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.

CI Release License
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Rust + Tauri 2 + system WebView · Windows / macOS / Linux · Apache-2.0

Miyo workspace — request editor with a mock 200 response

Why Miyo?

20–40× lighter than Electron-based tools for the same workload.

~10 MB
Installer size
< 1s
Cold start
~40 MB
Runtime memory
0
Cloud dependencies

Fast, without cutting features

Rust LTO + a single-process model + zero-copy SQLite storage.

🚀

Requests & editing

8 HTTP methods, 6 body types; paste-to-import cURL; {{name}} variables resolved everywhere; per-tab drafts.

🔐

Auth & security

API Key / Basic / Bearer / OAuth2 (all four flows); values encrypted with AES-256-GCM; cookie replay + global proxy.

🧪

Mock server

Local axum mock with port auto-probing, fully offline; rules first, template variables for dynamic responses, hot-reload and fault injection.

✅

Testing & load testing

JSON test scripts + multi-case drawer: variable injection, extraction, assertions; load tests chart QPS and P50/P90/P99.

🎨

Appearance & preferences

System / dark / light themes; configurable request timeout; auto-increment sequences; multi-project tabs keep drafts.

📡

GraphQL workbench

Dedicated debugging view: Query / Variables / OperationName, with data and errors rendered per GraphQL semantics.

⚡

Realtime debugging

WebSocket send/receive / Ping / auto-reconnect plus SSE subscribe and frame parsing, in a pop-out window.

🔁

Environment interop

Environment import/export (native / Postman); OpenAPI 3.1 auto-normalized on import; Rust / PHP snippets importable too.

🔄

Import / export

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.

🤖

AI Agent integration

Built-in MCP server and local HTTP control plane: save a cURL or a Java method as an endpoint with one sentence.

How it compares

Numbers from official installers and local measurements — verify yourself.

DimensionMiyoPostmanBrunoInsomnia
Installer size~10 MB (system WebView)~310 MB (Electron)~433 MB (Electron)~200 MB (Electron)
Cold start< 1 s2–4 s2–5 s2–4 s
Runtime memory~40 MB500 MB+300 MB+200 MB+
App shellSystem WebViewChromium + Node.jsChromium + Node.jsChromium + Node.js

AI Agent integration

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.

🤖

MCP server (recommended)

Configure the bundled miyo-mcp absolute path once in Claude Code / Cursor and get four tools: save_curl / list_projects / list_endpoints / agent_info.

🔌

Direct HTTP

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.

🔒

Local-first security

Loopback-only binding; random UUID token (0600); import is the only write op; existing base_url values are never overwritten.

{ "mcpServers": { "miyo": { "command": "/Applications/Miyo.app/Contents/MacOS/miyo-mcp" } } }

A quick look

Dark / light / follow-system themes.

Miyo dashboard
Dashboard — welcome stats, recent activity, project cards, drag-and-drop import
Miyo workspace
Workspace — request editing / syntax highlighting / mock / testing / load testing
Miyo GraphQL workbench
GraphQL workbench — Query / Variables / OperationName with data vs errors rendered per GraphQL semantics
Miyo realtime debugging
Realtime debugging — WebSocket / SSE frame log with Ping, auto-reconnect and pop-out window

FAQ

More in the user guide FAQ.

macOS says the app is "damaged"?

It isn't — that's Gatekeeper blocking an un-notarized app. Move it to Applications, run xattr -cr /Applications/Miyo.app, then right-click → Open.

Windows SmartScreen warning?

Click "More info → Run anyway". The installer has no code-signing certificate yet — normal for open-source apps.

Environment variables look garbled?

The data-dir master.key was lost. Restore from a backup JSON (Settings → Restore).

MCP reports spawn ENOENT?

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 miyo-mcp.

Dev build can't see release data?

Expected: dev builds use the isolated Miyo-dev directory. Move data via backup JSON.

How do I report a problem?

The top-bar "Feedback" button generates a local diagnostics report — attach it to a GitHub Issue.

Download & install

Grab the latest build from GitHub Releases; in-app updates supported.

macOS says "damaged"? Run xattr -cr /Applications/Miyo.app then right-click → Open. See the user guide.

Documentation

Bilingual docs, versioned with the repository.