Pritunl Zero was originally released as a subscription only service to provide zero trust security for SSH and web applications. Today a free version has been released with all features excluding single sign-on. Below are links to getting started tutorials for Pritunl Zero.
Getting Started with SSH Certificates
Getting Started with Internal Web Services
Gitlab Web and SSH Tutorial
Free Alternative to CloudFlare, ScaleFT and Teleport
The free version of Pritunl Zero has most of the features and in many cases more features then CloudFlare Access, ScaleFT and Gravitational Teleport.
Pritunl Cloud Development Beta
Pritunl Cloud is a new private cloud product that is currently in development. A free development beta is available for testing.