Via @maltby – Just released this today – GB Studio, a drag and drop Game Boy game maker for Windows, Mac and Linux. Free and open source!

GB Studio ia a free and easy to use retro adventure game creator for Gameboy. Run games on any compatible emulator, if you’ve got a flash cart you can play them on a real console! GB Studio comes with a web based emulator that works on mobile. You can quickly export your games to play in a browser or upload to Itch.io.

• Visual game builder with no programming knowledge required.
• Design your graphics in any editor that can output PNG files e.g. Photoshop, Tiled, Aseprite.
• Example project included to get started right away.
• Make top down 2D JRPG style adventure games.
• Build real GB Rom files which can be played in an emulator or on device using USB Carts.
• Build a HTML5 playable game that also works on mobile and can deployed to any web server or uploaded to Itch.io.
• Built for macOS, Windows and Linux.
• Supports both mac OS light and dark mode.
• Includes the full tools that were used to build Untitled GB Game, free to play on Itch.io.

See the video below and the website for additional details and uploads.