Reproducing rare bugs found during fuzz testing is hard because software can run slightly differently every time. Bedrock is a hypervisor that controls that randomness, so given the same inputs a program runs identically on every execution.
Niklas outlines an approach and a solution, bedrock, for this problem of determinism. He focuses on the challenge of emulating time and pausing a VM at an exact instruction count, something CPUs aren't designed to do.
https://brink.dev/blog/2026/06/25/bedrock-deterministic-hypervisor/
The result is an open source tool, bedrock: an experimental hypervisor purpose-built for deterministic software testing.
https://github.com/oss-garage/bedrock
schmidty
npub1zs…kk4em
2026-06-25 14:07:53 UTC
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wss://relay.primal.netPublished at
2026-06-25 14:07:53 UTCEvent JSON
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"content": "Reproducing rare bugs found during fuzz testing is hard because software can run slightly differently every time. Bedrock is a hypervisor that controls that randomness, so given the same inputs a program runs identically on every execution.\n\nNiklas outlines an approach and a solution, bedrock, for this problem of determinism. He focuses on the challenge of emulating time and pausing a VM at an exact instruction count, something CPUs aren't designed to do.\nhttps://brink.dev/blog/2026/06/25/bedrock-deterministic-hypervisor/\n\nThe result is an open source tool, bedrock: an experimental hypervisor purpose-built for deterministic software testing.\nhttps://github.com/oss-garage/bedrock",
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