Hoverfly
Lightweight service virtualisation: capture real traffic, then simulate it.
What it is
Hoverfly runs as a proxy that captures real HTTP interactions and replays them as a simulation, with modes for capture, simulate, spy and synthesise, plus middleware for modifying responses and injecting latency. It targets service virtualisation for teams that cannot afford enterprise virtualisation suites.
Best for
Where it is strong
- Capture mode produces a realistic simulation from live traffic with no authoring.
- Latency injection makes it useful for performance and resilience testing too.
- Small footprint — a single Go binary.
Where it falls short
- Smaller community and slower development than WireMock.
- Proxy configuration in complex networks takes effort.
- Captured simulations need periodic refresh.
Pricing
Free and open source
Open sourceFree tier: Everything, self-hosted
What drives the bill: Free and open source. You pay in engineering time and CI minutes.
Check current pricing on SpectoLabs’s siteFigures are indicative and were last reviewed August 2026. Vendors change pricing often; confirm before you commit.
Works with
What people who use Hoverfly say
No reviews of Hoverfly yet. If you have used it in anger, yours would be the first.
Alternatives to Hoverfly
If Hoverfly is not the right fit, these solve the same problem differently.
WireMock
Test Data & Mocks
The standard HTTP mock server for JVM and beyond: record, replay, stub, simulate faults.
Mockoon
Test Data & Mocks
Spin up a realistic mock API from a desktop app in under a minute.
SoapUI / ReadyAPI
API Testing
The long-standing tool for SOAP, JMS and enterprise protocol testing.