BizFirst Email System — Developer Guide

What is BizFirst Email System? A plugin-based email delivery system supporting SMTP, AWS SES, and Gmail OAuth2. Each tenant configures their own email provider via named credentials stored in an encrypted vault. Dispatchers map credentials to providers and handle delivery. Extensible architecture allows adding new providers without modifying core code.

Getting Started

Quick Start (5 min)

Send your first email in 5 minutes. Best for new users.

First-Time Configuration

Step-by-step setup walkthrough for initial configuration.

Credentials & Security

AES-256-GCM encryption, vault design, multi-tenant isolation.

Email Providers

SMTP Configuration

Office 365, Gmail, custom SMTP servers. Host, port, SSL/TLS setup.

AWS SES Setup

Amazon's email service. IAM credentials, regions, sender verification.

Gmail OAuth2

Google OAuth2 authentication. Token refresh, scopes, service account setup.

Build Your Own Provider

Implement a custom email provider in 10 steps. Complete step-by-step guide.

Configuration & Deployment

Tenant-Specific Providers

Isolate provider configuration per tenant. Named credentials, per-tenant secrets.

Production Deployment

Multi-tenancy, failover, monitoring, high availability, disaster recovery.

Switching Providers Mid-Production

Change providers without downtime. Failover, traffic shifting, rollback procedures.

Advanced Topics

Advanced Dispatcher Patterns

Offline storage, logging, multi-provider routing, IP pooling, blockchain ideas.

Sample JSON Configurations

Complete JSON examples for all providers and credential types.

Roadmap & Community

Future Providers

SendGrid, Mailgun, Microsoft Graph API, Braze, and more. Implementation roadmap.

Request New Provider

Submit provider requests and vote on priorities. Community-driven roadmap.

Key Features

Secure

AES-256-GCM encryption, OAuth2 support, audit logging, secrets never logged.

Pluggable

Plugin architecture. Add providers without modifying core code.

Multi-tenant

Complete tenant isolation. Per-tenant credentials and configuration.

Production Ready

Three providers (SMTP, SES, Gmail). HA, failover, monitoring.

Architecture at a Glance

Layer	Components	Responsibility
Application	Auth Service, Notification Service	Calls `IEmailService.SendAsync()`
Core Orchestration	`EmailService`, `EmailDispatcherFactory`	Credential lookup, provider dispatch, result mapping
Providers	SMTP, SES, Gmail dispatchers	Type mapping, credential casting, service invocation
Integration Services	`ISmtpEmailService`, `ISesEmailService`, `GmailMessageService`	Actual email delivery (MailKit, AWS SDK, Google API)
Infrastructure	Credential Vault, Encryption, Database	Named credential resolution, AES-256-GCM encryption

Currently Supported Providers

Provider	Protocol	Cost	Setup Time	Status
SMTP	SMTP/STARTTLS	Varies (free to paid)	5 minutes	✅ Production
AWS SES	REST API	$0.10 per 1000	15 minutes	✅ Production
Gmail OAuth2	REST API (Google)	Free (quota-limited)	20 minutes	✅ Production

Navigation Guide

New to the system? Start here:

Quick Start — Get sending in 5 minutes
Choose your provider: SMTP, SES, or Gmail
First-Time Configuration — Detailed setup steps
Credentials Design — Understand security
Production Deployment — Go live safely

Building a custom provider? See Bring Your Own Provider for step-by-step instructions.

Advanced patterns? Explore Advanced Dispatcher Patterns for offline queuing, multi-provider routing, IP pooling, logging, and blockchain approaches.

Other Infrastructure Guides

Storage & S3

Multi-tenant, content-addressable file storage. MinIO/S3 backend with deduplication and lifecycle management.

Status: 🟢 Production Ready | Version: 1.0 | Last Updated: 2026-05-28