Hoverfly vs Neosync

Free and open source

From $20 per user/month (indicative, cloud)

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

Self-hosting is free; the cloud service is priced per user and record volume.

Everything, self-hosted

Open-source self-hosted edition is free.

Emerging

SpectoLabs · since 2016

Emerging

Nucleus Cloud · since 2023

• 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.

• Open source and self-hostable, so sensitive data never leaves your infrastructure.
• Preserves referential integrity across tables.
• Far cheaper than the commercial data-privacy platforms.

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

• Young project with a small community.
• Fewer database connectors than the incumbents.
• Self-hosting is operational work.

Teams needing lightweight service virtualisation against real recorded traffic.

Teams that need anonymised test data but cannot justify enterprise pricing.