Some of the most widely used web server frameworks in Rust are:

**Actix-web**: This is a fast and powerful framework that is based on the actor model. It supports async IO, middleware, routing, URL parameter parsing, JSON, WebSocket, HTTP/2, and more. It also has a rich ecosystem of crates that provide authentication, database integration, templating, and more.
**Rocket**: This is a full-stack framework that aims to provide a simple and intuitive API. It supports declarative routing, request guards, data validation, JSON, templating, testing, and more. It also has a built-in code generation tool that reduces boilerplate code. However, it requires nightly Rust to work.
**Tide**: This is a minimal and composable framework that is built on top of async-std. It supports middleware, routing, state management, error handling, JSON, WebSocket, and more. It also has a modular design that allows you to use different components as needed.
**Warp**: This is a fast and lightweight framework that is built on top of hyper. It supports filters, middleware, routing, URL parameter parsing, JSON, WebSocket, SSE, and more. It also has a functional style that allows you to compose different filters into endpoints.
**Gotham**: This is a flexible and stable framework that is built on top of hyper and tokio. It supports middleware, routing, URL parameter parsing, JSON, testing, and more. It also has a strong focus on concurrency and performance.
**Axum**: This is a new and experimental framework that is built on top of hyper and tower. It supports async/await syntax, middleware, routing, URL parameter parsing, JSON, WebSocket, SSE, and more. It also has a similar API to warp but with more flexibility.
**Dropshot**: This is a framework that is designed for building REST APIs. It supports OpenAPI specification, JSON schema validation, pagination, authentication, testing, and more. It also has a declarative approach that allows you to define your endpoints using macros.

These are some of the web server frameworks in Rust that you can use for your projects. They have different strengths and weaknesses depending on your needs and preferences. You can find more information about them on their respective websites or documentation pages. I hope this helps you choose the best framework for your web development needs.
spam fails_task lang_mismatch pii not_appropriate hate_speech sexual_content quality toxicity humor helpfulness creativity violence