[dave78]

> I don't see mention of open source alternatives

Check out Nebula (created by Slack) - https://github.com/slackhq/nebula

Fundamentally very similar to Tailscale. I've been using it for years and it has been flawless. It doesn't have as many bells and whistles as Tailscale but it does what it does very well.

[stock_toaster]

I use nebula too. Originally manually, but more recently with defined.net (hosted admin interface). Nebula works great!