Martin Dilger's 'Understanding Eventsourcing' methodology. It bridges the gap between business requirements and technical implementation by surfacing hidden domain knowledge through a structured conversation. By focusing on immutable events and vertical slices before any code is written, it ensures that the resulting architecture is both business-aligned and technically sound, producing complete documentation including actors, commands, read models, and Given/When/Then acceptance criteria.

Key Features

01Standardized documentation output for domain overviews and workflow maps.

022 GitHub stars

03Formal Given/When/Then (GWT) scenario authoring for business rule validation.

04Guided 9-step event modeling workflow for domain discovery and system design.

05Automated model validation to ensure data traceability and logical completeness.

06Automatic generation of immutable event-sourced architectures and vertical slices.

Use Cases

01Designing a new event-driven microservice from scratch with shared domain understanding.

02Decomposing complex business workflows into independent, testable vertical slices.

03Refining system requirements into formal acceptance criteria using Given/When/Then syntax.

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add jwilger/agent-skills event-modeling

For use in Claude.ai and ChatGPT

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