LITH — Light HTTP Server

LITH is a lightweight, fast and secure web server written in standard C11, with no external dependencies. A single small executable (≈ 300 KB) is all you need to publish a website, develop locally with automatic browser reload, or put an application (Node.js, Python, Go...) behind a reverse proxy.

It works the same way on Windows, Linux and macOS.

lith init my-site
cd my-site
lith start
→ http://localhost:8090

New here? The full step-by-step explanation, starting from scratch, is in DOCUMENTATION.md. This README is only a summary.

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Why LITH?

Tiny	≈ 300 KB, a few MB of RAM, ≈ 340 KB Docker image
Zero dependencies	No OpenSSL, no zlib, no runtime: only the system C library
Optional HTTPS	make TLS=1: TLS 1.2/1.3 through a small Rust module (rustls), HTTP → HTTPS redirect, HSTS
Fast	Thread pool, keep-alive, in-memory cache, gzip, sendfile()
Secure by default	Path traversal protection, hidden files blocked, security headers, anti-slowloris
Complete	Reverse proxy, load balancing, WebSocket, live reload, Prometheus metrics
Tested	Unit + integration tests, under sanitizers, CI on 3 operating systems + Docker

Features in 1.0.0

• Static files: in-memory LRU cache, gzip compression, ETag/304, Range requests (video), directory listing, SPA mode, custom error pages.
• Solid HTTP/1.1: keep-alive, pipelining, 100-continue, size limits, precise error codes.
• Security: per-IP rate limiting, per-path Basic authentication, Content-Security-Policy, CORS, .env/.git blocked.
• Reverse proxy: PROXY=/api http://127.0.0.1:3000, several backends in round-robin, automatic failover and health checks.
• Development: lith start --dev reloads the browser on every change (WebSocket).
• Monitoring: /__lith/health, /__lith/status (JSON), /__lith/metrics (Prometheus).
• Operations: daemon mode + lith stop, access log, graceful shutdown, Docker.
• HTTPS (make TLS=1 option): TLS_PORT, PEM certificates (Let's Encrypt), TLS_REDIRECT, HSTS, X-Forwarded-Proto: https sent to backends. Without the option, the core stays 100% C with no dependencies.

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Installation

Download an executable

Get the archive for your system from the GitHub Releases, extract it, and run bin/lith (or bin\lith.exe).

Build it yourself

You need a C11 compiler (gcc/clang, or MinGW-w64 on Windows) and make.

git clone https://github.com/fomadev/lith.git
cd lith
make            # builds bin/lith (or bin/lith.exe)
make test       # unit tests

With HTTPS (you also need Rust; on Windows with MinGW: rustup target add x86_64-pc-windows-gnu):

make TLS=1      # adds the tls/ module (rustls)
make TLS=1 test

Docker

Ready-made image on Docker Hub (linux/amd64 and linux/arm64, ≈ 340 KB):

docker run -p 8090:8090 -v "$PWD/public:/srv/public:ro" fomadev0/lith

Or build it yourself: docker build -t lith .

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Usage

lith start                  # start with lith.conf (port 8090 by default)
lith start 8080             # another port
lith start --dev            # automatic browser reload
lith start -r ./dist        # serve another folder
lith start -d               # in the background (Linux/macOS), then: lith stop
lith check                  # check the configuration
lith health                 # test a running server
lith help                   # all commands

Configuration at a glance

Everything is set in lith.conf (created by lith init), in KEY=VALUE format:

PORT=8090
PUBLIC_DIR=public
GZIP=1
USE_CACHE=1
RATE_LIMIT=50                      # 50 requests/s per IP
AUTH=/admin admin:password         # protected area
PROXY=/api http://127.0.0.1:3000   # send /api to your application
SPA_FALLBACK=1                     # React, Vue, Angular...

# HTTPS (executable built with make TLS=1)
TLS_PORT=443
TLS_CERT=fullchain.pem
TLS_KEY=privkey.pem
TLS_REDIRECT=1                     # http:// -> https://
HSTS=31536000

The full list of settings (more than 35) is described in chapter 5 of the documentation.

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Repository layout

include/   C headers (one per module)
src/       source code: server, HTTP, files, proxy, WebSocket...
tls/       optional HTTPS module in Rust (rustls), built with make TLS=1
tests/     unit tests (C) and integration tests (bash + curl)
public/    sample site served by default
docker/    Docker image configuration
lith.conf  commented configuration

Documentation

Document	Contents
DOCUMENTATION.md	The complete guide, from chapter 0 ("what is a web server?") to production, internal architecture and roadmap
CHANGELOG.md	What changed in each version
CONTRIBUTING.md	How to contribute to the code

License

Distributed under the Fordima Public License (FPL). Using the compiled executables is free, including in companies. Commercial redistribution, embedding the source code in a competing proprietary tool and permanent independent forks require a commercial authorization. See the LICENSE file for the exact terms.