I’ve been building a 'Flight Simulator' for AI Engineers to practice fixing production failures (like RAG hallucinations, context window overflows, and rate limit storms).
The hardest part was building the execution engine to run untrusted user code securely. I realized this infrastructure is useful on its own, so I open-sourced the core engine today.
The Stack:
Orchestrator: Next.js 15 (App Router)
Isolation: Firecracker MicroVMs (via E2B)
Streaming: Real-time stdout/stderr piping via Server-Sent Events
You can try the live challenges (fixing a ReDoS attack or a 'Hanging Stream') here: https://tentropy.co/
I’ve been building a 'Flight Simulator' for AI Engineers to practice fixing production failures (like RAG hallucinations, context window overflows, and rate limit storms).
The hardest part was building the execution engine to run untrusted user code securely. I realized this infrastructure is useful on its own, so I open-sourced the core engine today.
The Stack:
Orchestrator: Next.js 15 (App Router)
Isolation: Firecracker MicroVMs (via E2B)
Streaming: Real-time stdout/stderr piping via Server-Sent Events
You can try the live challenges (fixing a ReDoS attack or a 'Hanging Stream') here: https://tentropy.co/
Or check out the core engine source here: https://github.com/jaliil-9/tentropy-core
Feedback on the sandboxing approach is welcome!