What is MIME type "application/x-clojure"?

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

application/x-clojure marks files that hold code written in Clojure, a modern dialect of Lisp that runs on the Java Virtual Machine.
It uses the x- prefix to indicate a non-standard or experimental type. Systems, editors, and build tools look for this type to apply tailored functions.

Code Recognition: Software identifies these files as source code for specialized handling.
Syntax Highlighting: Editors use the MIME type to format code for easier reading.
Tool Integration: Build systems and development tools process these files accurately.

Files marked with this type are typically saved with the CLJ extension.
Additional details on Clojure can be found on its official site.

Associated file extensions

.clj

Usage Examples

HTTP Header

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


    Content-Type: application/x-clojure

HTML

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


    <a href="file.dat" type="application/x-clojure">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', 'application/x-clojure');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.clj

FAQs

What kind of content does application/x-clojure represent?

This MIME type represents source code written in Clojure, a dynamic functional programming language that runs on the Java Virtual Machine (JVM). It allows web servers and development tools to identify files, usually with the .clj extension, as executable logic rather than plain text.

How do I configure Apache to recognize Clojure files?

You can map the extension to the MIME type in your .htaccess file or main configuration. Add the line AddType application/x-clojure .clj to ensure the server sends the correct Content-Type header when serving source files.

Is application/x-clojure a standard IANA type?

No, the x- prefix indicates that it is a non-standard or private subtype. While not officially registered with IANA, it is a de facto standard used by the Clojure community and tools like Leiningen and Boot to identify source assets.

Should I use text/x-clojure or application/x-clojure?

Both are commonly seen, but text/x-clojure is often preferred for display in browsers because it indicates the content is readable text. However, application/x-clojure is appropriate when the file is being transferred as a data payload or an application component intended for execution or compilation.

What software opens files with this MIME type?

Since these are plain text source files, any text editor can open them, but specialized IDEs provide the best experience. Popular tools include Emacs (with CIDER), IntelliJ IDEA (with Cursive), and VS Code (with Calva), all of which use the MIME type to trigger syntax highlighting.

Are there security risks when handling application/x-clojure files?

Yes, because these files contain code that runs on the JVM, they can execute system-level commands if processed. You should treat uploaded .clj files with the same caution as .java or .exe files and never execute them from untrusted sources.

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.