Corsair: Run Your Own Mail Server

Why it surfaced

Corsair explains the whole mail stack with unusual specificity, from SPF, DKIM, and DMARC processing to signed webhooks and DNS record management. Its documentation also admits the unglamorous prerequisites—static IPs, PTR records, open port 25—and offers a laptop-safe setup where mail never leaves the machine.

An open-source, self-hosted email server that combines SMTP, IMAP, POP3, JMAP, webmail, filtering, and a control panel in one Bun process.