# Express vs FastAPI

| Attribute | Express | FastAPI |
|---|---|---|
| **Vioscale score** | 77.1 (79% (high)) | 73 (78% (high)) |
| activity.commits_last_30d | 40 | 210 |
| adoption.dependent_repos | 1,853,938 | 43,608 |
| adoption.github_stars | 69,394 | 101,862 |
| adoption.package_downloads_weekly | 131,895,868 | 127,838,650 |
| adoption.stackoverflow_questions | 96,000 | 31,000 |
| content.faq | `[{"answer":"Express is a minimalist web framework for Node.js that provides core routing and middleware capabilities for building web applications and APIs. It is written in JavaScript and runs on the Node.js runtime environment, requiring Node.js 18 or higher for use.","source":"https://expressjs.com","question":"What is Express and what programming language does it use?","confidence":0.95},{"answer":"Yes, Express is open source software maintained by the OpenJS Foundation and released under the MIT license, a permissive open source license that permits commercial and private use. The project is publicly available on GitHub as expressjs/express and receives community contributions.","source":"https://github.com/expressjs/express","question":"Is Express open source and what is its license?","confidence":0.95},{"answer":"Express enables developers to define HTTP routing (GET, POST, PUT, DELETE, etc.), handle requests through middleware functions, serve static files, render dynamic templates, handle errors, and connect to databases. It provides these features through a thin, extensible layer over Node.js without imposing a specific architecture.","source":"https://expressjs.com/en/starter/basic-routing.html","question":"What are the core capabilities of Express?","confidence":0.95},{"answer":"Express uses middleware functions to process HTTP requests in a pipeline. Middleware are functions that have access to the request and response objects, allowing developers to execute code, modify requests/responses, end the request cycle, or pass control to the next middleware function.","source":"https://expressjs.com","question":"How does Express handle requests and what is middleware?","confidence":0.93},{"answer":"Express is explicitly unopinionated and minimalist, providing only fundamental web application features and leaving architectural decisions to developers. This differs from more opinionated frameworks that provide a complete structure and predetermined patterns for application organization.","source":"https://expressjs.com","question":"What makes Express different from other Node.js frameworks?","confidence":0.92},{"answer":"Yes, Express can be used with TypeScript by installing type definitions via npm (@types/express and @types/node), and developers can run TypeScript files directly with recent versions of Node.js (22.18.0 or higher) without requiring a separate build step.","source":"https://expressjs.com/en/starter/installing.html","question":"Can Express be used with TypeScript?","confidence":0.94},{"answer":"Express is well-suited for building REST APIs, full-featured web applications, mobile app backends, and microservices running on Node.js. Its lightweight nature makes it effective for projects requiring quick setup and customization without imposed patterns.","source":"https://expressjs.com","question":"What types of projects is Express suitable for?","confidence":0.93}]` | `[{"answer":"FastAPI is a modern Python framework for building REST APIs and web services. It is built on top of Starlette for web functionality and Pydantic for data validation, combining these components with Python type hints to enable automatic API documentation, data validation, and fast development cycles.","source":"https://fastapi.tiangolo.com","question":"What is FastAPI and what is it primarily used for?","confidence":0.95},{"answer":"FastAPI is a Python framework that relies on Starlette for HTTP handling and async support, and Pydantic for data validation and serialization. It leverages Python's native type hints as a central feature to drive both validation and automatic interactive API documentation generation.","source":"https://fastapi.tiangolo.com","question":"What programming language is FastAPI built on and what are its core dependencies?","confidence":0.95},{"answer":"FastAPI is completely open source and free, distributed under the MIT license with no cost to use or modify. The creators offer an optional commercial service called FastAPI Cloud for managed deployment and hosting, but the core framework incurs no licensing fees.","source":"https://fastapi.tiangolo.com","question":"Is FastAPI open source and what is its pricing model?","confidence":0.95},{"answer":"FastAPI is one of the fastest Python web frameworks, with benchmarks showing performance on par with Node.js and Go-based APIs. This speed stems from its async/await capabilities and reliance on highly optimized underlying libraries like Starlette and Pydantic.","source":"https://fastapi.tiangolo.com","question":"How does FastAPI's performance compare to other Python web frameworks?","confidence":0.92},{"answer":"Uvicorn