Open Source Crystal Web Development Frameworks

Amber makes building web applications fast, simple, and enjoyable. Get started with blazing-fast performance. Amber provides the bare metal performance of the Crystal Language. It provides productivity and happiness through a powerful CLI and familiar design patterns seen in Kemal, Rails, Phoenix and other popular frameworks. Use code generation and scaffolding features to rapidly build prototypes. Amber is licensed under the MIT license, which makes it perfect for use in commercial applications. Instead of having to plan where things go, Amber comes with a set of conventions to guide you in developing your application. Tools are built-in to prevent and mitigate common attacks against web applications. Minimize the risk of SQL injection, form tampering, cross-site request forgery, and several other attacks. Crystal is a type safe, compiled language inspired by the simplicity of Ruby.

Lucky is a web framework written in Crystal. It helps you work quickly, catch bugs at compile time, and deliver blazing-fast responses. Lucky is extremely fast and uses very little memory. You and your users will love the extra dose of speed. Authentication, asset management, CORS, database ORM, and more can all be included when creating a new Lucky project. Instead of finding bugs in QA or in production, Lucky is designed to catch as many bugs as possible at compile time. Lucky uses Action classes for handling HTTP requests and responses. The classes map the routes and parameters it handles to a response block. Lucky can generate these classes for you with ’lucky gen.action`. Using a class per action provides very solid automatic error detection, as well as the generation of routing, path, and link helpers and methods.

Lightning fast, super simple web framework. Support all REST verbs. By default Kemal gzips most files, skipping only very small files, or those which don’t benefit from zipping. Websocket support. Request/Response context, easy parameter handling. Middleware support. Built-in JSON support. Built-in static file serving. Built-in view templating via ECR. Documentation. Before filters are evaluated before each request within the same context as the routes. They can modify the request and response. Since Crystal does not allow using variables in macro literals, you need to generate another helper macro to make the code easier to read and write. You can add many blocks to the same verb/path combination by calling it multiple times they will be called in the same order they were defined. Browser redirects are simple as well. Simply call env.redirect in the route’s corresponding block.

Amethyst is currently undergoing a re-write from the ground up. We'll be releasing the public roadmap soon. Amethyst is a web framework written in the Crystal language. The goals of Amethyst are to be extremely fast and to provide agility in application development, much like Rails.