Stalwart replaces the traditional Postfix + Dovecot + SpamAssassin + calendar-server stack with one Rust binary that speaks every standard mail and collaboration protocol natively. JMAP, IMAP4rev2, POP3, SMTP, CalDAV, CardDAV, and WebDAV all run inside the same process — no glue scripts, no sidecar daemons, no version conflicts between components. The pluggable storage architecture lets operators choose RocksDB for single-node deployments, FoundationDB for distributed clusters, PostgreSQL, MySQL/MariaDB, or SQLite for the data store, S3/MinIO/Azure Blob for message blobs, and Elasticsearch or Meilisearch for full-text search, with Redis or the internal engine backing rate limiters and session state. Security features include S/MIME and OpenPGP encryption at rest, automated DKIM key generation with DNS publication, DANE and MTA-STS transport security, automatic ACME TLS provisioning, granular ACLs, rate limiting, and IP banning. The browser-based admin console manages accounts, domains, groups, mailing lists, SMTP queues, DMARC/TLS-RPT/ARF reports, and every configuration object without touching a config file, while the self-service portal at /account gives end users password reset and encryption key management. Multi-tenant support with per-tenant quotas enables hosting-platform deployments, and coordinator-less clustering via Zenoh or NATS scales horizontally by adding nodes. Deploy via Docker or the standalone binary. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL v3 licensed.

Larasend gives Laravel teams a self-hosted transactional email platform that sends through their own Amazon SES or Cloudflare account while keeping the dashboard, delivery logs, and message data on their own servers. Send mail with a simple POST to the emails API, or point existing mailables and notifications at the Larasend transport with one environment variable and no code rewrite. Every message lands in an activity dashboard where you can filter by status, search recipients and message IDs, open a preview with headers and metrics, and resend failures in one click. Delivery, bounce, complaint, open, and click events stream back from the provider and update each message timeline, so a missing receipt becomes a traceable record instead of a support mystery. Suppression lists build themselves from bounces and complaints, and guardrails watch complaint rates and verified domains before reputation damage can spread. Scoped API keys with expiration and rotation keep each project separate, while workspace roles control who can view, send, and administer. When replies arrive, the shared inbox threads inbound and outbound mail into conversations your team can assign, snooze, annotate, and answer with attachments and drafts. Webhooks notify your other systems about deliveries and inbound mail, and reusable templates keep recurring notices consistent across projects. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

MailCheap is a newsletter app you host yourself that writes, sends, and publishes your issues while charging you only for the emails you actually send, not for subscribers who never open anything. Write in an editor with slash commands, images, and content boxes, or send Markdown and HTML emails through the API, then work through a pre-send review that flags subject, preview text, unsubscribe link, and sender problems first. Bring your audience with you: CSV exports from beehiiv, Substack, Mailchimp, Kit, MailerLite, Buttondown, Ghost, and EmailOctopus import with each reader's status and signup date intact. Imports clean themselves, dropping invalid, misspelled, duplicate, throwaway, and spam-trap addresses, and a server-wide never-email list keeps known bad addresses out of every future import, signup, and send. Sending protects your domain: new contacts receive issues in paced steps, sends pause when bounce or complaint rates climb, and Gmail spam rates are watched daily. Every issue becomes a page on your newsletter's website, with a signup form, author page, share images, and a sitemap. Run up to three newsletters per account, each with separate contacts and campaigns, and follow subscribers over time with open and click reports by inbox provider. AI agents can do anything the dashboard can through the MCP server, and scripts get the same reach through the REST API, with sending marked irreversible so agents ask first. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.

MillionSend is an open-source email platform you run yourself that sends transactional and marketing mail through your own AWS SES account behind a Resend-compatible API. Every message you send becomes a row in the dashboard, and every row opens into a timeline of SES events with the raw payload and the SMTP diagnostic when something bounces. Daily metrics chart sent, delivered, opened, clicked, bounced, and complained volumes against SES thresholds, and broadcasts stop on their own at five percent bounces or 0.1 percent complaints before Amazon can pause your account. Contacts live once for the whole team with custom properties and subscribe state, while segments and topics decide exactly who receives each broadcast. You compose broadcasts from reusable templates with per-contact merge fields, schedule them ahead, and cancel them while they wait. Applications that only speak SMTP send through the relay on port 2587 with an API key as the password, and HTTP integrations use idempotency keys, request logs with secrets redacted, and signed webhooks with a delivery history. Guided domain setup handles DKIM records, hard bounces and complaints are suppressed automatically, and every recipient gets an RFC 8058 one-click unsubscribe. Receiving and agent-ready inboxes are included in beta for mail sent to your verified domains. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.

Your entire mail system can live in one self-hosted suite with OpenMail, from SMTP, IMAP, and POP3 delivery to three-pane webmail and the admin console that runs it. Standard clients such as Thunderbird, Apple Mail, and phone apps connect over SMTP ports 25, 587, and 465, IMAP ports 143 and 993, and POP3 ports 110 and 995, while people use the three-pane webmail with folder tree, conversation list, and reading pane at port 3000. You read, write, reply, forward, batch-organize, drag messages between folders, filter stars, search sender, subject, and body text, and follow conversations threaded automatically by their References headers. The rich-text composer autocompletes recipients, accepts dragged attachments and pasted screenshots, saves drafts every 12 seconds, sends on a schedule, and inserts reusable templates imported from HTML or generated with AI. Any OpenAI-compatible endpoint can draft replies, translate mail into twelve languages, and summarize messages, with provider keys encrypted on your server. Administrators get real-time mail statistics with 14-day send and receive trends, user quotas and bans, multi-domain aliases and catch-all addresses, outgoing queue visibility, and audit logs. Adding a domain generates DKIM keys and copy-ready SPF, DKIM, and DMARC DNS records with one-click checks, while rule-based spam scoring, TOTP two-factor authentication, and role-based permissions protect accounts in ten interface languages including right-to-left Arabic and Urdu. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.