Investigate QuickJS as an asyncio-friendly JS sandbox#107
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Builds AsyncQuickJSSandbox with memory + wall-clock limits, exposing selected Python functions (including async httpx-backed fetch) to sandboxed JavaScript. Documents three important gotchas: time-limit is incompatible with Python callbacks, it cannot be used to interrupt from another thread, and raising Python exceptions in callbacks corrupts the context. https://claude.ai/code/session_01NcLEygpripiZZYRLPAP4UY
test_kill_thread.py confirms pure-JS infinite loops can't be killed in-process: ctypes exception injection only fires on Python bytecode, and QuickJS runs entirely in C. sandbox_process.py forks a child, forwards fetch/sleep RPCs to the parent's asyncio loop, and SIGKILLs the child on timeout. Costs ~15ms of fork overhead per run but guarantees termination of adversarial JS. https://claude.ai/code/session_01NcLEygpripiZZYRLPAP4UY
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Builds AsyncQuickJSSandbox with memory + wall-clock limits, exposing
selected Python functions (including async httpx-backed fetch) to
sandboxed JavaScript. Documents three important gotchas: time-limit is
incompatible with Python callbacks, it cannot be used to interrupt from
another thread, and raising Python exceptions in callbacks corrupts the
context.
https://claude.ai/code/session_01NcLEygpripiZZYRLPAP4UY