The "DIY" solution is mentioned in the article. Buy a bunch of standard WAPs (the Ubiquiti UniFi range is popular) and wire them together with ethernet.
The Ubiquiti APs (e.g., the AC-PRO) can uplink to each other wirelessly, but only through one hop.
Also, you're giving up half your antenna-seconds for that. I tried it and was not happy—the hardwired performance is generally great, though.
If you 1) don't have ethernet throughout the house, 2) don't have satellite internet, and 3) can spend a little more, I recommend a pair or more of MoCA adapters as backhaul for the APs. You'll likely get better performance than mesh networking.