# Mock Service Worker (MSW) vs Parasoft Virtualize

**Leader by vioscaleAI score:** Mock Service Worker (MSW)

| Attribute | Mock Service Worker (MSW) | Parasoft Virtualize |
|---|---|---|
| **vioscaleAI score** | 60.5 (79% (high)) | 50.4 (19% (low)) |
| activity.commits_last_30d | 15 | - |
| adoption.dependent_repos | 11,851 | - |
| adoption.github_stars | 18,290 | - |
| content.faq | `[{"answer":"An API mocking library that intercepts network requests at the browser and Node.js levels, allowing consistent mock responses across testing frameworks, tools, and applications without requiring client-specific stubs or configuration. It is indexed under API Mocking.","source":"https://mswjs.io","question":"What is Mock Service Worker (MSW)?","confidence":0.6},{"answer":"Mock Service Worker (MSW) is open source, so it can be self-hosted and used at no licence cost. It is released under the MIT licence. Pricing changes often, so verify at source before relying on it.","source":"https://mswjs.io","question":"Is Mock Service Worker (MSW) free to use?","confidence":0.6},{"answer":"Mock Service Worker (MSW) supports the web and a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://mswjs.io","question":"What platforms does Mock Service Worker (MSW) support?","confidence":0.6},{"answer":"We have confirmed 8 integrations for Mock Service Worker (MSW), including Vitest, Playwright, Storybook, React Native, Express, fetch, axios and react-query. This is what we could verify from public sources, so the vendor may support others we have not indexed.","source":"https://mswjs.io","question":"What does Mock Service Worker (MSW) integrate with?","confidence":0.6},{"answer":"Yes. Mock Service Worker (MSW) is published under the MIT licence, a permissive licence that generally allows commercial use and modification. Licence terms can change between releases, so verify against the repository for the version you intend to use.","source":"https://github.com/mswjs/msw","question":"Is Mock Service Worker (MSW) open source?","confidence":0.95}]` | `[{"answer":"A codeless tool that creates virtual versions of APIs and services for testing across 120+ protocols and message formats, with AI-powered mock generation and stateful simulation capabilities It is indexed under API Mocking.","source":"https://www.parasoft.com/products/parasoft-virtualize/","question":"What is Parasoft Virtualize?","confidence":0.6},{"answer":"We have confirmed browser-based access to Parasoft Virtualize. That is the extent of what we could verify from public sources, so it may well offer desktop or mobile clients we have not indexed.","source":"https://www.parasoft.com/products/parasoft-virtualize/","question":"What platforms does Parasoft Virtualize support?","confidence":0.6},{"answer":"We have confirmed 11 integrations for Parasoft Virtualize, including REST, SOAP, JMS, MQ, JDBC, Kafka, gRPC and Jenkins, plus 3 more. This is what we could verify from public sources, so the vendor may support others we have not indexed.","source":"https://www.parasoft.com/products/parasoft-virtualize/","question":"What does Parasoft Virtualize integrate with?","confidence":0.6},{"answer":"Parasoft Virtualize is available worldwide. The vendor is headquartered in the United States.","source":"https://www.parasoft.com/products/parasoft-selenic/plans-pricing/","question":"Where is Parasoft Virtualize available?","confidence":0.75}]` |
| description.long | An open-source API mocking library that uses the Service Worker API to intercept network requests in browsers and Node.js, enabling developers to mock REST, GraphQL, and WebSocket APIs for testing and development without modifying application code. | Parasoft Virtualize provides a codeless platform for creating simulated API and service dependencies across 120+ protocols. Teams can generate lightweight API mocks or stateful virtual services for testing, with direct integration into CI/CD pipelines and support for AI-driven workflows. |
| features.capabilities | `{"deployment":"embedded_library","open_source":true,"mocking_mode":"dynamic_templating","pricing_model":"open_source","market_segment":"dev-tool","openapi_import":true,"ci_cd_integration":true,"stateful_scenarios":true}` | `{"deployment":"browser","mocking_mode":"dynamic_templating","market_segment":"dev-tool","ci_cd_integration":true,"proxy_passthrough":true,"stateful_scenarios":true,"fault_chaos_injection":true,"legacy_protocol_virtualization":true}` |
| integrations.count | 8 | 11 |