is the standard ASGI server for FastAPI, run via the fastapi run command or uvicorn CLI. Deployment typically involves running Uvicorn with multiple worker processes for concurrency, containerizing with Docker for cloud platforms, or using managed services that automatically handle scaling and reverse proxying.","source":"https://fastapi.tiangolo.com/deployment/concepts/","question":"What ASGI server should I use to deploy FastAPI, and what are the typical deployment models?","confidence":0.93},{"answer":"FastAPI has built-in support for WebSockets enabling real-time bidirectional communication, Server-Sent Events for server-to-client streaming, and background tasks for asynchronous processing. All of these features are natively integrated without requiring additional extensions.","source":"https://fastapi.tiangolo.com/advanced/","question":"Does FastAPI support real-time communication and asynchronous patterns?","confidence":0.94},{"answer":"FastAPI includes built-in support for OAuth2 with JSON Web Tokens (JWT), HTTP Basic Authentication, password hashing utilities, bearer token validation, and Cross-Origin Resource Sharing (CORS) configuration. These security patterns are designed to be straightforward to implement for common use cases.","source":"https://fastapi.tiangolo.com/advanced/","question":"What authentication and security capabilities does FastAPI provide out of the box?","confidence":0.93},{"answer":"FastAPI integrates with SQL relational databases via standard ORMs, supports form data and file uploads, includes middleware patterns, and can mount alongside WSGI applications like Flask or Django. It also provides Jinja2 template support, dependency injection for complex patterns, and auto-generation of client SDKs from your API.","source":"https://fastapi.tiangolo.com/advanced/","question":"What common integrations and databases does FastAPI support?","confidence":0.92}]` |
| deployment.options | `{"cloud":true,"on_prem":true,"self_hosted":true}` | `{"cloud":true,"self_hosted":true}` |
| description.long | A minimal framework providing essential routing, middleware, and HTTP utilities for building web applications and APIs in Node.js without imposing architectural constraints. | FastAPI is a modern web framework for constructing APIs in Python that combines high performance with developer convenience through automatic validation, interactive documentation generation, and first-class type hint support. |
| features.capabilities | `{"language":"JavaScript","api_routes":true,"hot_reload":false,"edge_runtime":false,"file_routing":false,"streaming_ssr":false,"typescript_first":false,"server_components":false}` | `{"language":"Python","api_routes":true,"hot_reload":true}` |
| integrations.count | 13 | 11 |
| integrations.list | `[{"name":"Cassandra"},{"name":"Couchbase"},{"name":"CouchDB"},{"name":"LevelDB"},{"name":"MySQL"},{"name":"MongoDB"},{"name":"Neo4j"},{"name":"Oracle"},{"name":"PostgreSQL"},{"name":"Redis"},{"name":"SQL Server"},{"name":"SQLite"},{"name":"Elasticsearch"}]` | `[{"name":"Starlette"},{"name":"Pydantic"},{"name":"OpenAPI"},{"name":"JSON Schema"},{"name":"Swagger UI"},{"name":"ReDoc"},{"name":"OAuth2"},{"name":"JWT"},{"name":"HTTP Basic authentication"},{"name":"Cookies"},{"name":"Session management"}]` |
| language.primary | JavaScript | Python |
| license.spdx | MIT | MIT |
| market.availability | `{"source":"https://expressjs.com","hqCountry":"US","confidence":0.95,"primaryMarkets":["US"],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` | `{"source":"https://fastapi.tiangolo.com","hqCountry":"ES","confidence":0.95,"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` |
| platform.support | `{"cli":true,"web":true}` | `{"cli":true,"web":true}` |
| pricing | `{"type":"open_source","freeTier":true,"sourceUrl":"https://expressjs.com","retrievedAt":"2026-08-14T10:20:13.635Z"}` | `{"type":"open_source","freeTier":true,"sourceUrl":"https://fastapi.tiangolo.com","retrievedAt":"2026-08-14T11:09:42.452Z"}` |
| pricing.free_tier | yes | yes |
| pricing.model | commercial | commercial |
| pricing.price_level | free | free |
| pricing.transparent | yes | - |
| release.cadence_days | 4 | 14 |
| release.history | `[{"url":"https://github.com/expressjs/express/releases/tag/v4.22.2","date":"2026-05-11T18:54:02Z","type":"stable","version":"v4.22.2"},{"url":"https://github.com/expressjs/express/releases/tag/v5.2.1","date":"2025-12-01T20:54:44Z","type":"stable","version":"v5.2.1"},{"url":"https://github.com/expressjs/express/releases/tag/v5.2.0","date":"2025-12-01T16:21:03Z","type":"stable","version":"v5.2.0"},{"url":"https://github.com/expressjs/express/releases/tag/v4.22.1","date":"2025-12-01T20:55:45Z","type":"stable","version":"v4.22.1"},{"url":"https://github.com/expressjs/express/releases/tag/4.22.0","date":"2025-12-01T16:19:48Z","type":"stable","version":"4.22.0"},{"url":"https://github.com/expressjs/express/releases/tag/v5.0.1","date":"2024-10-08T19:41:00Z","type":"stable","version":"v5.0.1"},{"url":"https://github.com/expressjs/express/releases