Skip to content

An updated version of GBDK, C compiler, assembler, linker and set of libraries for the Nintendo Gameboy, Nintendo Entertainment System, Sega Master System, Sega Game Gear.



Folders and files

Last commit message
Last commit date

Latest commit


Repository files navigation


GBDK is a cross-platform development kit for sm83, z80 and 6502 based gaming consoles. It includes libraries, toolchain utilities and the SDCC C compiler suite.

Supported Consoles: (see docs)

  • Nintendo Game Boy / Game Boy Color
  • Analogue Pocket
  • Sega Master System & Game Gear
  • Mega Duck / Cougar Boy
  • NES

Experimental consoles (not yet fully functional)


Current Release

Current Release Downloads

GBDK-2020 Linux Release GBDK-2020 MacOS Release GBDK-2020 Windows 64 Bit Release GBDK-2020 Windows 32 Bit

Upgrading to a new version? Check the Migration notes. You can find older versions here.

For a full list of changes see the ChangeLog file or online Docs.

Build status

GBDK Build and Package


GBDK includes extensive documentation. A good place to begin is the Getting Started Section.

Check the Links and Third-Party Tools Section for a list of recommended emulators, graphics tools, music drivers and more.

For SDCC you can check its website and the manual


Most users will only need to download and unzip the latest release

Then go to the examples folder and build them (with compile.bat on Windows or running make). They are a good starting point.

The sources in this repo are only needed if you want to re-compile GBDK-2020 yourself instead of using the release binaries linked above.

Discord servers

  • gbdk/zgb Discord - For help with using GBDK (and ZGB), discussion and development of gbdk-2020

  • gbdev Discord - There is a #gbdk channel and also people with a lot of Game Boy development knowledge

  • SMS Power! Discord - Additional SMS & Game Gear discussion and resources.


Current status

  • Updated CRT and library that suits better for game development
  • SDCC Versions
    • A custom build of SDCC is used with patches to support Sega GG/SMS and the Nintendo NES. See the github workflow for details of how to patch and build SDCC.
    • The default calling convention changed in SDCC 4.2. This is supported starting with GBDK-2020 4.1.0. Older versions of GBDK should use SDCC builds #12539 or older (see per-version GBDK notes).
  • The compiler driver lcc supports the latest sdcc toolchain.


Over the years people have been complaining about all the GBDK issues caused by a very old version of SDCC (the compiler). This is a proper attempt of updating it while also keeping all the old functionality working, like support for banked code and data and so on.

The last version in the OLD repo is 2.96 although releases are available until 2.95-3. Version 2.96 is the starting point of this repo.

Build instructions

Unless you are interested on recompiling the sources for some reason (like fixing some bugs) you don't need to build GBDK

  • Windows only: Download and install mingw
  • Clone, download this repo or just get the source from the releases
  • Download and install the PATCHED sdcc builds from the separate repo for that (
  • On Linux don't use package managers The latest release available won't work, you need to compile or download one of the nightlies
  • Create SDCCDIR environment variable, that points into the folder, where you installed sdcc
  • Open command prompt or a terminal, go to the root directory of the repo and run make


An updated version of GBDK, C compiler, assembler, linker and set of libraries for the Nintendo Gameboy, Nintendo Entertainment System, Sega Master System, Sega Game Gear.








No packages published