A cross-platform API client
in ~10 MB
One installer, ready to run. Requests, mock server, automated testing and load testing built in — no bundled browser engine, no Node sandbox, no JRE.
One installer, ready to run. Requests, mock server, automated testing and load testing built in — no bundled browser engine, no Node sandbox, no JRE.
20–40× lighter than Electron-based tools for the same workload.
Rust LTO + a single-process model + zero-copy SQLite storage.
8 HTTP methods, 6 body types; paste-to-import cURL; {{name}} variables resolved everywhere; per-tab drafts.
API Key / Basic / Bearer / OAuth2 (all four flows); values encrypted with AES-256-GCM; cookie replay + global proxy.
Local axum mock with port auto-probing, fully offline; rules first, template variables for dynamic responses, hot-reload and fault injection.
JSON test scripts + multi-case drawer: variable injection, extraction, assertions; load tests chart QPS and P50/P90/P99.
System / dark / light themes; configurable request timeout; auto-increment sequences; multi-project tabs keep drafts.
Dedicated debugging view: Query / Variables / OperationName, with data and errors rendered per GraphQL semantics.
WebSocket send/receive / Ping / auto-reconnect plus SSE subscribe and frame parsing, in a pop-out window.
Environment import/export (native / Postman); OpenAPI 3.1 auto-normalized on import; Rust / PHP snippets importable too.
OpenAPI 3.x / Swagger 2.0 / Postman v2.1 interop; Markdown docs; client code in cURL / JavaScript / Java / Go / Rust / Python / PHP with syntax highlighting.
Built-in MCP server and local HTTP control plane: save a cURL or a Java method as an endpoint with one sentence.
Numbers from official installers and local measurements — verify yourself.
| Dimension | RustFox | Postman | Bruno | Insomnia |
|---|---|---|---|---|
| Installer size | ~10 MB (system WebView) | ~310 MB (Electron) | ~433 MB (Electron) | ~200 MB (Electron) |
| Cold start | < 1 s | 2–4 s | 2–5 s | 2–4 s |
| Runtime memory | ~40 MB | 500 MB+ | 300 MB+ | 200 MB+ |
| App shell | System WebView | Chromium + Node.js | Chromium + Node.js | Chromium + Node.js |
The app starts a loopback control plane on launch — save a cURL or backend snippet as an endpoint with one sentence. Full guide: Agent integration.
Configure the bundled rustfox-mcp absolute path once in Claude Code / Cursor and get four tools: save_curl / list_projects / list_endpoints / agent_info.
Any HTTP-capable tool can call the 127.0.0.1:4110 control plane: POST /agent/curl to import, GET /agent/projects, /agent/endpoints, /agent/health to query.
Loopback-only binding; random UUID token (0600); import is the only write op; existing base_url values are never overwritten.
Dark / light / follow-system themes.
More in the user guide FAQ.
It isn't — that's Gatekeeper blocking an un-notarized app. Move it to Applications, run xattr -cr /Applications/RustFox.app, then right-click → Open.
Click "More info → Run anyway". The installer has no code-signing certificate yet — normal for open-source apps.
The data-dir master.key was lost. Restore from a backup JSON (Settings → Restore).
The binary isn't on PATH. Since v0.0.10 use the absolute path inside the install bundle (see the agent section above), not a bare rustfox-mcp.
Expected: dev builds use the isolated RustFox-dev directory. Move data via backup JSON.
The top-bar "Feedback" button generates a local diagnostics report — attach it to a GitHub Issue.
Grab the latest build from GitHub Releases; in-app updates supported.
macOS says "damaged"? Run xattr -cr /Applications/RustFox.app then right-click → Open. See the user guide.
Bilingual docs, versioned with the repository.