MX for Hacklab's domains (edinburghhacklab.com and ehlab.uk) is handled by Al Bennett's server, mail.insertcake.com.
Messages are stored in IMAP mailboxes on the same server, or forwarded to personal accounts elsewhere.
Business email is relayed by authenticated SMTP on mail.insertcake.com.
Simon currently uses his own server for the membership alias, and this is permitted by our SPF policy.
Inbound mailing list messages are passed from mail.insertcake.com to an instance of Mailman on Tim Hawes' server, kestrel.odvik.net.
Outbound messages are split between multiple mail relays, to mitigate the risk of being blacklisted: