MailSlurp resources
Email API, deliverability, and QA engineering blog - Page 12
Tactical writing for teams building reliable email and SMS workflows in development, CI, and production operations.
Posts
Plus Addressing for Customer-Level Email Routing
Implement email plus addressing to route customer replies and inbound messages into deterministic webhooks, queues, and support workflows.
Read more technicalNodemailer NPM Guide: Send Email with Node.js SMTP
Learn Nodemailer SMTP setup for Node.js, secure credential handling, common failure fixes, and CI-ready send-and-receive email testing workflows.
Read more technicalNBSP Meaning in HTML Emails and Why It Matters
Learn the nbsp meaning, how the non-breaking space character works in HTML emails, and when to use it safely in templates.
Read more technicalMailinator Alternatives: Private Inboxes, APIs, and CI Testing
Compare Mailinator alternatives for private inbox testing, API automation, and CI reliability. See when to move beyond public Mailinator email workflows.
Read more technicalMailHog Tutorial: Local SMTP Capture, mhsendmail, and CI Handoff
Set up MailHog with Docker, capture outbound mail locally, test with mhsendmail, and move from localhost checks to reliable CI email workflows.
Read more technicalMailCatcher Introduction: Local Email Debugging and Migration Path
Learn what MailCatcher does, where it helps in local testing, its limitations, and how to move to shared CI-ready email testing workflows.
Read more technicalHow to Test if a Mail Server Supports STARTTLS
Verify STARTTLS support with OpenSSL, interpret SMTP capability responses, and validate TLS/auth behavior safely before production rollout.
Read more technicalHow to Test an SMTP Relay (Open Relay Checks + Secure Validation)
Test SMTP relay behavior safely using EHLO, MAIL FROM, RCPT TO, and authenticated flows to detect open relay risk and prevent abuse.
Read more technicalHow to send a test email in Mailchimp and validate it like a QA team
Step-by-step Mailchimp test email workflow with a QA checklist for links, personalization, spam risk, and inbox behavior.
Read more technicalFree email testing tools in 2026: what to use first, what to upgrade later
A practical guide to free email testing tools for QA and engineering teams, including limits, risks, and upgrade triggers.
Read more technicalFixing SMTP 550 Errors (550 5.1.1, Relay Denied, Policy Rejection)
Diagnose and fix SMTP 550 errors with a practical troubleshooting matrix for recipient issues, relay policy, auth setup, and sender reputation.
Read more technicalFake SMTP Server Setup for Testing (Local + CI Pattern)
Set up a fake SMTP server for testing, validate send flows safely, and move from local-only checks to production-grade CI email validation.
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