melonDS-emu/melonDS

Overview

melonDS is a Nintendo DS emulator with partial DSi support, written in C++ and released under GPL-3.0. Its stated goal is to emulate the hardware correctly and quickly rather than merely run games, and the project acknowledges that some areas—notably DSi emulation and OpenGL rendering—remain works in progress. It is aimed at people who want to play DS titles on a desktop and at developers interested in emulator internals.

Getting started

The supported way to obtain the emulator is through the downloads page on the official website (melonDS downloads). Firmware boot requires a BIOS/firmware dump from an original DS or DS Lite; direct game boot does not. Firmware from a DSi or 3DS is not bootable and only supplies configuration data, so it is suitable only for direct boot (README usage notes). Accepted firmware sizes differ: 128 KB for DSi/3DS DS-mode firmware, 256 KB for regular DS firmware, and 512 KB for iQue DS firmware. DS BIOS dumps from a DSi or 3DS can be used without compatibility issues, while DSi BIOS dumps in DSi mode are not compatible.

After launching, the interface is described as straightforward; load a firmware/BIOS image if you want firmware boot, then open a ROM. The README does not document the step-by-step menu flow, so the website and community channels are the places to resolve interface questions.

Building from source

Build instructions live in BUILD.md, which is the reference for dependencies and platform commands. CI workflows cover Windows, Ubuntu, macOS and BSD (Windows build, Ubuntu build, macOS build, BSD build), which indicates those platforms are exercised by the project's own builds.

Constraints and status

• Legacy DS firmware is needed for firmware boot; DSi/3DS firmware files only carry configuration data.
• DSi BIOS dumps used in DSi mode are not compatible.
• DSi emulation, OpenGL rendering, netplay, pixel-perfect 3D output and rendering screens to separate windows are listed as TODO items, not finished features (TODO list).
• Big-endian hosts such as Wii are deferred to low priority.
• The project is GPL-3.0; redistribution and modification must follow that license (license text).

HotRepo's take

In the 2026-11-09 C++ daily snapshot, melonDS recorded 3 new stars and reached 12th place in that language list. That single observation confirms current activity in the C++ ranking but does not establish a longer trend, and no all-language daily rank has been recorded for the project. The TODO list is more informative than the star count: it shows DSi emulation and OpenGL rendering as active gaps, so users whose interest is specifically DSi titles or rendering features should check current release notes rather than assume full support.