Hoverfly vs Testcontainers

Free and open source

Free tier available

Free and open source. You pay in engineering time and CI minutes.

Free. Testcontainers Cloud, which offloads container execution, is a paid Docker product.

Everything, self-hosted

The libraries are free and open source.

Emerging

SpectoLabs · since 2016

Category standard

AtomicJar (Docker) · since 2015

• 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.

• Tests run against the real database engine, so dialect and behaviour differences surface early.
• Containers are disposable, which removes shared-state flakiness entirely.
• Excellent language coverage with idiomatic APIs.

• Smaller community and slower development than WireMock.
• Proxy configuration in complex networks takes effort.
• Captured simulations need periodic refresh.

• Requires a Docker daemon in CI, which not every environment provides.
• Container startup adds seconds to each test run unless reused carefully.
• Heavier resource usage than in-memory alternatives.

Teams needing lightweight service virtualisation against real recorded traffic.

Integration tests that currently use in-memory databases and lie to you.