API references (Sandbox): https://sandbox.penneo.com/api/docs
Documentation: https://penneo.readme.io/
.NET SDK: https://github.com/Penneo/sdk-net
PHP SDK: https://github.com/Penneo/sdk-php
Javascript SDK: https://github.com/Penneo/sdk-js
Crash guide can be found here: https://penneo.zendesk.com/hc/da/articles/115001130563