WebdriverIO vs Sleipnir comparison of testing frameworks
What are the differences between WebdriverIO and Sleipnir?

	WebdriverIO https://webdriver.io/	Sleipnir https://github.com/railsware/Sleipnir
Programming language	JavaScript	Swift
Category	Browser Automation, Unit Testing, Functional Testing	Unit Testing, Acceptance 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	Sleipnir is a BDD-style framework for Swift Sleipnir is a pure Swift BDD testing framework inspired by cedar, that is not dependent on NSObject, and does not use XCTest. Sleipnir has nice command line output and support for custom test reporters and other features, like seeded random tests invocation, focused and excluded examples/groups
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 You can test front-end behaviour by defining specifications for classes, objects and functions
Server-side Allows testing the bahovior of a server-side code	Yes It can be used to test server side behaviour and functionality	Yes You can test back-end behaviour by defining specifications for classes, objects and functions in the back-end
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	Yes Fixtures are available by using beforeEach{ } and afterEach{ } to setup the test parameters
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	Yes Group fixtures are available through the beforeAll{} and afterAll{} blocks to setup group fixtures
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	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)	Yes It contains a mocking service called 'wdio-wiremock-service'	Yes Yes, developers can create mock objects with sleipnir using a third party library like Cuckoo.
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	Yes You can declare example groups with Slepnir
Other Other useful information about the testing framework