Unlimited agents, unlimited tickets, unlimited mailboxes, forever, on a $4 VPS - FreeScout's pricing inversion is why it became the most popular self-hosted Help Scout alternative, a PHP/Laravel help desk and shared inbox developed from scratch over eight years. The inbox deliberately behaves like Gmail or Outlook, so new support agents need close to zero training. The email-support core is genuinely complete: seamless IMAP/SMTP integration including modern Microsoft Exchange authentication, collision detection that warns when two agents open the same conversation, canned responses, auto-replies, internal notes, open tracking, starring, forwarding, merging, and moving conversations between mailboxes, phone-call logging, push notifications, and an auto-refreshing conversation list - plus screenshot pasting straight from the clipboard into replies. It's 100% mobile-friendly, fully screen-reader accessible, and translated into 28 languages. Beyond the core, an ecosystem of 100+ modules (mostly one-time $12-20 purchases) adds knowledge base, workflows with Gmail-filter-style automation rules, satisfaction ratings, time tracking, tags, custom fields, LDAP, Slack, WhatsApp and Telegram channels, and an API with webhooks - pay only for what your team needs. Web installer and updater included. AGPL-licensed.

Kurrier unifies email, calendars, contacts, and file storage in a single web interface that connects to any email provider you already use. The Next.js frontend with Nitro API worker deploys via Docker Compose on PostgreSQL and Redis, delivering a cohesive workspace where IMAP/SMTP mailboxes from Gmail, Outlook, or corporate servers sit alongside transactional providers like AWS SES, SendGrid, Mailgun, and Postmark. Automatic inbox building handles threads, attachments, sent items, and deletion sync through persistent background polling. The CalDAV backend enables full two-way calendar synchronization with iOS, macOS, Android via DAVx5, and Thunderbird, supporting event invitations, RSVP processing through the inbox, timezone-aware scheduling, and contact-aware attendee linking. CardDAV contacts sync bidirectionally across all devices with unified name, avatar, and email resolution. Kurrier Drive provides integrated file storage through WebDAV locally or S3-compatible backends for cloud storage. Multiple identities and domains let you manage several email accounts from different providers in one interface, with fast local search indexing subjects, senders, and content without dependency on external APIs. The API-first architecture exposes clean endpoints for automation and custom integrations. 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.

Mox offers a complete mail server stack in a single Go binary requiring no external dependencies. The quickstart command configures a working mail server with SMTP, IMAP4, webmail, and full DNS authentication in under ten minutes. SMTP handling includes a delivery server on port 25, a submission server for authenticated clients, and a queue with automatic retries and DKIM signing. IMAP4rev2 implementation provides full mailbox synchronization with CONDSTORE and QRESYNC for efficient offline clients, NOTIFY for multi-mailbox monitoring, MULTISEARCH across mailboxes, and TLS client certificate authentication via the EXTERNAL SASL mechanism. The built-in webmail provides browser-based reading and composing with message threading, attachments, and HTML rendering without requiring a separate web client. Email authentication implements SPF validation, DKIM signing and verification with automatic key rotation, DMARC policy enforcement with aggregate and failure reporting, DANE with DNSSEC-protected TLSA records, and MTA-STS for certificate verification. Junk filtering combines reputation-based sender scoring with Bayesian content analysis trained per account. The web administration interface manages domains, accounts, DNS records, TLS certificates, delivery queue, and real-time log viewing. Internationalized email addresses with EAI and IDNA support handle non-ASCII domains and mailboxes. Account autoconfiguration publishes settings for Thunderbird autoconfig and Outlook autodiscover. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Automate transactional and marketing messages across email, SMS, mobile push, WhatsApp, Slack, and custom webhooks from a single visual journey canvas. Dittofeed provides the capabilities of Customer.io or Braze while keeping customer PII within your own infrastructure and eliminating volume-based pricing entirely. The drag-and-drop journey builder creates multi-trigger automations with branching logic, wait nodes, random cohort splits for A/B testing, and local timezone delivery without writing code. User segments combine trait conditions, event history, and array-based filtering through AND/OR operators with real-time evaluation. Template authoring supports both a low-code visual editor and direct HTML/MJML input, with templates reusable across journeys and one-off broadcasts. Data flows in through Segment integration, Reverse ETL connections, or the REST API with Web, Node.js, and React Native SDKs. Message delivery routes through SendGrid, Amazon SES, Twilio, or SignalWire with per-channel analytics tracking opens, clicks, bounces, and unsubscribes. Authentication supports Keycloak, AWS Cognito, and GCP OAuth for enterprise SSO. Embeddable iframe and headless React components let SaaS platforms white-label journey builders into their own products. Deploy on RepoCloud with a dedicated VPS for full GDPR compliance under the MIT license.

