tl;dr It’s a distributed hosting / storage platform on top of an overlay networks, being developed by one company. Apparently not based on DAT or IPFS or any blockchain. Everything’s GPLv3 licensed except for the network library which both MIT and modified BSD. There’s some kind of payment scheme to incentivize hosts, al la Storj (and others). I’d love to see a third-party audit.
Lots of claims being made in verbose style, not much technical info at the linked site. Try https://hub.safedev.org/core_technology