NGINX

NGINX is a high-performance HTTP server, reverse proxy, load balancer, mail proxy, and generic TCP/UDP proxy. The codebase is a single C99 program built from auto/configure + make that produces one binary, objs/nginx, plus a small set of bundled config files. The same binary can serve static files, terminate TLS, proxy to upstream HTTP/FastCGI/uwsgi/SCGI/gRPC backends, do HTTP/2 and HTTP/3 (QUIC), proxy POP3/IMAP/SMTP, and load-balance arbitrary TCP/UDP streams.

The project was started in 2002 by Igor Sysoev as a faster alternative to Apache and the canonical "C10K" web server. It is now stewarded by F5 and developed in this repository as the "mainline" branch — the upstream feeds both the open-source nginx distribution and F5's commercial NGINX Plus.

What's in the repo

• src/ — every line of nginx code, organized by subsystem (core/, event/, http/, mail/, stream/, os/, misc/)
• auto/ — the hand-written configure system. Shell scripts that probe the host, generate objs/Makefile and objs/ngx_auto_config.h, and stitch together the static module list
• conf/ — sample nginx.conf and MIME type tables shipped with the install
• contrib/ — small utilities (geo2nginx.pl, vim syntax files, Unicode-to-NGINX charset converter)
• docs/ — the XML/XSLT toolchain that builds nginx.org/en/docs and the man page
• misc/ — auxiliary build assets (docs/man, release tooling)

Where to start

If you want to…	Read
Understand the runtime architecture	Architecture
Build nginx and run the test suite	Getting started
Look up a project-specific term	Glossary
Trace an HTTP request through the code	systems/http/request-lifecycle
Write a new module	systems/configuration and primitives/module
See what's actually inside the repo today	By the numbers
Trace 23 years of history	Lore

Quick stats

• Languages: C (~99 %), with one C++ file (src/misc/ngx_cpp_test_module.cpp — a build sanity check) and a Perl XS module (src/http/modules/perl/)
• Source files: 260 .c files, 135 .h files
• LOC: ~247,000 lines of C across src/, auto/, contrib/, docs/
• Modules: ~80 bundled modules across http/, stream/, mail/, event/
• Supported OSes: Linux, FreeBSD, macOS, Solaris, AIX, Windows (proof-of-concept)
• License: 2-clause BSD

Project status

This repository is the canonical mainline source. Tagged stable branches live elsewhere; the master branch here always carries the latest features and bugfixes. See Lore for the full history of branches, rewrites, and deprecations.