Hey so I’m pretty sure you can host your own business mail for free these days without a static IP. This is basically how it would go:
Cloudflare Tunnel installed on your box (free)
Cloudflare Email Worker connected to your domain which writes emails to a KV store (generous free tiers)
Cloudflare Worker that downloads the emails from the KV store and uses Worker TCP sockets to send it to your mail server over the tunnel via a TCP port ie 25000 (CF blocks 25)
For sending mail in blue, local mail server uses smtp2go or Azure Communication Services.
I’ve pretty much convinced that a cheap Synology rack is the best way to do this because it replaces Azure ID (Synology SSO) and Exchange (Synology Mail) which self hosted non-SaaS in the one appliance, it gets security updates, and it has a easy web interface for setting everything up.
Haven’t managed to write the Cloudflare worker code yet, but found this guys repo and he’s done pretty much all the heavy lifting: https://github.com/Sh4yy/cloudflare-email
The explicitly includes Cloudflare as one of the big services they currently used and needed to excise from their life as part of this move. Promoting consolidation from many providers to one while also switching from a generic solution to a vendor locked-in one would probably be a downgrade in their book.
I think it’s better to have all your mail data on prem. You’d only be using US companies as a transit.
Yeah there’s some lock-in with all the free Cloudflare stuff but you could probably get it running again without CF pretty fast if you needed to. If you have a static IP, skip the CF stuff!
OP suggested Proton but I’m not sure I’d want to go from one mail host to another. That’s just shifting trust and what I’m taking away from happenings of US at the moment is that being insulated from the events of the world is a good thing.
If you don't have a static IP you could just rent a cheap VPS and host your mail server there or just use it as a gateway for your home server. No need to use Cloudflare.
Cloudflare Tunnel installed on your box (free)
Cloudflare Email Worker connected to your domain which writes emails to a KV store (generous free tiers)
Cloudflare Worker that downloads the emails from the KV store and uses Worker TCP sockets to send it to your mail server over the tunnel via a TCP port ie 25000 (CF blocks 25)
For sending mail in blue, local mail server uses smtp2go or Azure Communication Services.
I’ve pretty much convinced that a cheap Synology rack is the best way to do this because it replaces Azure ID (Synology SSO) and Exchange (Synology Mail) which self hosted non-SaaS in the one appliance, it gets security updates, and it has a easy web interface for setting everything up.
Haven’t managed to write the Cloudflare worker code yet, but found this guys repo and he’s done pretty much all the heavy lifting: https://github.com/Sh4yy/cloudflare-email