Mailspring:love_letter: A beautiful, fast and fully open source mail client for Mac, Windows and Linux.

Mailspring

Mailspring is a lightweight, high-performance open source email client for Mac, Windows, and Linux that combines a beautiful user interface with efficient resource usage. Built as an improved successor to Nylas Mail, it features a C++ sync engine that uses roughly half the RAM and CPU while maintaining zero idle CPU wake activity for extended battery life. The application's plugin architecture and TypeScript/React-based UI make it highly extensible and developer-friendly.

Key Features

• Unified Inbox: Consolidate multiple email accounts in one interface
• Advanced Scheduling: Snooze emails and schedule message delivery for optimal timing
• Mail Rules & Templates: Automate workflows with custom rules and reusable message templates
• Pro Analytics: Unlock link tracking, read receipts, and mailbox analytics with a subscription
• Client-Side Processing: All features run locally—your credentials never leave your computer

Use Cases

• Power Email Users: Manage high email volume with advanced productivity features and analytics
• Privacy-Conscious Users: Benefit from client-side processing with no cloud credential storage
• Developers & Customizers: Extend functionality through plugins, themes, and direct source code contributions
• Cross-Platform Users: Maintain consistent email experience across Windows, Mac, and Linux

Who Is It For

Mailspring is ideal for users who prioritize performance, privacy, and customization in their email client. It appeals to both everyday email users seeking a beautiful, efficient alternative to traditional clients and developers who want to extend their mail application through plugins and themes.