eigenslur — notes by azide

Categorical Probability

Probability Maps as First-Class Arrows

Treat probability maps as composable arrows with Wasserstein distance built in — clean plumbing for stochastic systems and robust belief comparison.

Topos-Theoretic Probability

Descent as Epistemic Coherence

Treat uncertainty not as noise on one global picture, but as local beliefs that must agree where they overlap. Bayesian updating becomes 'make the locals compatible, then glue.'

Seams and Signals

A voltmeter that loops back to a different reading. Three rankings that disagree in a cycle. A warehouse whose aisles all reconcile and whose total still comes up short. The gap they share has a name, a 1931 thesis behind it, and a mesh you can poke at.

Muster: Making Little Linux Services Less Haunted

A repo scaffold you hand to Codex, Claude Code, or any coding agent so the small Linux service you built this weekend is still installable, updateable, and rollback-safe in six months. Includes a worked reference — dvd-ingester — and a pattern library of reusable solution atoms.

Engineering the Compatible Overlap

Five patterns that make a third place actually glue, anchored in Martine Postma's Repair Café, Cynthia Dwork's differential privacy, and a concrete St. Louis design — how to add 1-cochains to your city without surveilling anyone.

The Bridgehead Index

A spreadsheet method for finding the people who quietly hold a room together — and the bridges that break if they stop showing up. From Paul Erdős in Warsaw to Ronald Burt's 673 supply-chain managers to a worked example you can run before lunch.