Jolly Good Emulation

Simple. Minimal. Unembellished. Yes, yes... Jolly Good!

Code Available on Gitlab

Jolly Good Emulation is a preservation oriented emulation project with a focus on reusability. As a side effect, it offers emulation technology that extreme minimalists may find tolerable.

Mission and Goals

  • Provide a minimalist emulation framework
  • Create lean, high quality console emulators
  • Build robust and reusable emulation components
  • Strict adherence to standards to prevent bitrot
  • Focus on simplicity and readability


  • Frills and frippery
  • Distribution of binaries
  • Sacrifices to quality
  • Ports to novelty hardware

Which systems are emulated?

System Emulator Core
Atari 7800 ProSystem JG Forked!
Atari Lynx Mednafen
ColecoVision JollyCV Home Steeped!
Nintendo Entertainment System (FDS) Nestopia JG Forked!
Super Nintendo Entertainment System bsnes-jg Forked!
Nintendo Game Boy/Game Boy Color Gambatte JG Forked!
Nintendo Game Boy Advance mGBA
Nintendo Virtual Boy Mednafen
Sega SG-1000/Master System Cega Home Steeped!
Sega Mega Drive/Genesis (CD) Genesis Plus GX
Sega 32X PicoDrive
Sega Saturn Mednafen
Sega Game Gear Cega Home Steeped!
NEC PC Engine/TurboGrafx-16 (CD) Mednafen
SNK Neo Geo AES/MVS Geolith Home Steeped!
SNK Neo Geo Pocket Color Mednafen
Sony PlayStation Mednafen
WonderSwan/WonderSwan Color Mednafen
Vectrex Vecx JG Forked!
Also available:

Have you got a license for that?

The Jolly Good Reference Frontend, licensed under the BSD 3-Clause "New" or "Revised" license, and the reference implementation of The Jolly Good API, licensed under the zlib License, are Free and Open-Source Software. Some emulators are not Free Software due to non-commercial clauses, but are compatible with these licenses.

In most jurisdictions, you are legally permitted to format shift the games you own to be played using emulators. There is also a wealth of free homebrew available.

What is the release status?

API 1.0.0
Frontend 1.1.0

The software and all components are considered stable unless otherwise noted.

Please do not report issues to upstream emulator developers, unless they are also in the upstream build.

Which host platforms are supported?

Linux   DragonFly BSD   FreeBSD   NetBSD   OpenBSD   macOS   Windows


The language standard is ISO C99
(ISO/IEC 9899:1999, POSIX.1-2001).
The reference frontend requires:
  • OpenGL 3.3 or GLES 3.0
  • SDL2
  • SpeexDSP