Windmill vs Cucumber-JVM comparison of testing frameworks
What are the differences between Windmill and Cucumber-JVM?

	Windmill https://pypi.org/project/windmill/	Cucumber-JVM https://github.com/cucumber/cucumber-jvm
Programming language	Python	Java
Category	UI Testing	Acceptance Testing
General info	Windmill is an Open Source Web UI testing framework for Python Windmill is an Open Source AJAX Web UI testing framework that implements in-browser recording and playback, cross browser testing and test integration	Cucumber-JVM is a pure Java implementation of Cucumber The specifications are written in plain texts, which allows them to be easily understandable by all stakeholders.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	No	No
Client-side Allows testing code execution on the client, such as a web browser	Yes Its main function is testing of front-end components and functionality	Yes You can test the front-end part like the GUI using cucumber with serenity, they integrate well to test your front-end.
Server-side Allows testing the bahovior of a server-side code	No	Yes You can test back-end components such as API's using rest&soap clients, and databases
Fixtures Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test	N/A	Yes Using the cucumber extension aruba you can create fixures in two steps: 1.Create a fixtures-directory; 2.Create fixture files in this directory
Group fixtures Allows defining a fixed, specific states of data for a group of tests (group-fixtures). This ensures specific environment for a given group of tests.	N/A	Yes You can group your fixtures inside your fixtures directories
Generators Supports data generators for tests. Data generators generate input data for test. The test is then run for each input data produced in this way.	Yes By using third party libraries	N/A
Licence Licence type governing the use and redistribution of the software	Apache License 2.0	MIT License
Mocks Mocks are objects that simulate the behavior of real objects. Using mocks allows testing some part of the code in isolation (with other parts mocked when needed)	N/A	Yes By using all of RSpec’s supported mocking frameworks (RSpec, Mocha, RR, Flexmock)
Grouping Allows organizing tests in groups	N/A	Yes Cucumber allows the use of tag Cucumber feature files or individual tests to group tests. Then, you can pass a Cucumber tagged expression at test execution that specifies the tag (grouped) tests to run. https://www.toolsqa.com/cucumber/cucumber-tags/
Other Other useful information about the testing framework