MockServer vs WireMock

MockServer is a free, self-hosted tool for mocking and proxying HTTP, HTTPS, and gRPC services during isolated testing. It can verify requests as well as stand in for services. Teams can generate mocks and validate traffic against OpenAPI or Swagger contracts, or import recorded sessions from browser HAR files and Postman collections. Beyond HTTP services, it can mock gRPC, AsyncAPI brokers such as Kafka, MQTT, and AMQP, and OAuth2/OIDC providers. Its protocol coverage includes HTTP/1.1, HTTP/2, HTTPS, SOCKS, and experimental HTTP/3, which uses a separate UDP port. For fault-oriented testing, it can add latency, errors, dropped connections, and malformed responses to mocked or proxied traffic. Deployment options include Docker, an executable JAR, Helm/Kubernetes, Testcontainers, Homebrew, and a JVM-less bundle. A web dashboard displays logs, expectations, and recorded traffic; Prometheus metrics and OpenTelemetry tracing are available for shared environments. Each instance includes an MCP server at /mockserver/mcp. The /mockserver/status and /mockserver/ready probes remain reachable without authentication or authorization.

WireMock Cloud provides simulated API environments for software development, testing and AI coding workflows. It supports REST, GraphQL, gRPC, Kafka and SOAP, and can import mocks from Postman, HAR files, OpenAPI or Swagger, and WireMock open source. WireMock Runner can record APIs, including internal services behind a corporate firewall, then run simulations locally or in CI/CD. A remote MCP server and Agent Skills work with named clients including Claude Code, OpenAI Codex, GitHub Copilot, Cursor, VS Code and Augment. The free plan costs nothing and allows one user, three mock APIs, 1,000 calls/month and 10 requests per second, with a limited CLI for local recording. Mocks stop when the monthly call quota is exceeded and resume at the next billing-cycle reset. Enterprise pricing is by tailored quote and includes unlimited calls and team members subject to the license agreement, statefulness, AI features, hybrid deployment, priority support and an SLA. WireMock Cloud is built on the open-source WireMock API mocking platform.