Not him, but I'm gonna use this as a chance to plug unison[1]. I've been using it for more than a year now to keep files synced across more than 3 computers and it works flawlessly. It gets a tad slow to start propogating changes if you have too many files and a weak server (around 150k files, server has an Atom N2800), but it's not more than 15 seconds.

One nifty thing is that you don't need to run unison on the server ever, just have it installed. I have systemd units that I enable on my client machines and that does all of the syncing; unison connects to the server with ssh and does all the work there over that.

[1]: https://www.cis.upenn.edu/~bcpierce/unison/index.html