Javascript jasmine node.js and Alexa

Resources
Alexa
User Account Linking in Alexa with ASP.NET Web API (Heather Downing, Okta)

Linking Your Alexa Skill Securely with Okta (Jefferson Haw, Okta)

Account Linking : Amazon Alexa and ForgeRock OpenAM using OAuth2 Authorization grant (karthik, Medium)

How to set up Account Linking for Alexa with Auth0 and Jovo (Kaan Kilic, Jovo) and Build an Alexa Skill in Node.js with Jovo (Jan Konig, Jovo)

Interaction-Based Authentication for Alexa Skills with Auth0 (Joao Angelo, Auth0)

JavaScript
Node.js based testing (npm test)

jasmine official website

commonly used commands:
npm install –save-dev jasmine
npm init
npm test

Sample project can be seen here: (please contact me if the repository is private)

Also
Learn JavaScript in 2019 (David Neal)