Zephium

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Zephium is an open-source browser built in Rust on your operating system's own web engine: WebKit on macOS, the engine Safari uses, and WebView2 on Windows. It is not a fork of Chromium or Firefox. It blocks ads and trackers natively, runs Chrome extensions, and puts tasks, notes and your time on the web one click away. The download is about 30 MB.

One switch away is Work. Your work already happens in the browser, where your tabs, logins and history are. Work brings agents there instead of asking you to move somewhere else, and lets you watch them do it.

Work

Describe an outcome in your own words: plan a trip, compare vendors, design a system, fix a bug. Work takes it from there on a canvas, and you see every step.

• It starts from what you already have. Work recalls what it knows about you, searches your history when it helps, and loads the right skill for the job. Each step appears on the canvas as it happens.
• Helpers work in parallel, in the open. For a trip, one helper looks for flats while another checks visas and a third compares flights. They browse live pages you can watch, and any source opens in a pane beside the canvas.
• Results stay on the canvas. Comparisons, tables, charts, diagrams, plans, code and documents are laid out where you can read them. They are not lost in a chat scroll.
• A plan becomes your day. One click turns each step of a plan into a task linked back to the Work. Anything worth keeping can be saved as a note.
• It reaches past the browser. Work reads and edits the folders you grant, runs commands, and hands larger coding jobs to Claude Code or Codex. It connects to MCP servers such as Linear, Notion, Sentry, Stripe and Figma, and to command-line tools such as gh.
• You stay in charge. Anything that posts, merges or changes something waits for your OK.
• Bring any model. Use your own keys for Anthropic, OpenAI, Google Gemini, xAI, Mistral, DeepSeek, Groq, Cerebras or OpenRouter, or run a model locally through Ollama, LM Studio or any OpenAI-compatible server. Keys live in your system keychain. Or sign in to Zephium AI and skip the keys: it picks the right model for each step, and you start with free credits (pricing).

Work ships with 25 skills, including trip planning, research, compare and choose, plan my day, fix a bug and weekly status. You can write your own.

Ask Zephium

An assistant in the sidebar, on ⌘ E (Ctrl E on Windows). It reads the page you are on and answers about it, points at what is worth your time, and opens what you choose in new tabs. Ask it to take a few steps on the page, or to restyle a site you visit every day, and it does it in place. When a job outgrows a chat, Continue in Work carries it to the canvas, with the page along.

Browse

Fast and light

• Native WebKit on macOS and WebView2 on Windows, so pages run on the engine your system already keeps up to date.
• Inactive tabs go to sleep and wake when you return, so memory stays low with many tabs open.
• A native ad and tracker blocker, on by default, built on Brave's adblock-rust with EasyList, EasyPrivacy and uBlock Origin's filters. Requests are stopped before a page can make them, and you can hide anything else on a page with a click.

Designed to live in

• A new tab that opens onto the sky, by day or by night with your theme, with your time, your focus and the day's tasks along its foot.
• Vertical tabs in a quiet sidebar, with spaces, profiles, pinned tabs, folders and split view.
• Liquid Glass on macOS 26 and Mica on Windows 11.
• A launcher on ⌘ ⇧ Space (Ctrl Shift Space on Windows) reaches tabs, history, notes and commands from anywhere on your desktop. Anything you type there can become a task.
• Every keyboard shortcut can be changed.

Extensions

Install extensions straight from the Chrome Web Store. Twenty popular ones are verified to work well in Zephium and are a click away in the extension manager, including 1Password, Bitwarden, Grammarly, DeepL, Dark Reader, Vimium, SponsorBlock, Raindrop.io, Notion Web Clipper and Refined GitHub.

Bring everything with you

The welcome flow imports from Chrome, Safari, Arc, Zen, Firefox, Brave and Edge.

Built in

Private by default

• No Zephium telemetry. Zephium has no first-party browsing telemetry. On Windows, Microsoft Edge WebView2 sends required diagnostic data to Microsoft; optional diagnostics follow Windows settings. Microsoft Defender SmartScreen is on by default and can send website addresses and download information to Microsoft for reputation checks. Settings → Privacy offers a SmartScreen switch (effective after restarting Zephium) and a link to Windows diagnostic settings. If Windows cannot apply OFF, the switch is shown as managed and the browser continues to start. An unavailable startup preference read keeps SmartScreen on and shows that launch fallback in Settings. Turning either optional diagnostics or SmartScreen off does not disable required WebView2 diagnostics. See Microsoft's WebView2 data and privacy documentation.
• No account needed. History, tasks, notes, memory and time live on your device. An account is only needed for Zephium AI. Update checks, protection lists and extension services can contact their servers without signing in.
• Zephium AI keeps no content. Requests pass through to the model that answers them. We count usage for your plan, never store prompts, answers or pages, and never see your card.
• Private windows keep nothing once they close.

Download

Platform	Architecture	Installer	Requires
macOS	Apple Silicon	Zephium-macOS-arm64.dmg	macOS Sonoma 14 or later
Windows	x64	Zephium-Windows-x64-setup.exe	Windows 10 or 11

Windows builds are not code-signed yet, so SmartScreen may show "Windows protected your PC". Choose More info, then Run anyway. Signing is on the way.

Zephium downloads updates in the background and installs them when you choose Relaunch to update. All releases are on the releases page.

What's next

• Linux and Intel Macs.
• Code-signed Windows builds.
• More extensions verified to work, and native extensions built into Zephium.
• And much more.

Build from source

Prerequisites:

• Rust through rustup. The toolchain pinned in rust-toolchain.toml installs itself on first use.
• Node.js, at the version in .node-version.
• pnpm, through Corepack: corepack enable.
• The Tauri prerequisites for your platform: Xcode Command Line Tools on macOS, or the Microsoft C++ Build Tools and WebView2 on Windows.

git clone https://github.com/zephium-browser/Zephium.git
cd Zephium
pnpm install --frozen-lockfile
pnpm dev

Development builds use their own app.zephium.dev profile, so they do not touch the data of an installed Zephium. Linux is not supported yet. See CONTRIBUTING.md before opening a pull request.

Architecture

• Untrusted pages run in raw native WebViews, apart from the privileged Svelte interface that draws the browser.
• A Rust core owns tabs, storage, the blocker, extensions and agents.
• Each profile has its own isolated website data and Zephium-owned history, session and favicon data.
• The network blocker is native and built on Brave's adblock-rust.
• Narrow in-tree adapters for Tauri and Wry handle storage policy, WebView construction, callbacks and teardown.

Read more in docs/architecture.md and docs/security-model.md.

Contributing

Zephium is maintained by one person with a clear product direction, so please discuss larger changes before writing them. CONTRIBUTING.md explains what gets merged and how. Questions and ideas are welcome on Discord.

Security

Please report vulnerabilities privately, not in a public issue. See SECURITY.md.

License

Zephium is licensed under the Mozilla Public License 2.0.

The bundled EasyList and EasyPrivacy filter lists are used under CC BY-SA 3.0, and uBlock Origin's filters and quick fixes, unmodified, under GPL-3.0; see the notice for attribution.

The Zephium name and logo are not licensed under the MPL.

Acknowledgements

Zephium stands on Tauri, Wry, Brave's adblock-rust, EasyList and uBlock Origin's uAssets.