The Cassowary constraint solver
# Cassowary A Smalltalk Cassowary constraint solver, ported from the original... https://constraints.cs.washington.edu/cassowary/ Cassowary is an incremental constraint solving toolkit that efficiently solves systems of linear equalities and inequalities. Constraints may be either requirements or preferences. Client code specifies the constraints to be maintained, and the solver updates the constrained variables to have values that satisfy the constraints. A technical report is included in "docs" folder that describes the algorithm, interface, and implementation of the Cassowary solver.