For a long time, I have written structured mathematical derivations by hand and then transcribed them into a more durable form.

The calculations collected here are mostly concerned with relation algebra, predicate calculus, Galois connections, and calculational proof. They are not always essays. Often they are closer to a working archive: parameters, assumptions, definitions, observations, and proofs arranged so that the dependencies are visible.

The main archive lives in derivary.

This blog is a place for occasional commentary on that archive: why a calculation matters, how results connect, and what I am trying to understand.

For now, this is just a small first post. A way to test the water.