MiniZinc is a medium-level constraint modelling language. It is high-level enough to express most constraint problems easily, but low-level enough that it can be mapped onto existing solvers easily and consistently. It is a subset of the higher-level language Zinc.
MiniZinc can target a large range of target solvers, which accept their own variant of the FlatZinc modelling language.
MiniZinc can be downloaded from the MiniZinc website.
All the MiniZinc models can be downloaded as a zip file