According to their pricing page, > ZeroTier’s software is open source and free to use for most purposes including personal use, internal use within a business

According to their pricing page, > ZeroTier’s software is open source and free to use for most purposes including personal use, internal use within a business or academic institution, and evaluation for uses that require commercial licensing. I was able to find this: https://github.com/zerotier/ZeroTierOne https://github.com/zerotier/ZeroTierOne