Spek vs Buster.JS comparison of testing frameworks
What are the differences between Spek and Buster.JS?

	Spek https://www.spekframework.org/	Buster.JS https://busterjs.readthedocs.io
Programming language	Kotlin	JavaScript
Category	Acceptance Testing, Unit Testing	Unit Testing, Browser Automation
General info	Spek is a specification framework for Kotlin Spek is a Kotlin-based Specification Testing framework for the JVM. It works as a JUnit 5 Test Engine meaning that we can easily plug it into any project that already uses JUnit 5 to run alongside any other tests that we might have.	Buster.JS is a JavaScript test framework for node and browsers. Buster.JS is a new JavaScript testing framework. It does browser testing by automating test runs in actual browsers (think JsTestDriver), as well as Node.js testing. It has a bunch of great features.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	No	Yes Buster.Js is a xUnit style Test Framework
Client-side Allows testing code execution on the client, such as a web browser	Yes Yes you can test front-end behaviour by writing specifications to test front-end functionality. Developers can also write unit tests for individual front-end components.	Yes It does browser testing with browser automation, QUnit style static HTML page testing, testing in headless browsers and more front-end components and functionality
Server-side Allows testing the bahovior of a server-side code	Yes You can test back-end behaviour and componets by writing specifications to test back-end functionality and unit tests for individual back-end components	Yes It is a Node.js testing toolkit as well which means it can test back-end behaviour and functionality as well as run in a server environment
Fixtures Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test	Yes Fixtures are available in spek through functions suchas beforeEachTest() and afterEachTest()	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 spek has group fixtures available through the beforeGroup() and afterGroup() functions	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
Licence Licence type governing the use and redistribution of the software	Modified BSD License	BSD 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 You can use the third party library mockito-kotlin	Buster.JS ships with Sinon.JS. every test in a test case has a sandbox associated with it, making it easy to mock and stub
Grouping Allows organizing tests in groups	Yes Tests are written using nested lambdas, each scope (level) can either be a group or a test
Other Other useful information about the testing framework