The architecture, in public

It is a Chromium browser in an Electron shell

Sureno is a macOS app built on Electron. Every page you open runs in a real Chromium WebContentsView — Blink, V8, site isolation, the renderer sandbox — the same engine Chrome ships. What we wrote is the window around it: tabs, the omnibox, the assistant rail, the start page.

Why not fork Chromium properly?

Because a full chromium/src checkout is tens of gigabytes and hours of compilation per change, and the result would be a version of Chromium's security work maintained by far fewer people. Electron already ships that stack, kept current by people whose job it is. The honest trade is this: the window chrome is ours rather than Chrome's native Views UI, and in exchange the part that faces hostile web pages is the one with a very large team behind it.

Where things run

• Pages — a Chromium view per tab, in the sandbox, in a session isolated from the browser UI.
• Browser UI — our renderer: tabs, omnibox, projects, settings, the assistant rail.
• Private windows — ephemeral Chromium partitions, discarded when the window closes.
• The assistant — a provider you choose. Mock by default, so a fresh install talks to nobody.
• Your data — local app storage. No server, because there is no account.

What is simulated, and labelled as such

Two things in the app demonstrate an interface rather than perform a function, and both say so on screen: the tracker-shield counters and the VPN screen. Neither filters nor tunnels traffic. They are named here so that reading this page is enough to know.

Updates

Packaged builds check an update feed in the background and install on quit. This is how a Chromium security fix reaches you without depending on you noticing a version number. It can be turned off in Settings, and the feed URL is visible there.

If a claim on this site does not match what the app does, that is a bug worth reporting: support@sureno.ai.