Zero unifies Gmail, Outlook, and IMAP accounts into a single AI-enhanced inbox with keyboard-driven navigation that matches premium email clients in speed. Backed by 10,000+ stars and positioned as the alternative to Superhuman, it keeps your email data in your own PostgreSQL database while LLM agents handle categorization, priority sorting, draft composition, and natural language mailbox queries. You choose whether models run locally or through cloud providers you control. The Next.js and React interface delivers customizable keyboard shortcuts for every action: reading, archiving, labeling, composing. A WorkflowEngine defines automated multi-step rules including label application, bulk archiving, and conditional routing based on sender, subject, or content analysis. Built on Drizzle ORM with Better Auth handling Google OAuth, styled with TailwindCSS and Shadcn UI components, the interface is polished without being bloated. MCP integration exposes email management tools to external AI assistants for programmatic inbox control through standardized protocols. The Nizzy CLI handles environment configuration, database synchronization, and development server orchestration. Deploys via Docker Compose with a single database initialization command. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Built as a developer-first alternative to SendGrid, Mailgun, and Postmark, Posta delivers a complete self-hosted email infrastructure platform handling both outbound delivery and inbound reception through a single HTTP API with official SDKs for Go, PHP, and Java. The Go backend processes email through Redis and Asynq with automatic retries, priority queues, and async delivery while PostgreSQL stores templates, contacts, campaigns, and delivery analytics. Outbound features include versioned multi-language templates with variable substitution and stylesheet inlining, bulk campaigns with subscriber targeting and A/B testing per-variant metrics, scheduled timezone-aware delivery with draft/paused/cancelled lifecycle states, email address verification checking syntax, MX records, disposable domains, and role accounts, plus web view links with signed expiring URLs and one-click unsubscribe headers. The built-in SMTP receiver with TLS handles inbound email at your domains, parses messages and attachments, scores spam, and forwards structured payloads to your application via HMAC-verified webhooks with real-time SSE notification streams. The Vue-based dashboard manages templates, SMTP server pools, domains, contacts, API keys, campaigns, and email logs with dark and light mode support while admin-level platform metrics expose delivery rate trends, bounce rate graphs, and latency percentiles alongside Prometheus integration and daily health reports. Deploy via Docker with PostgreSQL and Redis. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

DispatchMail is an SuperHuman alternative and delivers a self-hosted AI email assistant that processes your Gmail inbox through configurable OpenAI prompts without sending data to third-party cloud services beyond the LLM API itself. The Flask backend connects to Gmail via IMAP, retrieves new messages according to your schedule, and routes them through customizable whitelist rules based on sender address, subject keywords, or natural language descriptions before AI processing begins. Two distinct prompt configurations control behavior — the Reading Prompt instructs how the AI should analyze and classify incoming messages, while the Draft Prompt defines how responses should be composed, letting you maintain consistent tone and policy across all automated replies. Whitelist filtering ensures the AI only processes messages you explicitly authorize, preventing unnecessary API costs and keeping sensitive emails out of the LLM pipeline entirely. The React web interface provides inbox management with message previews, AI-generated summaries, draft editing with human-in-the-loop approval before sending, and configuration panels for prompts and rules. Automatic labeling and archival organize processed messages into categories without manual intervention. The sender research feature uses LLM-powered deep analysis to build background profiles of email contacts. All email content, credentials, and processing results persist in a local SQLite database with zero cloud storage dependencies. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache-2.0 licensed.

Email discussion lists - the venerable listserv pattern where one address relays to a whole group - without the notorious setup pain of Mailman or Sympa: that is Gray Duck Mail. Its architectural trick is requiring no mail server of your own: the C#/ASP.NET Core app monitors a POP3 inbox at any external email host supporting POP3/SMTP and aliasing, relays each incoming message to all list members via SMTP, and archives it for browsing in the web interface. Replies route back to the entire group automatically. The tedious parts of list management are handled by convention: dedicated aliases process join requests, subscription confirmations, and unsubscribes, while a bounce alias in the return-path catches delivery failures so dead addresses get handled instead of silently rotting. The web administration interface creates and removes lists, manages contacts, browses message archives, and imports or exports the local database for backup. GPLv3-licensed, Docker-distributed, and fully code-documented, it targets exactly the groups email still serves best - neighborhoods, schools, congregations, workplaces, and families - where one message keeping everyone in the loop beats yet another app nobody wants to install.