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Specula is an agentic system that automates the process of software bug finding through authoring and model-checking a spec for the code. It derives TLA+ specifications automatically from the code, checks code-spec conformance through trace validation, model checks the spec to find concurrency bugs, and reproduces the bug at the code layer by writing integration tests with precise timing. I remember reading the Daikon paper "Quickly detecting relevant program invariants" in 2000 and getting impressed by it, and here we are after 26 years, solving the end-to-end problem much better than I ever thought would be possible in a push-button manner in the year of our lord 2026. But somehow, I am still somewhat unsatisfied with the paper. This may be me being hypercritical and trying to get more out of the paper by arguing with it . So bare with me until I resolve (or learn to accept) these problems over time. I know many of the authors of the Specula work, and respect them, and I...

This week, I presented this paper at ICCCN'26. This is joint work with Aleksey Charapko (University of New Hampshire) and my MongoDB colleagues Matt Broadstone, Daniel Gomez Ferro, and Akshat Vig. The paper investigates how to build a metastability tolerant execution control system (ECS) for a database. Why? Modern databases are complex networked systems serving mixed workloads: short queries (that want an answer in milliseconds) sitting next to analytics jobs (that want the CPU for multiple seconds). The arrival rate of requests is effectively unbounded, but of course, the server's resources are not. And, unfortunately, elastic scaling does not save you here. Scaling takes minutes, whereas, overload takes seconds. Admission control tries to guard the front door (more on this later), but the component that mediates contention once requests reach the backend is the execution control system (ECS). Unlike a closed system OS scheduler, which strives for fairness and completeness b...