Free node based Workflow Automation Tool. Easily automate tasks accross different services.
StackStorm (aka "IFTTT for Ops") is event-driven automation for auto-remediation, security responses, troubleshooting, deployments, and more. Includes rules engine, workflow, 160 integration packs with 6000+ actions (see https://exchange.stackstorm.org) and ChatOps. Installer at https://docs.stackstorm.com/install/index.html. Questions? https://forum.stackstorm.com/.
Activiti is a light-weight workflow and Business Process Management (BPM) Platform targeted at business people, developers and system admins. Its core is a super-fast and rock-solid BPMN 2 process engine for Java. It's open-source and distributed under the Apache license. Activiti runs in any Java application, on a server, on a cluster or in the cloud. It integrates perfectly with Spring, it is extremely lightweight and based on simple concepts.