> > Keep your domain name registrar, DNS service provider and application infrastructure provider separately.

> Fair point but you also get exposed if the dns provider has an outage

The usual workaround here is to put two IP addresses in your A record, one that points to your main server on hosting provider A, and the other to your mirror server on hosting provider B.

If your DNS provider goes down, cached DNS should still contain both IPs. And if one of your hosting providers goes down as well, clients should timeout and then fallback to the other IP (I believe all major browsers implement this).

Of course this is extra hassle/cost to maintain, and if you aren't quite careful in selecting hosting providers A and B, there's a good chance they have coordinated failures anyway (i.e. both have a dependency on some 3rd party like AWS/Cloudflare).