/tag/v5.1.0","date":"2025-03-31T14:04:44Z","type":"stable","version":"v5.1.0"},{"url":"https://github.com/expressjs/express/releases/tag/4.21.2","date":"2024-12-05T22:41:41Z","type":"stable","version":"4.21.2"},{"url":"https://github.com/expressjs/express/releases/tag/4.21.1","date":"2024-10-08T18:38:48Z","type":"stable","version":"4.21.1"},{"url":"https://github.com/expressjs/express/releases/tag/4.21.0","date":"2024-09-11T22:34:26Z","type":"stable","version":"4.21.0"},{"url":"https://github.com/expressjs/express/releases/tag/v5.0.0","date":"2024-09-10T04:51:37Z","type":"stable","version":"v5.0.0"},{"url":"https://github.com/expressjs/express/releases/tag/4.20.0","date":"2024-09-10T02:06:04Z","type":"stable","version":"4.20.0"},{"url":"https://github.com/expressjs/express/releases/tag/v5.0.0-beta.3","date":"2024-03-25T14:59:35Z","type":"prerelease","version":"v5.0.0-beta.3"},{"url":"https://github.com/expressjs/express/releases/tag/4.19.2","date":"2024-03-25T14:32:36Z","type":"stable","version":"4.19.2"},{"url":"https://github.com/expressjs/express/releases/tag/5.0.0-beta.2","date":"2024-03-25T14:59:09Z","type":"prerelease","version":"5.0.0-beta.2"},{"url":"https://github.com/expressjs/express/releases/tag/4.19.1","date":"2024-03-25T14:31:15Z","type":"stable","version":"4.19.1"},{"url":"https://github.com/expressjs/express/releases/tag/4.19.0","date":"2024-03-20T16:43:00Z","type":"stable","version":"4.19.0"},{"url":"https://github.com/expressjs/express/releases/tag/4.18.3","date":"2024-02-29T11:44:48Z","type":"stable","version":"4.18.3"},{"url":"https://github.com/expressjs/express/releases/tag/4.18.2","date":"2022-10-08T20:12:36Z","type":"stable","version":"4.18.2"},{"url":"https://github.com/expressjs/express/releases/tag/4.18.1","date":"2022-04-29T19:32:52Z","type":"stable","version":"4.18.1"}]` | `[{"url":"https://github.com/fastapi/fastapi/releases/tag/0.141.1","date":"2026-07-29T17:17:26Z","type":"stable","version":"0.141.1"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.141.0","date":"2026-07-29T14:47:36Z","type":"stable","version":"0.141.0"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.13","date":"2026-07-28T15:36:47Z","type":"stable","version":"0.140.13"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.12","date":"2026-07-28T15:04:48Z","type":"stable","version":"0.140.12"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.11","date":"2026-07-28T14:33:49Z","type":"stable","version":"0.140.11"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.10","date":"2026-07-28T14:21:00Z","type":"stable","version":"0.140.10"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.9","date":"2026-07-28T12:38:03Z","type":"stable","version":"0.140.9"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.8","date":"2026-07-28T10:31:04Z","type":"stable","version":"0.140.8"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.7","date":"2026-07-27T17:33:02Z","type":"stable","version":"0.140.7"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.6","date":"2026-07-27T16:31:22Z","type":"stable","version":"0.140.6"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.5","date":"2026-07-27T16:02:33Z","type":"stable","version":"0.140.5"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.4","date":"2026-07-27T15:46:29Z","type":"stable","version":"0.140.4"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.3","date":"2026-07-27T15:29:52Z","type":"stable","version":"0.140.3"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.2","date":"2026-07-27T14:14:50Z","type":"stable","version":"0.140.2"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.1","date":"2026-07-27T12:07:15Z","type":"stable","version":"0.140.1"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.0","date":"2026-07-24T21:16:20Z","type":"stable","version":"0.140.0"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.139.2","date":"2026-07-16T15:05:47Z","type":"stable","version":"0.139.2"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.139.1","date":"2026-07-16T09:18:15Z","type":"stable","version":"0.139.1"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.139.0","date":"2026-07-01T16:35:19Z","type":"stable","version":"0.139.0"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.138.2","date":"2026-06-29T12:43:58Z","type":"stable","version":"0.138.2"}]` |
| reliability.status_page | - | yes |
| security.disclosure_policy | yes | - |
| security.scorecard | 8.9 | - |
| security.vulnerabilities | `{"count":6,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=npm&package_name=express&per_page=100","last_12m":1,"max_severity":"MODERATE"}` | `{"count":2,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=pypi&package_name=fastapi&per_page=100","last_12m":0,"max_severity":"HIGH"}` |

## Capabilities (Web Frameworks)

| Capability | Express | FastAPI |
|---|:--:|:--:|
| **Core** |  |  |
| Rendering model | - | - |
| File-based routing | ✗ | - |
| Language | JavaScript | Python |
| **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 2026-09-01T17:19:22.164Z. "-" = undocumented, not absent.*