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On the recordRead 8 Oct 202621 facts
smtp4dev
On the record
- API
- The project provides an OpenAPI/Swagger API.github.com · read 8 Oct 2026
- API and automation
- An API is available for automated tests and external applications, with endpoints for messages, sessions, mailboxes, and server status and configuration.github.com · read 8 Oct 2026
- Client integration
- Applications can connect by SMTP using the host and port where smtp4dev runs; the documentation gives localhost and port 25 as defaults.github.com · read 8 Oct 2026
- Configuration
- Settings can be changed in the UI, appsettings.json, environment variables, or command-line arguments.github.com · read 8 Oct 2026
- Deployment
- Installation options include winget, Docker/OCI images, a .NET global tool, and GitHub release downloads.github.com · read 8 Oct 2026
- Docker security
- The maintainer warns that Docker-published ports may be accessible outside the host and recommends binding to 127.0.0.1 when external access is not needed.github.com · read 8 Oct 2026
- Email protocols
- It supports SMTP and provides IMAP and POP3 access to retrieve and delete messages.github.com · read 8 Oct 2026
- License
- The GitHub repository identifies the project license as BSD-3-Clause.github.com · read 8 Oct 2026
- Mail handling
- Users can configure multiple mailboxes and routing rules, compose or reply to messages, and relay messages with optional automatic rules.github.com · read 8 Oct 2026
- Mail protocols
- It supports SMTP, IMAP, and POP3 for receiving, retrieving, and deleting test messages.github.com · read 8 Oct 2026
- Message inspection
- Features include SMTP session logs, multipart MIME inspection, HTML rendering, validation, and compatibility reports.github.com · read 8 Oct 2026
- Platforms and distribution
- The project offers Windows and Linux binaries and containers, and a .NET SDK tool for platforms where the SDK is available; its README also names Windows, Linux, and Mac OS X.github.com · read 8 Oct 2026
- Purpose
- smtp4dev is a fake SMTP server for development and testing, letting developers test email without sending it to real customers.github.com · read 8 Oct 2026
- Security configuration
- The Docker security guide warns that published ports may expose captured emails externally and recommends binding ports to localhost unless outside access is needed.github.com · read 8 Oct 2026
- Security features
- It supports TLS/SSL with implicit and STARTTLS modes, automatically generated self-signed certificates, and optional authentication.github.com · read 8 Oct 2026
- SMTP debugging
- The product provides SMTP session logging and supports scripting expressions for error simulation.github.com · read 8 Oct 2026
- Testing integrations
- The testing guide covers programmatic use with the REST API, SignalR email notifications, Testcontainers examples for multiple programming languages, and direct use of the SMTP server component in .NET.github.com · read 8 Oct 2026
- Testing tools
- The interface includes a viewport size switcher for simulating mobile email views and a terminal UI with full functionality.github.com · read 8 Oct 2026
