Introduction

Victauri — Verified Introspection & Control for Tauri Applications.

Victauri is full-stack testing for Tauri apps. Click a button in the frontend, verify the Rust command ran, confirm the database row was written — from a single test, on macOS, Windows, and Linux, in CI. Unlike browser automation tools like Playwright — which can’t even attach to a Tauri webview on macOS or Linux — Victauri runs inside the app process with simultaneous access to the webview DOM, the IPC layer, the Rust backend, the database, and native window state (the database and backend introspection tools — query_db, app_state, app_info, memory/process stats — are read-only; invoke_command can deliberately call mutating commands, exactly like the frontend).

It works by embedding a lightweight server inside your Tauri app’s own process — debug builds only; the server is gated behind #[cfg(debug_assertions)], so init() is a no-op and nothing listens in release. Your test suite, curl, or CI talks to it over a plain REST/HTTP API. No WebDriver, no Selenium grid, no browser dependency.

And because that same server also speaks the Model Context Protocol (MCP), any AI agent — Claude Code, Cursor, Windsurf — gets the exact same full-stack access for interactive debugging. Testing is the job; the agent integration is the bonus.

Who Is This For?

• Tauri app developers who want real full-stack tests (frontend → IPC → Rust → database) instead of frontend mocks that lie about the backend
• QA and CI engineers who need cross-platform end-to-end tests without standing up a WebDriver/Selenium grid or paying for macOS runners
• AI agent developers who need to drive, debug, or inspect a running Tauri application over MCP

Key Value Proposition

One plugin, one line of code, full-stack access:

All of this is exposed two ways from the same server: a plain REST/HTTP API (POST /api/tools/{name}) that your test suite, shell scripts, and CI call directly — no handshake, no session — and the Model Context Protocol (MCP) for AI agents. Write deterministic tests against REST; connect Claude Code, Cursor, or any MCP client when you want an agent to drive the app interactively.

Design Principles

1. Same-process — The MCP server runs inside the Tauri app process, not as a separate sidecar. This gives sub-millisecond tool response times and direct AppHandle access.

2. Zero runtime cost in release — The server is gated behind #[cfg(debug_assertions)], so init() is a no-op and nothing listens in release builds. (The crate still compiles in as a dependency; add it as a dev-dependency if you want it absent from the release binary entirely.)

3. Full-stack — WebView + IPC + Backend + DB, not just DOM. Cross-boundary verification catches state drift between frontend and backend.

4. MCP-native — Speaks the protocol AI agents already understand. No custom SDKs or adapters needed.

5. Cross-platform — Works identically on Windows, macOS, and Linux. No CDP dependency.

6. Plugin, not framework — One line in Cargo.toml to add, one line to remove. Your app architecture stays unchanged.

Project Structure

Victauri is a Rust workspace with 7 crates:

victauri/
├── crates/
│   ├── victauri-cli/        # CLI: init, check, test, record, watch, coverage
│   ├── victauri-core/       # Shared types: events, registry, snapshots
│   ├── victauri-macros/     # Proc macros: #[inspectable]
│   ├── victauri-plugin/     # Tauri plugin: embedded MCP server + JS bridge
│   ├── victauri-test/       # Test client + assertion helpers
│   └── victauri-watchdog/   # Crash-recovery health monitor
├── editors/
│   └── vscode/              # VS Code extension
└── examples/
    └── demo-app/            # Reference Tauri app with full test suite

Current Status

All 7 crates are published to crates.io. In a one-time deep evaluation (May 2026) against 5 real-world open-source Tauri apps (Kanri, En Croissant, Surrealist, Duckling, Lettura), 867 of 895 checks passed (96.9%) with zero Victauri bugs and zero changes required to the apps — the remaining failures were test-script issues or correct actionability enforcement. A reproducible per-release compatibility harness (scripts/compat) now re-verifies against these apps automatically; it currently confirms Kanri at 15/15 on the latest release, while the other four have drifted upstream and don’t yet build in the harness (re-pin pending). Supports Tauri 2.0+ with rmcp 1.5.0.

Victauri is open source (Apache-2.0) and built by 4DA Systems, which uses it to test its own Tauri app. Adopters and contributors are very welcome — see Contributing, and if you ship a Tauri app we’d love to hear how it goes.