MiniZinc - MiniZinc is a free and open-source constraint modeling language.
Kissflow - Kissflow is a workflow tool & business process workflow management software to automate your workflow process. Rated #1 cloud workflow software in Google Apps Marketplace.
OptaPlanner - Mathematical optimization software
ProntoForms - ProntoForms is a mobile business solutions application, converting paper forms onto any tablet or mobile device.
Drools - Drools introduces the Business Logic integration Platform which provides a unified and integrated platform for Rules, Workflow and Event Processing.
Nintex - Cloud-based digital workflow management automation platform