From a quick search, it seems you can use `services.postfix.config` and pass key-value pairs as arbitrary options. Not familiar with this service, but usually if a given one has more complex syntax, there is a “pass-through” option that will simply append to the given config file whatever text you provide, as well as as the sister reply says you can create manually additional files.
The thing with a lot of server software (like postfix) is that configuration is usually spread across many files.
And then there is the re-use of things between services, for example DKIM’s generated public key should be made available as a TXT record by the DNS server, the SSL certificate kept up-to-date by the web server should be used by both the smtp and imap servers, though it may need to include the full chain, and services may need to be relaunched, if the certificate is updated, etc.
I was hoping to hear from someone who had managed to get a “full” server running (with SMTP, IMAP, DKIM, DNS, DNSSec, HTTPS via ACME, etc.), because while I know that I can output raw configuration files, it seems like an extremely daunting task to weave all this together in something semantically meaningful.
Right now I have /etc under git control and a Makefile that handles all dependencies between the various pieces (i.e. to ensure proper files are regenerated/indexed as needed, and services relaunched when dependencies are updated).
Even better: `man configuration.nix` and `man home-configuration.nix`. I used the website first, but found out just using the quite good man pages is much much faster.
From a quick search, it seems you can use `services.postfix.config` and pass key-value pairs as arbitrary options. Not familiar with this service, but usually if a given one has more complex syntax, there is a “pass-through” option that will simply append to the given config file whatever text you provide, as well as as the sister reply says you can create manually additional files.