Open-source alternative to ReadyAPI Virtualization

Which virtualization capabilities map to Microcks and WireMock

This table maps the main ReadyAPI virtualization capabilities to Microcks and WireMock and flags where the supplied facts stop short of a clear answer. Use the check and cross marks as a starting point, then confirm each unclear row against the current project documentation before you commit to a design.

Microcks or WireMock: which self-hosted mock fits which team

Running Microcks or WireMock alongside the rest of ReadyAPI

Most teams do not switch every ReadyAPI module at once. The decisions below cover which functional tests keep calling virtual endpoints, which SOAP suites point at Microcks, and where data-driven runs move to CI. Each one determines how much of the existing suite survives the move.

How to migrate virtual services without breaking test suites

This sequence moves each ReadyAPI virtual service to a self-hosted mock only after its replacement answers the same way the original did, so test suites keep passing and rollback stays possible at every stage.

1. Inventory every virtual service and its source

   List each ReadyAPI virtual service, the SoapUI project or WSDL it was built from, any OpenAPI definitions behind it, and the test suites that call it. Record the owning team, the environments that depend on it and whether it is used in CI. Confirm this list with the teams that run the suites, because mocks often serve tests nobody remembers writing. The step is done when every service has one row with its source file, its consumers and its environments.

2. Choose Microcks or WireMock for each service

   Decide per service. Microcks suits teams that already hold OpenAPI, AsyncAPI, gRPC, GraphQL, Postman collections or SoapUI projects and want contract tests alongside mocks. WireMock suits HTTP stubbing driven by code or configuration files, especially inside Java test suites. Some services may need both, for example a mock for a unit test and a contract check in a shared environment. Record the choice and the reason in the inventory. Confirm that each candidate supports the protocol the service actually uses, since SOAP and message-based interfaces may need different handling.

3. Import definitions into the chosen mock tool

   Load the SoapUI project, WSDL, OpenAPI or other definition into Microcks, or create WireMock mappings from the same contract. Start from the source your team already maintains, not from a copy of the ReadyAPI mock. Check that every operation and resource in the inventory appears in the new tool. The output is a mock that exposes the same endpoints, and a short list of anything the import did not carry over, such as scripted logic or custom response rules that need manual rebuilding.

4. Reproduce success, error and edge responses

   Compare the ReadyAPI virtual service with its replacement for each operation. Capture the status codes, headers, response bodies and timing that consumers depend on, including faults, timeouts, empty results and validation errors. Rebuild each case in the new tool and record a pass or fail for each one. Ask a consumer team to review any response they parse field by field. The step is done when the replacement matches the original for every case in the list.

5. Run both mocks in parallel and compare test results

   Point a copy of the test suite at the new mock while the ReadyAPI virtual service keeps serving the original runs. Compare pass and fail results, logs and any assertion that depends on response detail, and investigate every difference before accepting it. Keep the ReadyAPI service available for this whole period. The check is complete when results match across the agreed runs and no difference is left unexplained. The length of this period is a decision for your team, not a fixed figure.

6. Wire mocks into CI and shared test environments

   Start the replacement mocks from your CI pipeline, either as containers or as processes, and point test jobs at them through configuration rather than hard-coded addresses. Store mock definitions in version control so changes go through review. For shared environments, decide who owns each mock and how updates are rolled out. The output is a pipeline run that starts the mocks, executes the suites and reports results without any ReadyAPI component. Confirm that the pipeline can run without network access to a commercial licence server if that matters to your environment.

7. Retire ReadyAPI virtual services with a rollback path

   Once the parallel results match and CI runs are stable, switch each consumer to the new mock and keep the ReadyAPI definition archived, not deleted, for a period your change process sets. Define a rollback step for each service that repoints the suite to the ReadyAPI virtual service, and test that step once before retiring anything. Remove the service only after the owner signs off that no consumer still depends on it. The sequence is complete when every inventoried service has a named replacement, a tested rollback and a documented owner.

What running self-hosted mocks on Kubernetes requires

Questions teams ask before replacing ReadyAPI Virtualization

Where the open-source mock approach falls short

Decision steps before you cancel the virtualization module

This sequence turns a renewal question into evidence: which virtual services your teams depend on, whether each one can be rebuilt from a specification or SoapUI source, and whether one of them runs in your CI pipeline before you decide. The output is a renewal decision based on tested services, not on assumptions about the module.

1. Inventory every active virtual service

   Ask the test owners and the team that administers ReadyAPI to list each virtual service the module hosts, the consumers that call it, the environments it runs in, and who relies on it for regression or integration tests. Include services that run only on a scheduled job or on a shared test server, since they are easy to miss. The step is done when the list has one owner and one consumer group per service, and the team agrees the list is complete.

2. Confirm each service has a usable source

   For every service on the inventory, check whether a maintained OpenAPI, AsyncAPI or gRPC (protobuf) definition exists, or whether the behavior is captured in a SoapUI project or a Postman collection that Microcks can import. Mark services that exist only as hand-built virtual responses inside ReadyAPI, since those need to be rebuilt as stubs. The step is done when each service is labeled with its source type and the services without a source are listed as a separate rebuild task.

3. Choose one representative service for the proof of concept

   Select a service that is used often, has a clear specification, and has a stable set of consumer tests, so that a pass or fail tells you something about the migration. Avoid services with complex stateful logic as the first candidate. Record the request and response examples that the consumers expect, because they become the acceptance criteria. The step is done when the team has one service, its specification and a written list of expected responses.

4. Load the service into Microcks or WireMock

   Import the specification into Microcks, which accepts OpenAPI, AsyncAPI, gRPC, GraphQL schemas, Postman collections and SoapUI projects, or define the same behavior as WireMock stubs if the team prefers code-based HTTP stubbing. Run it in a test environment you control and check every expected response from the previous step against the mock. The step is done when the mock returns the expected responses and any gap is logged with its cause.

5. Run the consumer tests against the mock in CI

   Point the existing consumer tests at the self-hosted mock and run them from your continuous integration pipeline, not from a developer workstation, so the result is repeatable and visible to the pipeline owners. Keep the same test assertions as before, and record how long setup takes and which files or secrets the job needs. The step is done when the pipeline shows the same pass and fail results as the ReadyAPI run for that service, with any differences explained.

6. Document the gaps and the rebuild effort

   Write down which ReadyAPI virtualization features the proof of concept did not need or could not reproduce, such as custom scripting, stateful sequences or data-driven responses, and estimate the rebuild work for the remaining services from the inventory. Include who maintains the mock definitions after handover and where they are stored. The step is done when the team has a short gap register and a rebuild list it can review with the budget holder.

7. Set the renewal decision with the evidence

   Bring the inventory, the source review, the proof of concept results and the gap register to the renewal discussion. Ask SmartBear for a quote that lists the virtualization module separately from the functional and performance modules, so you can see what you would stop paying for. Decide whether to cancel, reduce scope or renew for a defined period. The step is done when the decision is recorded with the evidence attached and the migration owner is named.