Allows importing cURL commands to instantly generate mock API definitions.
Provides tools for mocking GraphQL APIs, including operation-specific matching and response definitions.
Provides a built-in MQTT broker for mocking messaging topics and payloads.
Enables importing Postman collections to automatically create functional mock servers.
Supports importing OpenAPI and Swagger 2.0 specifications to generate mock API structures.
Supports mocking XML-based protocols such as SOAP and defining XML response bodies.
Uses YAML for mock configuration, environment setup, and importing/exporting API definitions.
mockd
One binary. Seven protocols. Zero dependencies.
Mock HTTP, gRPC, GraphQL, WebSocket, MQTT, SSE, and SOAP APIs from a single CLI tool. Import from OpenAPI, Postman, WireMock, HAR, or cURL. Share mocks instantly via built-in cloud tunneling.
Why mockd?
mockd | WireMock | Mockoon | json-server | Prism | MockServer | |
Single binary, no runtime | :white_check_mark: | :x: JVM | :x: Node | :x: Node | :x: Node | :x: JVM |
HTTP mocking | :white_check_mark: | :white_check_mark: | :white_check_mark: | :white_check_mark: | :white_check_mark: | :white_check_mark: |
gRPC mocking | :white_check_mark: | 🔌 Ext | :x: | :x: | :x: | :white_check_mark: |
GraphQL mocking | :white_check_mark: | 🔌 Ext | :x: | :x: | :x: | :x: |
WebSocket mocking | :white_check_mark: | 🔌 Ext | :x: | :x: | :x: | :x: |
MQTT broker | :white_check_mark: | :x: | :x: | :x: | :x: | :x: |
SOAP mocking | :white_check_mark: | :x: | :x: | :x: | :x: | :white_check_mark: |
SSE streaming | :white_check_mark: | :x: | :x: | :x: | :x: | :x: |
OAuth/OIDC provider | :white_check_mark: | :x: | :x: | :x: | :x: | :x: |
Chaos engineering | :white_check_mark: | :white_check_mark: | :x: | :x: | :x: | :x: |
Stateful CRUD | :white_check_mark: | :x: | :white_check_mark: | :white_check_mark: | :x: | :x: |
Cloud tunnel sharing | :white_check_mark: | :x: | :white_check_mark: | :x: | :x: | :x: |
Proxy recording & replay | :white_check_mark: | :white_check_mark: | :white_check_mark: | :x: | :x: | :white_check_mark: |
Import OpenAPI/Postman/HAR | :white_check_mark: | :white_check_mark: | :white_check_mark: | :x: | :white_check_mark: | :white_check_mark: |
Built-in web dashboard | :white_check_mark: | :x: | :white_check_mark: | :x: | :x: | :x: |
MCP server (AI-native) | :white_check_mark: | :x: | :x: | :x: | :x: | :x: |
🔌 Ext = available via separate extension JAR, not bundled with WireMock core. mockd includes all protocols natively in a single binary.
Install
# Quick install
curl -sSL https://get.mockd.io | sh
# Homebrew
brew install getmockd/tap/mockd
# Docker
docker run -p 4280:4280 -p 4290:4290 ghcr.io/getmockd/mockd:latest
# Go
go install github.com/getmockd/mockd/cmd/mockd@latestPre-built binaries for Linux, macOS, and Windows are available on the Releases page.
