~/blog

• Bounce codes that look like a content problem

  A 5.7.1 that mentions content often shares that code with reputation, authentication, and tenant rules, and the sentence is a weak guide to which one fired.

• Complaint loops that teach filters the wrong lesson

  Spam marks are labeled training data for mailbox filters. Delayed suppressions and weak consent keep teaching the wrong lesson.

• Why mailbox warm-up is not a substitute for list hygiene

  Warm-up teaches receivers about a new sending identity. It cannot rescue a list full of stale addresses, traps, and unearned consent.

• The order to fix SPF, DKIM, and DMARC when placement falls

  When inbox placement slips, repair authentication in a sequence that keeps your own mail safe: confirm the failure, fix DKIM, rebuild SPF, then tighten DMARC.

• When a shared sending IP looks fine until one neighbor burns it

  Shared pools can look healthy in your own metrics while a neighboring sender wrecks the IP reputation that receivers actually score.

• Why your outbound is dragging down your transactional stream

  A guest post from the Mailapult team on why outbound sales programs and transactional email need to be separated, and how the separation is implemented in practice.

• What deliverability actually depends on

  A practitioner view of what moves inbox placement, what does not, and how to invest the limited attention an in-house team can spare on the topic.

• When to outsource your email infrastructure

  A practical decision framework for product and ops teams trying to decide whether to keep running their own email stack or hand it to a team that does this for a living.