Structurizr
Implements the C4 model as a diagrams-as-code DSL — write Structurizr DSL and render multiple architecture views (Context, Container, Component, Code) from a single model. Version-controlled alongside code with full ADR integration. Free OSS CLI plus paid cloud workspace for team collaboration.
Eraser
Generate architecture diagrams, ERDs, cloud infrastructure diagrams, and sequence diagrams from natural language or code via DiagramGPT. Supports GitHub sync and a VS Code extension so diagrams stay connected to code. SOC II Type 2 compliant and never trains on user data.