CJIT is a C interpreter based on tinyCC that compiles C code in-memory and runs it live. It is released as a small, all-in-one executable that can do a lot, including call functions from any installed library on Linux, Windows, and MacOSX.

Homepage at Dyne.org/CJIT.

🚀 Quick start

Download the latest CJIT release for your system.

Launch CJIT from a terminal console command prompt: one can mix c source files and dynamic libraries as arguments:

./cjit.exe mysource.c mylib.dll

Take a tour with the CJIT tutorial.

📦 Download the demo

The CJIT demo package comes with running examples

🪟 On Windows

iex ((New-Object System.Net.WebClient).DownloadString('https://dyne.org/cjit/demo'))

🍎 / 🐧 On Apple/OSX and GNU/Linux

curl -sL https://dyne.org/cjit/demo.sh | bash

📖 and follow the The CJIT tutorial

⚙️ Build from source

There are various build targets, just type make to have a list:

✨ Welcome to the CJIT build system
🛟 Usage: make <target>
👇 List of targets:
 _
 ------           __ Production targets
 linux-x86        🐧 Build a dynamically linked cjit using libs found on Linux x86
 win-wsl          🪟 Build cjit.exe for WIN64 on an Ubuntu WSL VM using gcc-mingw-w64
 win-native       🪟 Build cjit.exe for WIN64 on Windows Server
 apple-osx        🍎 Build cjit.command for Apple/OSX using clang static
 _
 ------           __ Debugging targets
 debug-gdb        🔬 Build using the address sanitizer to detect memory leaks
 debug-asan       🔬 Build using the address sanitizer to detect memory leaks
 self-host        💎 Build a CJIT that builts itself (embed its source)
 _
 ------           __ Testing targets
 check            🧪 Run all tests using the currently built binary ./cjit
 check-ci         🧪 Run all tests using the currently built binary ./cjit
 _
 ------           __ Installation targets
 install          🔌 Install the built binaries in PREFIX
 clean            🧹 Clean the source from all built objects

Manpage

When installed on UNIX systems, CJIT(1) has a manpage! try man cjit after installing.

It is also visible online at dyne.org/docs/cjit.

This manual gives you insights about the CJIT command-line options.

🔬 Internals

CJIT is a bit complex inside.

1. It relies on tinycc to compile C code in-memory and run it immediately.
2. It detects automatically the system on which its running and auto-configures to support most features.
3. It embeds all C code and headers in cjit/assets making them available to all running code.
4. To embed them creates a tar.gz of assets at build-time and decompresses them at run-time in a temporary dir.
5. It ships a non-exclusive, opinionated selection of libraries useful to quickly script advanced applications in C.

The CJIT's Frequently Asked Questions page may provide more information.

📑 Acknowledgements

CJIT is copyright (C) 2024-2025 by the Dyne.org foundation. Designed, written and maintained by Jaromil. Free and open source (GNU General Public License v3).

The TinyCC core component is copyright (C) 2001-2004 by Fabrice Bellard. TinyCC is also free and open source (GNU Lesser General Public License).

The CJIT manual offers more information on CJIT licensing.