Software We Make
Open-source infrastructure software built for mission-critical email operations
go-emailservice-ads
Enterprise Mail Routing Fabric
Super modern perimeter and internal mail hub system built in Go. Deploy as a next-hop behind Postfix for internal routing, or run in clustered mesh mode for a fully-featured perimeter and internal mail hub combined. Kubernetes-native with enterprise-grade security, compliance monitoring, and disaster recovery capabilities.
Key Features
- β Multi-tier Queue System - 5 priority tiers with 1,050 workers
- β Advanced Security - DANE, SPF, DKIM, DMARC enforcement
- β Smart Routing - Divert/Screen Proxy for compliance
- β Disaster Recovery - WAL-based crash recovery
- β Kubernetes Native - Cloud-ready architecture
- β Compliance Ready - GDPR, HIPAA, SEC/FINRA support
Deployment Architectures
π· Postfix Perimeter Mode
Run Postfix at the perimeter for initial SMTP reception, then forward to go-emailservice-ads as your next-hop internal mail hub.
βΈοΈ Clustered Mesh Mode
Deploy as a fully-featured perimeter and internal mail hub in a clustered mesh architecture. No Postfix required.
Technology Stack
Real-World Use Cases
Legal Holds
Silent mail redirection for investigations without user notification. Complete audit trail with SHA-256 hashing.
Executive Oversight
Transparent BCC monitoring for compliance teams with no header modification or user awareness.
High Volume Processing
Process millions of messages per day with multi-tier queuing and automatic retry scheduling.
Regulatory Compliance
Built-in support for GDPR, HIPAA, and SEC/FINRA requirements with immutable audit logs.
AfterSMTP Protocol
Next-Generation Mail Transport Protocol
Revolutionary mail protocol using QUIC/HTTP3 transport, gRPC bidirectional streaming, and blockchain-based message verification. Native integration with msgs.global infrastructure for cryptographic identity management, immutable audit trails, and zero-RTT connections.
Key Features
- β QUIC Transport - HTTP/3 with multiplexing and congestion control
- β gRPC Streaming - Bidirectional real-time message flow
- β Blockchain Ledger - Substrate-based immutable audit trail
- β DID Identity - Decentralized identifier management
- β Legacy Bridge - Seamless SMTP compatibility layer
- β Enhanced Security - MTA-STS, DANE, TLS Reporting, ARC
Protocol Architecture
Transport Layer
QUIC protocol (UDP-based) with multiplexing, zero-RTT, and improved congestion control over legacy TCP.
Application Layer
gRPC with Protocol Buffers for efficient binary serialization and native bidirectional streaming.
Identity Layer
Blockchain-based DID verification with Ed25519 signing keys and X25519 encryption keys.
Audit Layer
Immutable ledger records with SHA256 content hashing for tamper-proof message verification.
AMF (ADS Mail Format)
Next-Generation Email Storage Format
Modern, versatile email file format designed to replace .eml, .msg, and .mbox. Built-in compression, encryption, signing, and rich metadata support. JSON-based for easy parsing and extensibility with streaming support for large messages.
Key Features
- β JSON-Based - Easy to parse, extend, and debug
- β Encryption - AES-256-GCM, PGP, S/MIME support
- β Signing - RSA, ECDSA, Ed25519 signatures
- β Compression - Gzip/Zstd for 60-90% size reduction
- β Rich Metadata - Labels, tags, threading, AI analysis
- β Compatible - Convert to/from .eml and .mbox
File Formats
Advanced Features
Calendar Events
Native iCalendar integration for meeting invitations, RSVPs, and calendar synchronization.
AI Metadata
Sentiment analysis, classification, entity extraction, and automated categorization built-in.
Blockchain Verification
Immutable audit trail with blockchain anchoring for legal compliance and tamper detection.
Streaming Format
JSONL streaming for large messages and incremental processing without memory overhead.
Why Replace .eml and .mbox?
- β No encryption
- β Limited metadata
- β MIME complexity
- β Poor compression
- β Built-in encryption
- β Rich metadata
- β JSON simplicity
- β 60-90% compressed
MailScript
Universal Email Filtering Engine
Starlark-based mail filtering that runs anywhere. Test offline, process mailboxes, or run as an SMTP proxy gateway. Integrate MailScript into ANY email infrastructure without vendor lock-in. The nuclear option for email filtering.
Key Features
- β Standalone Binary - No dependencies on other mail systems
- β SMTP Proxy Mode - Universal gateway for ANY mail server
- β Offline Testing - Develop and test rules before production
- β gRPC Integration - Non-mail apps can submit messages
- β Mailbox Processing - Import and filter mbox/maildir files
- β JSON Output - Perfect for CI/CD pipelines
Command Modes
π§ͺ Test Mode
Offline rule testing with custom headers, bodies, and spam scores. Develop filters without production risk.
π¦ Process Mode
Batch process mbox and maildir files with filtering rules. Perfect for migration and analysis.
π Proxy Mode
Full SMTP proxy server on ports 3025/3587. Universal filtering gateway in front of ANY mail server.
π» REPL Mode
Interactive development environment for rapid prototyping and debugging of filtering rules.
Use Cases
Email Service Providers
Add value-add filtering without touching core infrastructure. Per-customer rule customization.
Corporate Mail Gateway
Enforce content policy and compliance with DLP rules, attachment size limits, and phishing detection.
CI/CD Integration
Validate filtering rules in pipelines with JSON output. Test before production deployment.
Security Research
Analyze spam and phishing patterns in mail archives. Custom detection rules for threat intelligence.
Quick Start
# Install curl -sSL https://raw.githubusercontent.com/afterdarksys/mailscript/main/install.sh | bash # Test offline mailscript test --script=spam-filter.star --from="spam@evil.com" --subject="Buy Now!" # Process mailbox mailscript process --script=filter.star --mbox=/var/mail/user --verbose # Run as SMTP proxy gateway mailscript proxy --script=filter.star --upstream=mail.example.com:25 --enable-tls
Built for the Community
We believe in open-source infrastructure. Both go-emailservice-ads and AMF are available on GitHub for organizations that need enterprise-grade email infrastructure without vendor lock-in.
Part of the AfterDark Systems ecosystem
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