Foundry376/Mailspring

Health v2 · maintenance only

Adoption not part of the score

17761 stars · 1023 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

Mailspring is a fully open source desktop email client for Mac, Windows, and Linux, built with Electron, React, and TypeScript, with a C++ sync engine based on Mailcore2. It supports IMAP, Gmail, Office 365, and other major providers with features like unified inbox, snooze, send later, templates, and a plugin/theme architecture.

Use cases

• manage multiple email accounts in one unified inbox
• schedule emails to send later
• snooze emails and set follow-up reminders
• search across all connected mail accounts
• customize an email client with plugins and themes
• use a free open-source alternative to Outlook or Spark
• track read receipts and link clicks on sent email

When to choose

• you want a beautiful, fast, cross-platform desktop mail client that is open source
• you need IMAP/SMTP or Office 365 support with local sync and credentials kept on-device
• you want to extend or theme your email client via a plugin architecture

When to avoid

• you need a mobile email client (Mailspring is desktop-only)
• you require calendar or contact sync beyond basic support
• you want a fully free product including read receipts and link tracking (those require the paid Pro subscription)

Facets

application · maturity active

email gui search-engine plugin-system email developer-tools cross-platform desktop-applications windows cross-platform mail-client imap smtp unified-inbox open-source-email react typescript sync-engine macos linux electron

Member repositories

For agents

markdown · JSON · MCP: product_card(name="Foundry376/Mailspring")