In development · pre-release

Unkai Mail

A modern desktop mail client built for people who live inside Nextcloud.

The pitch

Existing mail clients treat Nextcloud like an afterthought — if they handle it at all. Unkai Mail flips that. Talk, Files, Contacts, and Calendar are first-class citizens of your inbox.

What makes it different

Four ideas, executed seriously.

Nextcloud, first-class.

Create Talk rooms from a thread, attach files directly from your cloud, and keep contacts and calendar synced. No plugins.

Standards-based.

IMAP, SMTP, JMAP, CardDAV, CalDAV. Your data stays portable and self-hostable.

Native performance.

Rust on Tauri 2. Fast to start, light on memory, respectful of your battery.

Modular architecture.

A workspace of focused crates — protocol handling, sync, storage, UI — cleanly separated.

Under the hood

The stack.

A Rust workspace of focused crates, wrapped in a Tauri 2 shell. Each layer is testable in isolation, so the messy parts of mail stay contained.

Core: Rust workspace
Shell: Tauri 2
Build: Vite
Targets: macOS · Linux · Windows
Storage: SQLite
Protocols: IMAP · JMAP · CalDAV · CardDAV

Where we are

Pre-release. Foundations first.

We're focused on protocol handling, sync, and storage — the foundations that make everything else possible — before opening it up to early users. Follow the blog or the GitHub repo for progress updates.

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