@blueberry do you have some interest in linear programming? i keep stumbling over it for graphical models to yield MAP solutions. i have found https://github.com/quantego/clp-java which seems to be the fastest open-source solver
there are gurobi and cplex ofc. which people here at university also use
There is also a jsr https://cpstandard.wordpress.com/2016/08/16/jsr-331-update/, so this should cut it
https://cpstandard.wordpress.com/2013/04/30/clojure-and-jsr-331/
yes generally, but not at the moment
ok