Developer builds system-design lab that validates architecture against real Docker infra

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A developer has created Torollo, a local system-design lab that backs visual architecture diagrams with real Docker containers and networks on the user's machine. Unlike traditional diagram tools, Torollo's validator checks the actual running environment rather than the appearance of the diagram. For example, if an exercise requires PostgreSQL to be isolated from a load balancer, the tool tests the real network connection and fails the step if the port remains accessible. The project uses React, React Flow, and TypeScript on the frontend, with a Node.js and Dockerode backend maintaining a strict separation between what the canvas depicts and what can be observed at runtime. The developer also built a diagnostic CLI command to help users identify environment-specific issues, such as limitations in rootless Docker setups that affect advanced networking behavior.

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