# Fastify vs Ktor

| Attribute | Fastify | Ktor |
|---|---|---|
| **Vioscale score** | 63.9 (78% (high)) | 60.8 (49% (low)) |
| activity.commits_last_30d | 69 | 57 |
| adoption.dependent_repos | 16,712 | 1,171 |
| adoption.github_stars | 37,024 | 14,503 |
| deployment.options | `{"self_hosted":true}` | - |
| description.long | A Node.js web framework optimized to handle high request volumes with minimal overhead, featuring a plugin system, JSON Schema validation, and native TypeScript support. | Ktor is an open-source framework for creating asynchronous server and client applications, from microservices to HTTP clients. Built on Kotlin and coroutines, it emphasizes simplicity, lightweight design, and extensibility. |
| features.capabilities | `{"language":"JavaScript/TypeScript","api_routes":true,"typescript_first":true}` | `{"language":"Kotlin"}` |
| integrations.count | 17 | - |
| integrations.list | `[{"name":"Next.js"},{"name":"Apollo Server"},{"name":"Angular"},{"name":"PostgreSQL"},{"name":"MongoDB"},{"name":"Redis"},{"name":"Elasticsearch"},{"name":"Swagger/OpenAPI"},{"name":"WebSocket"},{"name":"JWT"},{"name":"Helmet"},{"name":"Sentry"},{"name":"RabbitMQ"},{"name":"CORS"},{"name":"CSRF"},{"name":"OAuth2"},{"name":"Kubernetes"}]` | - |
| language.primary | JavaScript | Kotlin |
| license.spdx | MIT | Apache-2.0 |
| pricing | `{"type":"open_source","freeTier":true,"sourceUrl":"https://fastify.dev","retrievedAt":"2026-08-16T21:34:26.497Z"}` | `{"type":"open_source","freeTier":true,"sourceUrl":"https://ktor.io/","retrievedAt":"2026-08-13T23:07:06.179Z"}` |
| pricing.free_tier | yes | yes |
| pricing.model | commercial | open_source |
| pricing.price_level | free | free |
| release.cadence_days | 3 | 27 |
| release.history | `[{"url":"https://github.com/fastify/fastify/releases/tag/v6.0.0-alpha.2","date":"2026-08-19T01:54:36Z","type":"prerelease","version":"v6.0.0-alpha.2"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.12.1","date":"2026-08-18T19:51:41Z","type":"stable","version":"v5.12.1"},{"url":"https://github.com/fastify/fastify/releases/tag/v6.0.0-alpha.1","date":"2026-08-13T15:57:10Z","type":"prerelease","version":"v6.0.0-alpha.1"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.12.0","date":"2026-08-13T15:55:21Z","type":"stable","version":"v5.12.0"},{"url":"https://github.com/fastify/fastify/releases/tag/v6.0.0-alpha.0","date":"2026-08-11T08:32:37Z","type":"prerelease","version":"v6.0.0-alpha.0"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.11.3","date":"2026-08-08T06:55:46Z","type":"stable","version":"v5.11.3"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.11.2","date":"2026-08-03T08:21:47Z","type":"stable","version":"v5.11.2"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.11.1","date":"2026-08-03T08:10:10Z","type":"stable","version":"v5.11.1"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.11.0","date":"2026-07-30T09:32:16Z","type":"stable","version":"v5.11.0"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.10.0","date":"2026-07-05T09:37:06Z","type":"stable","version":"v5.10.0"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.9.0","date":"2026-06-28T08:21:36Z","type":"stable","version":"v5.9.0"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.8.5","date":"2026-04-14T12:09:02Z","type":"stable","version":"v5.8.5"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.8.4","date":"2026-03-23T10:31:20Z","type":"stable","version":"v5.8.4"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.8.3","date":"2026-03-23T10:20:21Z","type":"stable","version":"v5.8.3"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.8.2","date":"2026-03-07T09:42:46Z","type":"stable","version":"v5.8.2"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.8.1","date":"2026-03-05T10:10:57Z","type":"stable","version":"v5.8.1"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.8.0","date":"2026-03-05T09:33:05Z","type":"stable","version":"v5.8.0"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.7.4","date":"2026-02-02T18:23:39Z","type":"stable","version":"v5.7.4"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.7.3","date":"2026-02-02T17:57:52Z","type":"stable","version":"v5.7.3"},{"url":"https://github.com/fastify/fastify/releases/tag/v5.7.2","date":"2026-01-26T11:15:54Z","type":"stable","version":"v5.7.2"}]` | `[{"url":"https://github.com/ktorio/ktor/releases/tag/3.5.2","date":"2026-08-04T12:08:07Z","type":"stable","version":"3.5.2"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.5.1","date":"2026-06-29T08:05:31Z","type":"stable","version":"3.5.1"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.5.0","date":"2026-05-18T06:57:48Z","type":"stable","version":"3.5.0"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.4.3","date":"2026-04-23T11:20:32Z","type":"stable","version":"3.4.3"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.4.2","date":"2026-03-30T13:37:19Z","type":"stable","version":"3.4.2"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.4.1","date":"2026-03-04T14:20:52Z","type":"stable","version":"3.4.1"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.4.0","date":"2026-01-23T08:55:39Z","type":"stable","version":"3.4.0"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.3.3","date":"2025-11-27T12:13:53Z","type":"stable","version":"3.3.3"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.3.2","date":"2025-11-05T14:08:06Z","type":"stable","version":"3.3.2"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.3.1","date":"2025-10-10T06:19:56Z","type":"stable","version":"3.3.1"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.3.0","date":"2025-09-12T11:59:39Z","type":"stable","version":"3.3.0"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.2.3","date":"2025-07-29T14:18:09Z","type":"stable","version":"3.2.3"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.2.2","date":"2025-07-14T11:45:21Z","type":"stable","version":"3.2.2"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.2.1","date":"2025-07-04T08:57:57Z","type":"stable","version":"3.2.1"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.2.0","date":"2025-06-13T12:19:28Z","type":"stable","version":"3.2.0"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.1.3","date":"2025-05-06T11:52:28Z","type":"stable","version":"3.1.3"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.1.2","date":"2025-03-28T09:27:52Z","type":"stable","version":"3.1.2"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.1.1","date":"2025-02-25T11:49:42Z","type":"stable","version":"3.1.1"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.1.0","date":"2025-02-12T11:44:49Z","type":"stable","version":"3.1.0"},{"url":"https://github.com/ktorio/ktor/releases/tag/3.0.3","date":"2024-12-19T14:25:41Z","type":"stable","version":"3.0.3"}]` |
| security.scorecard | 8.3 | 4.6 |
| security.vulnerabilities | `{"count":10,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=npm&package_name=fastify&per_page=100","last_12m":5,"max_severity":"HIGH"}` | `{"count":1,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=maven&package_name=io.ktor%3Aktor-client-cio&per_page=100","last_12m":0,"max_severity":"LOW"}` |

## Capabilities (Web Frameworks)

| Capability | Fastify | Ktor |
|---|:--:|:--:|
| **Core** |  |  |
| Rendering model | - | - |
| File-based routing | - | - |
| Language | JavaScript/TypeScript | Kotlin |
| **Rendering** |  |  |
| Server components | - | - |
| Streaming SSR | - | - |
| **Fullstack** |  |  |
| Built-in API / backend routes | ✓ | - |
| **DX** |  |  |
| First-class TypeScript | ✓ | - |
| Fast refresh / HMR | - | - |
| **Deployment** |  |  |
| Edge runtime support | - | - |

*Source: Vioscale. Generated 2026-09-01T17:08:54.054Z. "-" = undocumented, not absent.*