A curated list of awesome open source workflow engines

• Airflow - Python-based platform for running directed acyclic graphs (DAGs) of tasks
• Argo - Open source container-native workflow engine for getting work done on Kubernetes
• Azkaban - Batch workflow job scheduler created at LinkedIn to run Hadoop jobs.
• Cadence - An orchestration engine to execute asynchronous long-running business logic developed by Uber Engineering.
• CloudSlang - Workflow engine to automate your DevOps use cases.
• Conductor - Netflix's Conductor is an orchestration engine that runs in the cloud.
• DigDag - Digdag is a simple tool that helps you to build, run, schedule, and monitor complex pipelines of tasks.
• Fission Workflows - A high-perfomant workflow engine for serverless functions on Kubernetes.
• Flor - A workflow engine written in Ruby.
• Imixs-Workflow - A powerful human-centric Workflow Engine based on the BPMN 2.0 standard.
• Kiba - Data processing & ETL framework for Ruby
• Mistral - Workflow service, in OpenStack foundation.
• Oozie - Workflow Scheduler for Hadoop.
• Piper - A distributed Java workflow engine designed to be dead simple.
• Pinball - scalable workflow manager by Pinterest
• RunDeck - Job Scheduler and Runbook Automation.
• Wexflow - A high-performance, extensible, modular and cross-platform workflow engine.
• Workflow Engine - A lightweight .NET and Java workflow engine.
• Workflow Core - Workflow Core is a light weight workflow engine targeting .NET Standard.
• Copper - A high performance Java workflow engine.
• Zeebe - A workflow engine for microservices orchestration that's capable of executing BPMN models, developed by the team at Camunda

• jBPM - The core of jBPM is a light-weight, extensible workflow engine written in pure Java that allows you to execute business processes using the latest BPMN 2.0 specification.
• Activiti - Activiti is a leading lightweight, java-centric open-source BPMN engine supporting real-world process automation needs.
• Activiti Cloud is now the new generation of business automation platform offering a set of cloud native building blocks designed to run on distributed infrastructures.
• Flowable - The Flowable project provides a core set of open source business process engines that are compact and highly efficient. They provide a workflow and Business Process Management (BPM) platform for developers, system admins and business users.

• Bip.io - Web Automation For People And Robots.

• Luigi - Python module that helps you build complex pipelines of batch jobs.
• Camunda - Both a java library and optionally a full fledged product on top of it.
• Captain - Distributed, light-weight java workflow engine for a microservice architecture.
• Viewflow - Reusable workflow library that helps organize people collaboration business logic in django applications.
• Workflow Core - Lightweight workflow engine for .NET Standard