Lemon OS is a UNIX-like 64-bit operating system written in C++.

About Lemon OS

Lemon OS includes its own modular kernel with SMP and networking, window server/compositor and userspace applications as well as a collection of software ports.

If you have any questions or concerns feel free to open a GitHub issue, join our Discord server or email me at [email protected].

Website

Discord Server

Building Lemon OS

Prebuilt Image

Nightly Images - Go to latest job, Lemon.img located under Artifacts
You must be logged in to GitHub to download the image

Before running See System Requirements

More screenshots

Features

• Modular Kernel
• Symmetric Multiprocessing (SMP)
• UNIX/BSD Sockets
• Network Stack (UDP, TCP, DHCP)
• A small HTTP client/downloader called steal
• Window Manager/Server LemonWM
• Terminal Emulator
• Writable Ext2 Filesystem
• IDE, AHCI and NVMe Driver
• Dynamic Linking
• mlibc C Library Port
• LLVM/Clang Port
• DOOM Port

Work In Progress

• XHCI Driver
• Intel HD Audio Driver

Third Party

Lemon OS depends on mlibc, Freetype, zlib, libressl and libpng.

Optional ports include LLVM/Clang, DOOM, Binutils and Python 3.8

Various background images are located here

System requirements

• 256 MB RAM (512 is more optimal)
• x86_64 Processor supporting x86_64-v2 instructions including SSE4.2
  • For QEMU/KVM use -cpu host or at least -cpu Nehalem see this page
• 2 or more CPU cores recommended
• I/O APIC
• ATA, NVMe or AHCI disk (AHCI strongly recommended)

For QEMU run with:
qemu-system-x86_64 Lemon.img --enable-kvm -cpu host -M q35 -smp 2 -m 1G -netdev user,id=net0 -device e1000,netdev=net0
KVM is strongly recommended

Repo Structure

Directory	Description
Applications/	Userspace Applications
Base/	Config, etc. Files copied to disk
Documentation/	Lemon OS Documentation
Extra/	(Currently) vector icons
InterfaceCompiler/	Compiler for interface definition files
Kernel/	Lemon Kernel
LibGUI/	LibGUI (Windowing and widgets)
LibLemon/	LibLemon (Lemon API)
Toolchain/	Toolchain build scripts and patches
Ports/	Build scripts and patches for ports
Resources/	Images, fonts, etc.
Screenshots/	Screenshots
Scripts/	Build Scripts
Services/	Interface definition files
System/	Core system programs and services