Quick Start
# Start the mock server
mockd start
# Mock an HTTP endpoint
mockd add http --path /api/users --body '[{"id": 1, "name": "Alice"}]'
# Test it
curl http://localhost:4280/api/users
# → [{"id": 1, "name": "Alice"}]
# Mock a GraphQL API
mockd add graphql --path /graphql --operation users \
--response '[{"id": 1, "name": "Alice"}]'
# Mock a gRPC service
mockd add grpc --proto ./service.proto \
--service myapp.UserService --rpc-method GetUser \
--response '{"id": 1, "name": "Alice"}'
# Mock a WebSocket endpoint
mockd add websocket --path /ws/chat --echo
# Import from OpenAPI, Postman, or cURL
mockd import openapi.yaml
mockd import collection.json
mockd import "curl -X GET https://api.example.com/users"Features
Multi-Protocol Mocking
Mock seven protocols from a single tool with a unified CLI and Admin API:
Protocol | Port | Example |
HTTP/HTTPS | 4280 |
|
gRPC | 50051 |
|
GraphQL | 4280 |
|
WebSocket | 4280 |
|
MQTT | 1883 |
|
SSE | 4280 |
|
SOAP | 4280 |
|
Import & Export
Bring your existing API definitions — no rewriting needed:
mockd import openapi.yaml # OpenAPI 3.x / Swagger 2.0
mockd import collection.json # Postman collections
mockd import recording.har # HAR files
mockd import wiremock-mapping.json # WireMock stubs
mockd import service.wsdl # WSDL → SOAP mocks
mockd import "curl -X GET https://api.example.com/users" # cURL commands
mockd export --format yaml > mocks.yamlCloud Tunnel
Share local mocks with your team instantly. All protocols routed through a single QUIC connection on port 443:
mockd tunnel enable
# → https://a1b2c3d4.tunnel.mockd.io → http://localhost:4280Chaos Engineering
Test how your app handles failures:
# Apply a built-in chaos profile at startup
mockd serve --chaos-profile flaky --config mockd.yaml
# Or enable chaos at runtime
mockd chaos apply slow-apiStateful Mocking
Simulate CRUD resources with automatic ID generation, pagination, and persistence. State is shared across protocols — REST and SOAP operate on the same data:
# mockd.yaml
statefulResources:
- name: users
basePath: /api/users
seedData:
- { id: "1", name: "Alice", email: "alice@example.com" }
mocks:
- type: soap
soap:
path: /soap/UserService
operations:
GetUser:
statefulResource: users # Same data as REST!
statefulAction: getmockd serve --config mockd.yaml
# Create via REST
curl -X POST http://localhost:4280/api/users \
-d '{"name": "Bob"}' -H 'Content-Type: application/json'
# Retrieve via SOAP — same user!
curl -X POST http://localhost:4280/soap/UserService \
-H 'SOAPAction: GetUser' -H 'Content-Type: text/xml' \
-d '<soap:Envelope>...<GetUser><Id>...</Id></GetUser>...</soap:Envelope>'Proxy Recording
Record real API traffic and replay it as mocks:
mockd proxy start --port 8888
# Configure your app to use http://localhost:8888 as proxy
# Traffic is recorded, then replay with:
mockd import recordings/session-name.jsonAdmin API
Full REST API for dynamic mock management at runtime:
# Create a mock
curl -X POST http://localhost:4290/mocks \
-H "Content-Type: application/json" \
-d '{"type":"http","http":{"matcher":{"method":"GET","path":"/health"},"response":{"statusCode":200,"body":"{\"status\":\"ok\"}"}}}'
# List mocks
curl http://localhost:4290/mocks
# Import OpenAPI spec
curl -X POST http://localhost:4290/import \
-H "Content-Type: application/x-yaml" \
--data-binary @openapi.yamlWeb Dashboard
Release builds include a built-in web UI served from the admin port:
mockd start
# Open http://localhost:4290 in your browserManage mocks for all 7 protocols visually with a VS Code-style tabbed editor, command palette (Ctrl+K), mock tree with search/sort/folders, request log viewer with near-miss debugging, and more. Docker images and all release packages include the dashboard automatically.
AI Mock Generation (MCP)
mockd includes a built-in Model Context Protocol server with 18 tools for full mock lifecycle management from AI-powered editors (Cursor, Windsurf, Claude Code):
mockd mcp # Start the MCP server (stdio transport)Tools cover mock CRUD, import/export, chaos engineering (10 built-in profiles), mock verification, stateful resource management, custom operations, and multi-environment context switching.
Configuration
Configure via flags, environment variables, or config files:
# .mockdrc.yaml
port: 4280
adminPort: 4290
httpsPort: 5280
maxLogEntries: 1000Variable | Description | Default |
| Mock server port |
|
| Admin API port |
|
| HTTPS port (0=disabled) |
|
| Config file path |
Documentation
mockd.io — Full documentation, guides, and API reference.
Contributing
See CONTRIBUTING.md for development setup and guidelines.