Writing

Notes on developer tooling, supply-chain security, and whatever I've been measuring lately.

Your model transferred. Your alerts didn't.

A sepsis model crossed from medical ICU to surgical ICU with its AUROC almost intact and lost 91% of its clinical value. Discrimination and the operating point fail independently, and the one number everyone reports is insensitive to the failure that costs the most.

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Five results that did not replicate

I spent a week measuring a biomedical knowledge graph system. Five separate results looked solid at a single configuration and dissolved under a second one. Here is each mechanism, and the one that nearly shipped as a feature.

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What's actually in the top 100 Rust crates

I scanned the 100 most-downloaded crates on crates.io for capability surface: unsafe, FFI, process spawning, network access, build scripts. 73% of everything comes from two crates, and most of the alarming numbers are test code.

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