Kestrel Mail

Documentation

Acknowledgements

Kestrel Mail is built with the help of several open-source projects and platform technologies. This page is meant to be a stable public acknowledgement surface, especially for in-app links.

Updated March 26, 2026

App foundations

  • SwiftMail powers the IMAP and SMTP foundation Kestrel builds on for mail transport work.
  • SwiftSoup helps with HTML parsing and cleanup workflows that support safe message rendering.
  • llama.cpp underpins the enhanced local model-pack path used for optional on-device summaries.

Website tooling

  • Astro powers the public website and documentation surface.

Platform technologies

Kestrel Mail also relies heavily on Apple platform frameworks across SwiftUI, WebKit, Quick Look, Contacts integration, authentication flows, and Foundation technologies for the macOS experience.

Thank you

Open-source maintainers and platform teams make it possible to build a focused native product without reinventing every layer from scratch. Kestrel Mail is grateful for that work.