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MAIL & COMMUNICATION · PRO TIER

Postalpro

Postal is a self-hosted SMTP relay / mail platform designed specifically for sending transactional and marketing email at scale — bounce handling, click tracking, webhooks, multi-tenant. Where Mailcow targets full mail server (inbox + outbox), Postal targets outbound-only programmatic email infrastructure.

Install via WHMCS → Visit postalserver.io ↗

📧 Mail & Communication Min 4096 MB RAM Port 5000 (http) Tier pro

// What it is

A closer look.

For SaaS founders who want to run their own SendGrid / Mailgun, Postal is the open-source answer.

// Use cases

What it's for.

Concrete scenarios where teams pick Postal over the SaaS alternative.

◆

Transactional email

password resets, order confirmations, notifications

◈

Marketing email at scale

bulk campaigns with tracking

◇

API-driven email

REST + SMTP API for app integration

▣

Multi-tenant email

host email infrastructure for multiple clients

▦

Bounce + complaint handling

process feedback loops automatically

// Who it's for

Built for these teams.

If your team profile matches one of these, Postal is a strong fit out of the box.

Profile A

SaaS founders

wanting independence from SendGrid/Mailgun

Profile B

Agencies

providing email-as-a-service to clients

Profile C

High-volume senders

with predictable VPS cost vs metered SaaS billing

Profile D

Privacy-bound orgs

keeping email infrastructure in-network

Profile E

Email engineers

who want full control over delivery infrastructure

// Differentiators

Why teams pick Postal.

When evaluating self-hosted options for this category, here are the dimensions on which Postal consistently lands above the alternatives.

✓MIT license — fully open
✓Built for scale — Ruby/Go architecture handles millions of messages
✓Click tracking — built-in tracking pixels + link rewriting
✓Bounce processing — automatic suppression list management
✓Webhooks — event firing on delivery / bounce / open / click
✓Multi-organization — tenant isolation for agency use

// Integrations

Connects to.

The stack you'll plug Postal into — services, protocols, and adjacent apps in the BluixApps catalog.

◇

API

REST + SMTP API for application integration

◈

Webhooks

fire on every email event

◆

Auth

local + OAuth (GitHub, custom OIDC)

▣

Bounce handling

automatic suppression with feedback loop processing

▦

Click + open tracking

built-in with privacy-friendly opt-out

▩

Templates

basic templating; pair with external system for advanced

▼

Queue management

RabbitMQ-backed for async send

// Adoption & deployment

Notable users & community

7k+ GitHub stars
Used by SaaS founders and agencies running their own email infrastructure
Active GitHub Discussions community
Backed by ATECH (UK) with sustainable maintenance
Featured in SendGrid-alternative guides

What we ship

Docker compose: Postal + MariaDB + RabbitMQ
Pinned ghcr.io/postalserver/postal:3.3 (release-tagged)
HTTPS via Let's Encrypt
Admin user via env config
Persistent volumes for MariaDB + RabbitMQ
DKIM signing configured per domain
Backup hook covers MariaDB + config

// Tips & operations

Run it properly.

Operational guidance from running this in production — what to do before you scale, what to lock down, what surprises people.

// PERFORMANCE

Reverse DNS + SPF + DKIM + DMARC

non-negotiable for delivery

// SECURITY

Warm up new IPs

gradual ramp from low volume; cold IPs get spam-flagged

// OPERATIONS

Monitor bounce rate

>5% = sender reputation issue; investigate

// RELIABILITY

Suppression list discipline

Postal manages this automatically; trust it

// DEPLOYMENT

Persistent MySQL + RabbitMQ

both essential

// SCALING

Multiple sender IPs

for high volume, multi-IP rotation helps deliverability

4096

// min ram (MB)

// min disk (GB)

5000

// access port

http

// protocol

pro

// bluixapps tier

see install script

// docker image

Project resources

Official sitepostalserver.io ↗

// Alternatives in Mail & Communication

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