email-deliverability

Open-source, self-hosted email deliverability testing platform

Next generation SMTP mailer plugin for WordPress. Trusted by over 300,000 sites by WPExperts.io

Collection of Postmark AI skills

📧 Never end in spam with the world's most comprehensive email deliverability checklist

SALES · OUTBOUND — Own your sending infrastructure instead of renting it. Claude Code skill + playbook for self-hosted cold email.

Open-source Apollo alternative: cold-outreach engine that verifies every mailbox before sending. Email discovery, SMTP verification, bounce-proof delivery. Self-hosted or hosted. Free Hunter.io / Instantly / Clay alternative.

77+ free, open-source GTM skills for Claude Code, Claude.ai, Codex, Cursor and every AI agent: ICP research, prospecting, buying signals, cold email, LinkedIn outreach, deliverability, reply handling, deals, RevOps, SEO and AEO.

Email Deliverability Management Library - Email Authentication, Reputation Monitoring, Email List Hygiene, IP Warming Tools & Unified Interface to manage all.

Check domains for email blacklists (Spamhaus, URIBL, SURBL, ZEN, SpamCop, Barracuda) + missing SPF/DKIM/DMARC. Pure DNS, zero deps, no API keys. Ships as a Claude Code skill + standalone CLI.

Deutscher Mail-Tester für Nicht-Techniker: SPF, DKIM, DMARC, Sperrlisten und Spam-Score 0 bis 10, mit Klartext-Anleitung für den eigenen Anbieter. Unbegrenzt kostenlos, Server in Deutschland.

Open-source skills for running B2B outbound on Apollo.io, in Claude Code, Codex, or any AI chat. Built by Creatop.

The open-source AI SDR engine any agent can drive. MCP server, Agent Skill, CLI and REST API for finding leads, reading buying signals, writing and sending email and LinkedIn outreach, handling replies and reporting.

Gmail Postmaster Tools (v2 API) as an MCP server — domains, traffic metrics & sender compliance in Claude, Cursor, and any MCP client. Bring your own Google OAuth. Zero dependencies.

Outlook.com SNDS (Smart Network Data Services) as an MCP server — OAuth sign-in, IP Data & IP Status reports in Claude, Cursor, and any MCP client. Zero dependencies.

Cold email deliverability scanner — 400+ spam trigger words, dual scoring (deliverability + ICP clarity), clean rewrite. Claude Code skill.

MailboxValidator CodeIgniter4 library enable users to block disposal email, detect free email and validate if an email is valid

Open-source bulk email platform. Send 100K+ personalized emails via Gmail SMTP or AWS SES with tracking, analytics, smart throttling, and zero spam.

MailboxValidator Ruby module enable users to block disposal email, detect free email and validate if an email is valid

MailboxValidator CodeIgniter library enable users to block disposal email, detect free email and validate if an email is valid

A powerful IP Blacklist Remover and Checker tool by ApexSofteck that helps developers and system administrators detect blacklisted IPs, monitor reputation, and automate removal from DNSBL/RBL services to ensure secure communication and better email deliverability.