OpenHuman

Mail by OpenHuman is a keyboard-first Gmail client for macOS, with AI that runs on your Mac.

Core features · Download · Build · CLI · Contributing

OpenHuman is an open-source, clean-room clone of Superhuman.

It is Swift-native, runs locally (including its AI features), and is agent-ready, with a command-line interface for external AI agents.

This is a very early alpha, so expect bugs. It runs on Apple silicon Macs with macOS 26.0 or later. Its author has only tested it on macOS 27 on Apple silicon. Features that depend on macOS 27, such as Apple's on-device model, degrade gracefully on macOS 26 and offer alternatives. It is built with Xcode 27 and Swift 6.4.

Download the signed and notarized release, or build from source. Maintainers can follow the release guide to build, verify and publish a DMG. Homebrew installation will be announced when ready.

_{The inbox, split into Important, Newsletters and Other. Every screenshot here shows invented sample data.}

Reply inline, then send now, send later, or get a reminder.	A few seconds to take back a send, in the Dark theme.
Search with Gmail operators such as from: and has:attachment.	Your calendar beside the conversation, with an event drafted from the email.

Core features

• Keyboard first. Superhuman-style shortcuts, a command palette on ⌘K, and shortcuts you can change.
• Split inbox. Important mail apart from the rest, plus your own splits made from any search. “Why is this here?” explains where a conversation landed.
• Snooze, reminders and send later. Snooze a conversation, get a reminder if nobody replies, schedule a send, and undo a send while its undo window is open.
• Search. Gmail search syntax, related matches from an index built on your Mac, and a Gmail lookup for mail that is not on your Mac yet.
• AI on your Mac. Summaries, quick replies, rewrites and Ask AI about your mail. AI runs on your Mac by default, and providers that would send mail off your Mac stay off until you allow them. Every prompt can be read and edited in Settings.
• Calendar beside your mail. Your Google Calendar day next to the conversation, events created from an email, and free times inserted into a reply.
• Less noise. Mute a conversation, block a sender or a domain, unsubscribe, and clear out old mail with Get me to zero.
• Safe by design. Mail never deletes mail permanently, empties Trash or Spam, or changes Gmail settings or filters, and ⌘Z undoes changes; a sent message can be taken back during its undo window.
• Themes. Six built-in themes, and your own as plain JSON files.
• A CLI for agents. openhuman reads the same local mail, writes drafts for you to review, and never sends. It includes an MCP server. See the CLI documentation.

Download and install

Download version 0.1.0. This early alpha release is a Developer ID signed, Apple-notarized DMG for Apple silicon Macs running macOS 26.0 or later.

Open the DMG and drag OpenHuman Mail to Applications. On first launch, follow onboarding to create and import your own Google Desktop app OAuth client. No shared Google client is bundled.

Opening an unsigned build

macOS may block unsigned builds because they are not notarized by Apple. To open one, try to open the app once. Then open System Settings, click Privacy & Security, and scroll to Security. Click Open Anyway, enter your login password, and click OK. The Open Anyway button stays available for about an hour after you first try to open the app.

Local development builds and CI development artifacts use ad-hoc signing and are not notarized by Apple.

Build

Tools/bootstrap.sh
Tools/ci/build-app.sh
open Apps/Mail/Mail.xcodeproj

For the CLI:

cd Packages/OpenHumanCLI
swift build -c release --product openhuman
.build/release/openhuman --help

See Build and test, CLI documentation, and Contributing. First-launch onboarding explains how to create and import your own Google Desktop OAuth client. Mail and settings are stored locally on your Mac. Sign-in credentials are kept in your Keychain.

Source layout

Directory	Contents
Apps/Mail/	macOS application, XcodeGen project, and application tests
Packages/	Shared Swift packages, mail storage and sync, UI, AI, and CLI
Tools/ci/	Build, test, packaging, and architecture checks
Tools/release/	Versioning, Developer ID signing, notarization, and DMG tooling
docs/cli/	CLI user guide, agent guide, and JSON schema
skills/openhuman-mail/	Agent integration for the local CLI

License

Apache License 2.0.