Because these are community-made homebrew projects rather than commercial retail games, you won't find a standard ROM on official storefronts. Where to look : You can generally find the files for on community hubs like Homebrew Hub Safety Tip
Mojang and Nintendo never developed or published Minecraft for the original DS (released 2004–2011). The DS hardware — with its 67 MHz ARM9 processor, 4 MB of RAM, and limited 3D capabilities — simply lacked the power to run Minecraft’s infinite worlds, physics, and mob AI. nintendo ds minecraft rom link
Includes a PC-based tool to generate specific world sizes, like 128x128 maps. Where to find it: The source code and official releases are hosted on the smealum GitHub page 2. Mini 3D (The Modern Contender) 4 MB of RAM