exu

EVALinux Virtual Mail Administration Suite for CentOS Stream 10

exu is a lightweight, statically-compiled Crystal web daemon and CLI administration suite providing secure, sovereign virtual mail administration for Exim, Dovecot, and Caddy on CentOS Stream 10.

Key Capabilities

• 🌐 Web Dashboard SPA: Fast, modern web control plane with clean session login and logout.
• ⚡ Standalone CLI (eum): Native, statically linked command-line administration tool sharing exact RBAC parity.
• 🔐 Session-Based mTLS: Decoupled transport client certificate authentication with encrypted HMAC-SHA256 session cookies.
• 📁 FHS 3.0 & YAML 1.2: Standardized /etc/exu/ configuration hierarchy and human-readable exu.yaml database.
• 🛡️ Zero-.rpmnew Churn: Non-invasive modular Exim includes (/etc/exim/exu-*.conf) and Dovecot drop-ins (/etc/dovecot/local.conf).
• 🔒 Multi-Process Advisory Locking: POSIX flock synchronization preventing race conditions across concurrent Web and CLI operations.
• 🔑 DKIM, DMARC & DNS: Automatic RSA-2048 key generation, on-demand rotation, and copy-paste ready DNS records.
• 👥 Multi-Recipient Aliases: Comma-, semicolon-, or space-delimited forwarding with atomic single-recipient removal.
• 💾 Storage Retention: Domain decommissioning preserves mailbox spools (/var/mail/virtual/<domain>) by default.

Quick Start

1. Build Static Release Binaries

make release

2. Automated Host Setup

Run the idempotent setup script as root to configure dependencies, services, SELinux policies, and certificates:

sudo bash resources/usr/local/libexec/exu/setup.bash mail.example.com

3. CLI Management (eum)

# Provision a virtual domain and DKIM keypair
eum domain create example.com

# Create a virtual mailbox
eum user create admin@example.com

# Create a multi-recipient alias
eum alias create example.com support alice@example.com bob@example.com

# Display complete DNS configuration (MX, SPF, DKIM, DMARC)
eum domain dns example.com

Documentation

Comprehensive guides, specifications, and architecture records are available in the Sphinx Documentation Suite:

Development

# Compile development binaries locally
make build

# Run unit & integration test suite (39 specs)
make test

# Run Flaw security static analyzer
make lint

# Build unified Sphinx documentation & Crystal API reference
make docs

Contributing & Code of Honor

This project adheres to the Universal Code of Honor. Please review the Contributing Guidelines before submitting contributions. All changes are logged in the Changelog.

Authors

• Rénich Bon Ćirić (@renich) — Creator & Lead Architect
• Gemini AI — Pair Programmer & Co-developer