WebdriverIO vs Wallaby.js comparison of testing frameworks
What are the differences between WebdriverIO and Wallaby.js?

	WebdriverIO https://webdriver.io/	Wallaby.js https://wallabyjs.com/
Programming language	JavaScript	JavaScript
Category	Browser Automation, Unit Testing, Functional Testing	Unit Testing
General info	WebdriverIO is the next-gen WebDriver test framework for Node.js made upon Selenium WebdriverIO is written in JavaScript and uses Selenium under the hood. It also comes with its own inbuilt test runner and supports other testing frameworks like Jasmine, Cucumber, and Mocha	Wallaby.js is an integrated continuous testing tool for JavaScript. Wallaby.js runs your tests immediately as you change your code (you don’t even have to save the file) and reports code coverage and other results directly to your code editor. Its also uses various techniques such as dependency analysis to only execute tests affected by your code changes and parallel test execution to ensure your tests run as fast as possible.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	Yes	N/A
Client-side Allows testing code execution on the client, such as a web browser	Yes WebdriverIO allows the use of advanced CSS selectors and makes it easy to find elements for front-end testing	Yes Wallaby.js can test front-end components and functionality
Server-side Allows testing the bahovior of a server-side code	Yes It can be used to test server side behaviour and functionality	Yes Wallaby.js can test server behaviour and functionality
Fixtures Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test	Yes WebdriverIO supports the creation of fixtures	N/A
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.	Yes WebdriverIO supports the creation of group fixtures	N/A
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.	N/A	N/A
Licence Licence type governing the use and redistribution of the software	MIT License	N/A
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)	Yes It contains a mocking service called 'wdio-wiremock-service'	By use of a third party library Jest works well with wallaby
Grouping Allows organizing tests in groups	Yes WebdriverIO allows one to build test suites, you can run these test in parallel and organize them by adjusting the 'maxInstances' property in your config file
Other Other useful information about the testing framework