Just be aware that implementing a multithreaded constraint solver is something that you will have to spend a lot of time on.
Btw, Apple is using a version of Cassowary. There are many implementations available:
http://overconstrained.io/
Ola Fosheim Grøstad via Digitalmars-d-announce Tue, 28 May 2019 01:21:02 -0700
Just be aware that implementing a multithreaded constraint solver is something that you will have to spend a lot of time on.
Btw, Apple is using a version of Cassowary. There are many implementations available:
http://overconstrained.io/