Tools
Small, focused tools for running email infrastructure.
Classifies SMTP rejections and deferrals into a category and an action. Hard and soft bounce is too coarse to act on: a full mailbox, a rate limit and a reputation block all arrive as soft bounces and need opposite responses.
github.com/singhrastu/smtpsift
Audits a domain's email authentication posture: SPF including the 10-lookup limit, DKIM, DMARC policy strength, MTA-STS policy and MX consistency, TLS-RPT and BIMI, with a composite verdict against the Gmail, Yahoo and Microsoft bulk sender requirements.