Mockd vs Prism
Full-featured API mocking beyond OpenAPI validation
Feature Comparison
Side-by-side comparison of Mockd and Prism capabilities.
| Feature | Mockd | Prism |
|---|---|---|
| Language / Runtime | Go (single binary) | Node.js (npm install) |
| Protocols | 7 (HTTP, WS, GraphQL, gRPC, MQTT, SSE, SOAP) | HTTP only |
| OpenAPI Support | Import to generate mocks | Native (spec-driven) |
| Request Matching | Path, headers, body, JSONPath, regex, mTLS | Path + method only |
| Response Templating | Go templates, Faker, dynamic values | Static examples from spec |
| Stateful Mocking | Yes | No |
| Proxy / Record | Yes | Proxy with validation |
| WebSocket | Native | No |
| gRPC | Native | No |
| GraphQL | Native | No |
| Dependencies | None | Node.js 18+ |
| Memory (idle) | <30MB | ~80MB+ |
| Built-in Cloud Tunnel | Yes | No |
| MCP Server (AI editors) | 18 tools | No |
| AI Mock Generation | 4 providers | No |
Why Switch from Prism?
No Node.js Required
Mockd is a single Go binary. No npm install, no node_modules, no Node.js version management. Download one file and run.
7 Protocols, Not Just HTTP
Prism only mocks HTTP APIs. Mockd handles WebSocket, gRPC, GraphQL, MQTT, SSE, and SOAP — all from one binary with one config format.
Real Request Matching
Prism routes requests based on the OpenAPI path. Mockd matches on headers, query params, body content, JSONPath expressions, regex patterns, and even mTLS client identity.
Dynamic Response Templates
Prism returns static examples from your OpenAPI spec. Mockd uses Go templates with Faker data, timestamps, request echoing, and conditional logic for realistic dynamic responses.
Stateful Scenarios
Simulate real API workflows: create a resource, then retrieve it. Mockd supports state machines so sequential calls return different responses. Prism has no state concept.
Works Without a Spec
Prism requires an OpenAPI spec to function. Mockd works with or without one — define mocks in simple YAML, import from OpenAPI, or generate with AI.
When to Use Each Tool
Prism and Mockd solve different problems. Pick the right one.
Prism works well for:
- Complete OpenAPI specs with instant validation
- Strict design-first API development (spec before code)
- HTTP-only mocking with spec-accurate example responses
- Quick OpenAPI validation in existing Node.js toolchains
Choose Mockd when you need:
- More than HTTP — WebSocket, gRPC, MQTT, GraphQL, SSE, SOAP
- Dynamic responses — Faker data, templates, conditional logic
- Advanced matching — Headers, body, JSONPath, regex, mTLS
- Stateful workflows — Create-then-read, state machines
- No spec required — Works with YAML, OpenAPI import, or AI generation
Easy Migration
If you have an OpenAPI spec, run mockd import openapi spec.yaml to auto-generate matching mock definitions. Mockd creates endpoints for every path/method combination with response templates based on your spec's examples and schemas. For anything Prism couldn't do — WebSocket connections, stateful flows, advanced matching — add those directly to the generated YAML config.
Ready to Switch?
Get started with Mockd in under a minute. Single binary, no dependencies.
curl -sSL https://get.mockd.io | sh