Lightweight service virtualisation: capture real traffic, then simulate it.
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
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.
No reviews of Hoverfly yet. If you have used it in anger, yours would be the first.
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