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Mozart

First private beta

v0.1.0-beta.0 is the first release of Mozart — and by far the biggest, since everything ships at once. It's downloaded straight from mozart.build behind a beta access code — no Google Drive, and the auto-updater is live from day one, so every release after this one installs itself. The first public release is reserved for v0.1.0. Expect rough edges: this build exists so the developers who will actually use Mozart can shape it before we open the doors.

Projects & Workspaces

  • Open any local repo as a Project, create one from a fresh folder (Mozart runs git init, registers it, and opens it), or clone from GitHub — paste a URL, or search your account's repos with private/public badges and a live filter when GitHub is connected.
  • Every Project gets an auto-named first Workspace — an isolated, reviewable attempt at a Task.
  • Package manager (npm / pnpm / yarn) is detected and dependencies are installed on first entry.

Projects view — filter, group & state

  • Filter the project list from the header multi-select — show everything, or just the projects you're focused on.
  • Group by Project (default) or Status for a kanban-style view across workspace states.
  • Each Workspace carries a state — Backlog, In Progress, In Review, Done, Canceled — set from the toolbar menu (with a confirm on transitions like reopening a Done workspace).
  • States also advance on their own: the first commit moves a Backlog workspace to In Progress, and opening a PR moves it to In Review.

Threads, Composer & Agent runs

  • Three modes per message — Agent, Plan, Ask — switchable at any point.
  • Up to four Threads per Workspace, each with its own mode, generated title, and unread counter.
  • Model and effort selectors stay visible in the Composer (five effort levels: low / medium / high / xhigh / max).
  • Claude streams straight into the Timeline with tool use, file edits, and shell output rendered live.

Changes, Diff & Git

  • Right aside file tree, live-watched on disk and .gitignore-aware, with A / M / D badges against the base branch.
  • Click any changed file for a clean diff — Git internals stay out of the UI.
  • Edit files in place — a real editor with an Edit/Diff toggle, save or discard, and an unsaved-changes badge.
  • Commit Changes from the aside header (per-file checkboxes, message field) and open draft or ready-for-review PRs directly from Mozart.

Terminal, Run & IDE

  • xterm.js Terminal scoped to each Workspace, persisted across navigation.
  • Per-Project Run command with idle / running / exited(code) / crashed status and output streamed to a read-only panel.
  • Open in IDE auto-detects VS Code, Cursor, Windsurf, Zed, Sublime Text, IntelliJ IDEA, WebStorm, and PyCharm — plus File Manager and Terminal, always available. The last-used one is remembered.

Authentication

  • Sign in via the app.mozart.build web app (Clerk + GitHub or Google), deep-linked back to the desktop via mozart://auth. This web sign-in is the foundation the future cloud Mozart will build on.
  • Tokens live in the system keyring (Keychain / Credential Manager / secret-service) — never in plaintext, never in the local DB.
  • Boots offline once you've signed in, as long as you have at least one local provider configured.

Settings

  • A layered settings.json resolves bundled defaults ◀ global ◀ per-project (/.mozart/settings.json), deep-merged — a missing or malformed layer is skipped, never fatal.
  • Covers theme and color mode, notifications, new-chat agent defaults, and per-project Run/Setup scripts.
  • Edit it from the in-app Settings page or directly on disk.

Onboarding & UI

  • Four-step first-run setup: Git detection, LLM provider, optional GitHub connection, optional product tour. Replay the tour any time from Settings.
  • The mozart theme (warm stone) with light, dark, and system-aware modes.
  • Subtle violet brand accent (#7C3AED); prefers-reduced-motion honored across animations and transitions.

Current limits

  • Invite-only — the download from mozart.build is gated by a beta access code.
  • app.mozart.build handles sign-in only; the cloud companion is not online yet.
  • Claude is the only model provider wired in.
  • Workspace aside width is fixed; no resizable layout, merge UI, conflict resolution, or in-app PR review.
  • Skills (/) and context shortcuts (@) in the Composer are not in this build.