Tangent is a browser for people whose work outgrows their tabs. Spaces hold separate tab sets per context. Planning surfaces (Today, Upcoming, Meetings, todos, notes) live beside the web in the same window, on local-first storage, so the day’s structure sits where the day happens. Tab warmth ranks what you actually touch, keeping the browser fast and the sidebar honest. Ads and trackers are blocked at the network layer, with per-site shields.
The engineering bet is chrome ownership. Chromium renders web pages and does nothing else; an anti-corruption layer keeps it isolated behind a single seam. Everything a person touches, about two dozen shell modules covering the sidebar, command palette, omnibox, planning surfaces, settings, context menus, and window chrome, is Tangent’s own. Most webview-based browsers own a toolbar; owning the whole shell is what makes the planning surfaces possible.
The core is system agnostic, with macOS shipping first. Platform-specific code sits behind a compile-time boundary, and the Windows and Linux ports have documented contracts checked against real compile targets. The AI side follows the same philosophy: bring your own agent. Claude Code and Sable already plug into one normalized protocol, tools are hosted over a local MCP bridge, and all of it stays off until you switch it on. Early, and moving fast.