| integrations.list | `[{"name":"Vitest"},{"name":"Playwright"},{"name":"Storybook"},{"name":"React Native"},{"name":"Express"},{"name":"fetch"},{"name":"axios"},{"name":"react-query"},{"name":"Hono","native":true},{"name":"Fastify","native":true}]` | `[{"name":"REST"},{"name":"SOAP"},{"name":"JMS"},{"name":"MQ"},{"name":"JDBC"},{"name":"Kafka"},{"name":"gRPC"},{"name":"Jenkins"},{"name":"Azure DevOps"},{"name":"TeamCity"},{"name":"Bamboo"}]` |
| language.primary | TypeScript | - |
| license.spdx | MIT | - |
| market.availability | `{"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` | `{"hqCountry":"US","primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` |
| platform.support | `{"cli":true,"web":true}` | `{"web":true}` |
| pricing | `{"type":"open_source","summary":"Free and open source","freeTier":true,"sourceUrl":"https://mswjs.io","retrievedAt":"2026-10-14T21:33:51.343Z"}` | - |
| pricing.free_tier | yes | - |
| pricing.model | open_source | commercial |
| pricing.price_level | free | - |
| pricing.transparent | yes | - |
| release.cadence_days | 2 | - |
| release.history | `[{"url":"https://github.com/mswjs/msw/releases/tag/v3.0.3","date":"2026-10-10T01:37:25Z","type":"stable","version":"v3.0.3"},{"url":"https://github.com/mswjs/msw/releases/tag/v3.0.2","date":"2026-10-03T01:30:56Z","type":"stable","version":"v3.0.2"},{"url":"https://github.com/mswjs/msw/releases/tag/v3.0.1","date":"2026-09-30T12:36:57Z","type":"stable","version":"v3.0.1"},{"url":"https://github.com/mswjs/msw/releases/tag/v3.0.0","date":"2026-09-28T15:40:54Z","type":"stable","version":"v3.0.0"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.15.0","date":"2026-07-08T01:43:13Z","type":"stable","version":"v2.15.0"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.14.7","date":"2026-07-07T18:24:49Z","type":"stable","version":"v2.14.7"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.14.6","date":"2026-05-11T09:41:54Z","type":"stable","version":"v2.14.6"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.14.5","date":"2026-05-08T01:51:55Z","type":"stable","version":"v2.14.5"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.14.4","date":"2026-05-07T12:26:03Z","type":"stable","version":"v2.14.4"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.14.3","date":"2026-05-04T17:14:11Z","type":"stable","version":"v2.14.3"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.14.2","date":"2026-04-29T15:37:39Z","type":"stable","version":"v2.14.2"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.14.1","date":"2026-04-29T15:11:07Z","type":"stable","version":"v2.14.1"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.14.0","date":"2026-04-29T14:12:53Z","type":"stable","version":"v2.14.0"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.13.6","date":"2026-04-24T15:53:44Z","type":"stable","version":"v2.13.6"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.13.5","date":"2026-04-23T01:46:05Z","type":"stable","version":"v2.13.5"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.13.4","date":"2026-04-16T16:25:47Z","type":"stable","version":"v2.13.4"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.13.3","date":"2026-04-14T01:44:10Z","type":"stable","version":"v2.13.3"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.13.2","date":"2026-04-08T11:18:18Z","type":"stable","version":"v2.13.2"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.13.1","date":"2026-04-07T18:14:15Z","type":"stable","version":"v2.13.1"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.13.0","date":"2026-04-06T12:37:48Z","type":"stable","version":"v2.13.0"}]` | - |
| security.scorecard | 6.2 | - |
| security.trust_center | - | https://www.parasoft.com/blog/iso-pas-8800-compliance/ |
| security.vulnerabilities | `{"count":0,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=npm&package_name=msw&per_page=100","last_12m":0,"max_severity":null}` | - |

## Capabilities (API Mocking)

| Capability | Mock Service Worker (MSW) | Parasoft Virtualize |
|---|:--:|:--:|
| **Capabilities** |  |  |
| Mocking mode | Dynamic templating | Dynamic templating |
| Stateful scenarios | ✓ | ✓ |
| Fault chaos injection | - | ✓ |
| Openapi import | ✓ | - |
| Proxy passthrough | - | ✓ |
| Admin API | - | - |
| Deployment | Embedded library | Browser |
| Legacy protocol virtualization | - | ✓ |
| Collaboration sharing | - | - |
| Ci cd integration | ✓ | ✓ |
| Open source | ✓ | - |
| Market segment | Dev tool | Dev tool |
| Pricing model | Open source | - |

*Source: vioscaleAI. Generated 2026-10-16T20:03:00.961Z. "-" = undocumented, not absent.*