# Mock Service Worker (MSW) vs Parasoft Virtualize

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

| Attribute | Mock Service Worker (MSW) | Parasoft Virtualize |
|---|---|---|
| **Vioscale score** | 58.1 (81% (high)) | 31 (8% (low)) |
| adoption.dependent_repos | 11,851 | - |
| adoption.github_stars | 18,168 | - |
| description.long | 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. | Virtualize enables teams to mock unavailable or incomplete dependencies, allowing continuous testing without waiting for external services. The platform supports over 120 protocols and message formats, including REST, SOAP, JMS, MQ, and Kafka, with capabilities for stateful interactions and complex workflows. It integrates with CI/CD pipelines and LLM-based AI workflows. |
| 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":"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}` | - |
| pricing | `{"type":"open_source","freeTier":true,"sourceUrl":"https://mswjs.io","retrievedAt":"2026-08-17T21:32:17.412Z"}` | - |
| pricing.free_tier | yes | - |
| pricing.model | commercial | commercial |
| pricing.price_level | free | - |
| release.cadence_days | 2 | - |
| release.history | `[{"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"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.12.14","date":"2026-03-21T01:42:04Z","type":"stable","version":"v2.12.14"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.12.13","date":"2026-03-17T11:36:51Z","type":"stable","version":"v2.12.13"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.12.12","date":"2026-03-17T01:42:36Z","type":"stable","version":"v2.12.12"},{"url":"https://github.com/mswjs/msw/releases/tag/v2.12.11","date":"2026-03-15T19:07:45Z","type":"stable","version":"v2.12.11"}]` | - |
| security.scorecard | 6.2 | - |
| 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 | - | - |
| Stateful scenarios | - | - |
| Fault chaos injection | - | - |
| Openapi import | - | - |
| Proxy passthrough | - | - |
| Admin API | - | - |
| Deployment | - | - |
| Legacy protocol virtualization | - | - |
| Collaboration sharing | - | - |
| Ci cd integration | - | - |
| Open source | - | - |
| Market segment | - | - |
| Pricing model | - | - |

*Source: Vioscale. Generated 2026-09-01T17:11:07.702Z. "-" = undocumented, not absent.*