What is MIME type "text/x-crystal"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

text/x-crystal is a MIME type used for files that hold source code written in the Crystal programming language. It tells text editors and build tools how to handle the file's content.

Files labeled with this MIME type use a non-standard x- prefix, which signals an experimental or less formally registered format. Their primary use is to enable proper syntax highlighting, code linting, and compilation detection for Crystal source files. They are also useful in web environments where file content must be identified and served correctly.

Enables code editors to apply Crystal syntax highlighting
Helps build tools and compilers detect and process the file correctly
Supports web servers in serving the file as plain text with proper formatting

Such files are typically identified by the extension CR. For more details on the language and its ecosystem, visit the Crystal official website.

Associated file extensions

.cr

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: text/x-crystal

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="text/x-crystal">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');    
    
    http.createServer((req, res) => {    
      res.setHeader('Content-Type', 'text/x-crystal');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.cr

FAQs

What kind of content does text/x-crystal represent?

It represents source code written in the Crystal programming language. This identifier helps web servers and text editors recognize the file structure to apply appropriate syntax highlighting and formatting.

Which file extension is associated with text/x-crystal?

This MIME type is primarily associated with the .cr extension. You can learn more about this specific extension at our cr page.

How do I configure Apache to serve Crystal files correctly?

You can add the MIME type mapping in your .htaccess file or main configuration. Use the directive AddType text/x-crystal .cr to ensure the server identifies these files correctly.

Why does the MIME type start with x-?

The x- prefix indicates that text/x-crystal is a non-standard or experimental type not yet officially registered with the IANA. However, it is widely accepted by developers and tools within the Crystal ecosystem.

Can I run text/x-crystal files directly in a web browser?

No, web browsers cannot execute Crystal source code. If you navigate to a file served as text/x-crystal, the browser will typically display it as plain text or prompt you to download it, rather than running it like JavaScript.

How do I open a file sent as text/x-crystal?

Since these are plain text files, you can open them with any standard text editor like VS Code, Sublime Text, or Notepad++. Specialized editors will often detect the type to provide Crystal-specific syntax coloring.

How do I add support for this MIME type in Nginx?

Open your mime.types file (usually located in /etc/nginx/) and add the line text/x-crystal cr;. This ensures Nginx serves .cr files with the correct headers.

General FAQ

What is a MIME type?

A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.

MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.

MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.

How do I find the MIME type for a file?

You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.

Why are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.