ZapFast

ZapFast is a free, open-source WhatsApp desktop client built in Rust instead of wrapping WhatsApp Web in a browser. It connects to an existing WhatsApp account as a linked device, with a dedicated interface for messaging on macOS.

WhatsApp chats in a lightweight desktop app

• Send and edit messages, reply, react, forward content, and share photos, files, GIFs, stickers, and voice messages.
• Search conversations and messages, filter chats, and use keyboard shortcuts to navigate and reply.
• Link multiple WhatsApp numbers and switch between them in one window.
• Play voice messages and supported H.264 videos within chats; unsupported video formats open in the system player.
• Keep receiving desktop notifications after closing the window, with unread counts in the Dock.
• Choose light, dark, system, or custom color themes.

Local history and important limitations

ZapFast saves message history in an encrypted local archive, with the archive key held in macOS Keychain. Downloaded media and some other local files are stored separately without that archive encryption. Older messages can be requested from the phone, which needs to be online for those requests.

The current downloadable release does not support voice or video calls, status posts, or full group administration. ZapFast is also an unofficial WhatsApp client: WhatsApp may restrict accounts using third-party clients, so the official app is the safer option if account access is critical.

The Mac download is signed and notarized, supports Apple Silicon and Intel, and requires macOS 11.0 or later. It is also available through Homebrew and is licensed under MIT.