code&cu

Running your own mail server is easy. Getting it delivered is the hard part.

The checklist that mattered:

1. A correct PTR record (reverse DNS) matching the mail host.
2. SPF authorising the sending IP.
3. DKIM signing every outgoing message.
4. DMARC to tie it together and get reports.

Pass all four and Gmail stops sending you to the junk folder.

Cu, element 29. Copper is warm, endlessly conductive, and ages into something with character instead of just wearing out.

That felt like the right metaphor for building things on the web: low resistance, a bit of patina, and made to last.