Zorvik
Zorvik --> From HTTP to MCP: test, mock, load-test every API, free and local.
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>log in to commentHi everyone! I built Zorvik because testing APIs had started to feel like signing up for a SaaS: an account just to send a GET request, features behind a paywall, my collections synced to someone else's cloud. I wanted one fast desktop app that does all of it, for free, with my files staying mine. --------------------------------------------------------------- --------------------------------------------------------------- What's inside: - An API client for HTTP (1.1, 2 and 3), GraphQL with subscriptions, gRPC, WebSocket, Socket.IO, SSE, MQTT, TCP, UDP and DNS - MCP testing: connect to the MCP servers your AI agents use, call their tools, and set up your own MCP servers without writing code - Mock servers from your requests or an OpenAPI file, with delays and faults when you want to break things on purpose - Load tests with virtual users or a fixed request rate, ramps and pass/fail thresholds - A collection runner and a zorvik command line for CI, with JUnit reports - Your Postman collections and scripts come along (pm.*, lodash, chai, moment and more), plus OpenAPI, Swagger and cURL import - Code export in 16 languages and 170 dynamic variables for test data - Your coding agent (Claude Code, Cursor and others) can drive the whole app over MCP - A Training Bootcamp with hands-on labs if you're new to any of this --------------------------------------------------------------- --------------------------------------------------------------- The promises: every feature is free, there's no account, no cloud sync, and nothing is collected. Workspaces are plain YAML files in a folder you pick, so you share them through Git like code. It's built in Rust, runs on Windows, macOS and Linux, and it's open source (MIT or Apache-2.0). --------------------------------------------------------------- --------------------------------------------------------------- I'd love your feedback: what's the one thing your current API tool gets wrong? Tell me here or open an issue on GitHub. And if Zorvik saves you some time, a star helps a lot. --------------------------------------------------------------- --------------------------------------------------------------- Download: https://github.com/LibreGuild/zorvik/releases/latest Website: https://libreguild.github.io/zorvik/
Zorvik is a free, open-source desktop app to build, test, mock and load-test APIs across many protocols locally.
- for
- Developers and QA engineers needing offline, multi-protocol API tooling
- pricing
- free
- license
- Apache-2.0
- v0.2.0Zorvik 0.2.013 days ago
- v0.1.2Zorvik 0.1.213 days ago
- nightlyZorvik nightly (build 47)11 days ago
Key features
- Multi-protocol support — Handles HTTP/1-3, GraphQL, gRPC, WebSocket, Socket.IO, SSE, MQTT, TCP, UDP and DNS in one app.
- Mock server & routes — Create mock endpoints with params, delays, faults, CORS and forwarding.
- Load testing — Run virtual-user or arrival-rate load tests with configurable thresholds.
- MCP testing for AI agents — Test and mock MCP servers that AI agents use, with schema validation.
- Plain-file workspaces — All requests and configs are stored as readable YAML files in Git-friendly folders.
- CLI for CI/CD — Command-line tools (zorvik run, load, serve, mcp) integrate with pipelines and generate JUnit reports.
- Network inspector tools — Built-in TLS inspector, DNS lookup, port check, ping and encoders for Base64, JWT, hashes.
- Built-in learning bootcamp — Interactive lessons and labs teach API concepts and testing within the app.
Use cases
- Mock third-party APIs locally for integration testing
- Run load tests on a development machine before staging
- Validate MCP tool responses for AI agents in CI pipelines
- Create version-controlled API collections stored as YAML
- Teach new team members API testing with the built-in bootcamp
Zorvik vs alternatives
| Best for | All-in-one offline API workbench | Offline-first API client | Open-source API client | API platform with collaboration |
|---|---|---|---|---|
| Pricing | Free | Free | Free | Subscription |
| DevHunt upvotes | 5 | 0 | 0 | 0 |
| Launched | Oct 2026 | — | — | — |
- Zorvik vs Bruno: Bruno is also offline-first and Git-friendly but focuses on a single protocol per workspace, whereas Zorvik unifies many protocols in one app.
- Zorvik vs Insomnia: Insomnia supports REST, GraphQL and gRPC with a GUI, but lacks the built-in load testing and MCP features of Zorvik.
- Zorvik vs Postman: Postman offers cloud sync, collaboration and a paid tier; Zorvik is fully local, free and open source with broader protocol coverage.
Zorvik FAQ
Do I need an account or internet connection to use Zorvik?+
No. Zorvik is local-first, works offline, and does not require any sign-in or cloud sync.
Is Zorvik open source?+
Yes, it is released under MIT or Apache-2.0 licenses by the LibreGuild community.
Can I run Zorvik in CI pipelines?+
Yes, the CLI commands (zorvik run, load, serve, mcp) work on headless machines and can output JUnit or JSON reports.
How are my secrets stored?+
Secret values, cookies and tokens stay on your computer and are never written to shared files or sent elsewhere.
What file format does Zorvik use for collections?+
Requests and environments are stored as plain YAML files in a folder you own, making them Git-compatible.
Does Zorvik support testing AI agent tools?+
Yes, it includes MCP server support to test and mock the tools and schemas that AI agents consume.
Summarized by DevHunt from libreguild.github.io · Oct 2, 2026. Details may change; check the official site.