Sobo: Zed's testing infrastructure is fully deterministic and simulates network scheduling
Nathan Sobo · Zed Agents — with Zed Cofounders Nathan Sobo & Antonio Scandurra · May 7, 2025 · at 14:14
Nathan Sobo details Zed's engineering methodology and testing architecture prior to incorporating non-deterministic LLMs.
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“Like one of the cool things about the way we've done testing and thus far in Zed is everything is fully deterministic. We even simulate like network interaction and we literally simulate the scheduler such that we can interleave deterministically network messages. Everything's determined, deterministically tested and rant fuzz tested.”
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