I have been looking for a self managed, preferably open source, backup tool that could mirror the contents of my MacBook hard drive to a local NAS running Linux. My current solution involves BTSync 1.4, but I do not like this solution because it's no longer supported, and BTSync 2 is a mass, as far as I am concerned, and I do not like the direction it's going in. Basically I want to pick some directories on my laptop and have them constantly sync to a location on my NAS, when ever the NAS is accessible. One way sync would be just fine, as it's for backup only, and no versioning is necessary, as I can implement that on the NAS separately.
Rsync is a fine solution, but I would prefer something with file tree monitoring, so changes could be propagated immediately. Any ideas? I looked into crashplan, but again, it's a closed source solution that requires creating an account, and I would prefer my backup solution to be "Zombi Apocalypse" ready :)
Mac and Linux only solution would be fine, but something that supports windows would be nice too.