API: https://github.com/inshopgroup/inshop-crm-api
Client: https://github.com/inshopgroup/inshop-crm-client
Demo: https://demo.inshopcrm.com/signin
It can be used as a standalone product, or as a core for new projects. CRM has a lot of functionality, like JWT authorization, user management and roles restrictions and many others.
We'll be happy to answer any questions and discuss new functionality.