What Language is Apache Primarily Written In?

This article provides a quick overview of the primary programming language used to develop the Apache HTTP Server, one of the most long-standing and widely used web servers in the world. It explores the core language behind its architecture, the reasons for this technical choice, and the minor roles played by other supporting languages in the broader Apache ecosystem.

The Core Language: C

The Apache HTTP Server is primarily written in C. Since its initial release in 1995, the core architecture of the server has relied on C to achieve high performance, low-level memory management, and maximum efficiency.

Because web servers need to handle thousands of concurrent requests rapidly while consuming minimal system resources, C was—and remains—the ideal choice for building its foundational infrastructure.

The Role of the Apache Portable Runtime (APR)

To keep the codebase maintainable across different operating systems (like Linux, Unix, and Windows), the developers created the Apache Portable Runtime (APR).

• System Abstraction: The APR is also written in C and acts as a compatibility layer.
• Platform Independence: It allows the main Apache source code to interact with OS-specific features without needing complete rewrites for each platform.

Supporting Languages in the Apache Ecosystem

While C makes up the vast majority of the core web server, other languages are utilized for supporting tasks within the project:

• Perl and Python: Often used for configuration scripts, automated testing suites, and build tools.
• XML and HTML: Used extensively for documentation and default configuration templates.

It is also worth noting that “Apache” can refer to the Apache Software Foundation (ASF), which hosts hundreds of other open-source projects. While the classic HTTP Web Server is written in C, other famous Apache projects are written in different languages, such as Apache Tomcat (Java), Apache Spark (Scala/Java), and Apache CouchDB (Erlang). However, for the core web server itself, C remains the dominant language.