Best Self Hosted Alternatives to Backstage

EventCatalog is an open source documentation tool that helps teams model and document distributed software architecture. It focuses on making domains, services, events, schemas, and their relationships discoverable and searchable across event-driven and microservice systems.

Key Features

• Markdown- and MDX-driven content for documenting domains, services, messages/events, and schemas
• Generation and synchronization of catalog content from OpenAPI and AsyncAPI inputs
• Schema and architecture primitives designed to capture ownership, dependencies, and relationships
• Diagram support (including versioned diagrams stored with your repository) to document system views and flows
• CLI-driven workflows suitable for local use and CI/CD automation
• Extensible via SDK/API to integrate with custom brokers, registries, or internal systems
• AI-oriented capabilities such as querying structured architecture knowledge and MCP server integration

Use Cases

• Create a searchable source of truth for event-driven architectures across teams and repositories
• Keep architecture documentation aligned with API/spec changes by regenerating catalog content in CI/CD
• Improve onboarding and incident response by making owners, dependencies, and event flows easy to discover

EventCatalog works well for organizations adopting DDD, microservices, and event-driven architecture who want documentation to evolve with their system rather than drift over time. It is especially useful when architecture knowledge is fragmented across multiple tools and teams.