# Mock Service Worker (MSW) vs Prism

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

| Attribute | Mock Service Worker (MSW) | Prism |
|---|---|---|
| **vioscaleAI score** | 60.5 (79% (high)) | 49.6 (17% (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":"Open-source toolkit for generating realistic mock HTTP servers from API specifications and validating API contracts It is indexed under API Mocking.","source":"https://stoplight.io/open-source/prism","question":"What is Prism?","confidence":0.6},{"answer":"Prism is open source, so it can be self-hosted and used at no licence cost. A commercial or hosted edition starts at $11 per user per month. Prices are published openly on the vendor's own pricing page. Pricing changes often, so verify at source before relying on it.","source":"https://stoplight.io/pricing","question":"Is Prism free to use?","confidence":0.6},{"answer":"Prism supports a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://stoplight.io/open-source/prism","question":"What platforms does Prism support?","confidence":0.6},{"answer":"Yes. Prism can be deployed cloud / SaaS and self-hosted, so it does not have to run on the vendor's infrastructure.","source":"https://stoplight.io/open-source/prism","question":"Can Prism be self-hosted?","confidence":0.6},{"answer":"We have confirmed 9 integrations for Prism, including GitHub, GitLab, Azure DevOps, Bitbucket, LDAP, SAML SSO, Google Analytics and OpenAPI, plus 1 more. This is what we could verify from public sources, so the vendor may support others we have not indexed.","source":"https://stoplight.io/open-source/prism","question":"What does Prism integrate with?","confidence":0.6},{"answer":"We have independently confirmed GDPR for Prism. Certifications we do not list are ones we have not been able to verify from public sources, which is not the same as Prism not holding them. Always confirm compliance directly before you rely on it.","source":"https://stoplight.io/security-practices","question":"What security certifications does Prism have?","confidence":0.7}]` |
| deployment.options | - | `{"cloud":true,"self_hosted":true}` |
| 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. | Stoplight is a design-first API platform that enables teams to collaboratively design APIs, generate interactive documentation, and create mock API servers with built-in validation. It supports multiple API standards including OpenAPI, AsyncAPI, and Arazzo. |
| 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":"cli_binary","open_source":true,"mocking_mode":"dynamic_templating","pricing_model":"open_source","market_segment":"dev-tool","openapi_import":true,"ci_cd_integration":true,"proxy_passthrough":true,"collaboration_sharing":true}` |
| integrations.count | 8 | 1 |
| 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":"GitHub"},{"name":"GitLab"},{"name":"Azure DevOps"},{"name":"Bitbucket"},{"name":"LDAP"},{"name":"SAML SSO"},{"name":"Google Analytics"},{"name":"OpenAPI","native":true},{"name":"Postman","native":true}]` |
| language.primary | TypeScript | - |
| license.spdx | MIT | - |
| market.availability | `{"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` | `{"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"}` | `{"type":"hybrid","plans":[{"free":true,"name":"Free","summary":"Free, open-source","features":["API editor","OpenAPI/JSON schema visual designer","Code-based editing","Local mock servers","API console","Technical knowledge base","24x7 knowledge base access"],"minSeats":1,"components":[{"kind":"fixed","amount":0,"period":"month","currency":"USD"}],"description":"Open-source, self-hosted version","contactSales":false,"includedLimits":{"users":"1","projects":"1"}},{"free":false,"name":"Basic","summary":"$44/month (annually) or $56/month; includes 3 users, $11 per additional user","features":["OpenAPI/JSON schema visual designer","Interactive docs","Instant mock servers","Code-based editing","Schema reuse","Design validation","Git sync","OpenAPI export","Automatic mock servers","Request validation","Configurable response codes"],"minSeats":3,"commitment":"annual","components":[{"kind":"fixed","amount":44,"period":"month","currency":"USD"},{"kind":"per_unit","unit":"seat","amount":11,"period":"month","currency":"USD"}],"description":"Design an API as an individual","contactSales":false,"includedLimits":{"users":"3","projects":"Unlimited"}},{"free":false,"name":"Startup","summary":"$113/month (annually) or $147/month; includes 8 users, $11 per additional user","features":["All Basic features","Private projects","Multi-branch support","Custom domains, theming and favicon","Google Analytics integration","Approved email domains","Automatic changelogs","Dependency graph"],"minSeats":8,"commitment":"annual","components":[{"kind":"fixed","amount":113,"period":"month","currency":"USD"},{"kind":"per_unit","unit":"seat","amount":11,"period":"month","currency":"USD"}],"description":"Build an API program for small teams","contactSales":false,"includedLimits":{"users":"8","projects":"Unlimited"}},{"free":false,"name":"Pro Team","summary":"$362/month (annually) or $453/month; includes 15 users, $22 per additional user","features":["All Startup features","Shared style guides","Workspace groups","Remove Stoplight branding","Self-hosted Git providers","Activity logs","LDAP & SAML SSO","Component Libraries","User management and RBAC","Per-project user access","Workspace teams"],"minSeats":15,"commitment":"annual","components":[{"kind":"fixed","amount":362,"period":"month","currency":"USD"},{"kind":"per_unit","unit":"seat","amount":22,"period":"month","currency":"USD"}],"description":"Govern APIs across your organization","contactSales":false,"includedLimits":{"teams":"20","users":"15","projects":"Unlimited"}},{"free":false,"name":"Enterprise","summary":"Custom pricing","features":["All Pro Team features","Custom payment terms","Invoicing","Priority support"],"commitment":"annual","description":"Your API program at scale","contactSales":true,"includedLimits":{"teams":"Unlimited","users":"Unlimited","projects":"Unlimited"}}],"summary":"Free open-source version. Stoplight SaaS: from $44/month (Basic). Free 14-day trial.","currency":"USD","freeTier":true,"sourceUrl":"https://stoplight.io/pricing","retrievedAt":"2026-08-17T21:32:12.868Z","freeTrialDays":14,"startingPrice":{"amount":11,"period":"month","currency":"USD"},"billingPeriods":["month","year"]}` |
| pricing.free_tier | yes | yes |
| pricing.model | open_source | open_source |
| pricing.price_level | free | free |
| pricing.transparent | yes | 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.gdpr | - | yes |
| 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) | Prism |
|---|:--:|:--:|
| **Capabilities** |  |  |
| Mocking mode | Dynamic templating | Dynamic templating |
| Stateful scenarios | ✓ | - |
| Fault chaos injection | - | - |
| Openapi import | ✓ | ✓ |
| Proxy passthrough | - | ✓ |
| Admin API | - | - |
| Deployment | Embedded library | CLI binary |
| Legacy protocol virtualization | - | - |
| Collaboration sharing | - | ✓ |
| Ci cd integration | ✓ | ✓ |
| Open source | ✓ | ✓ |
| Market segment | Dev tool | Dev tool |
| Pricing model | Open source | Open source |

*Source: vioscaleAI. Generated 2026-10-16T00:20:28.530Z. "-" = undocumented, not absent.*