This is a fairly simple Hello World example that illustrates how to use nds-rs (as of the time of writing this, nds-sys because nds-rs is kinda empty) and how to build a playable NDS file
Keep in mind that you need to have the appropriate Devkitpro packages for NDS installed and your path variables set.
First, start by compiling the code with
cargo +nightly build --release -Z build-std=core,alloc --target thumbv5te-none-eabi.jsonfor a release build or
cargo +nightly build -Z build-std=core,alloc --target thumbv5te-none-eabi.jsonfor a debug build.
Next(At some point I'll write a script that automates this), go to the thumbv5te-none-eabi/release or thumbv5te-none-eabi/debug (depending on what type of build you did on the previous step) subdirectory inside the target directory and run the following command on your terminal:
ndstool -c nds_testing_rs.nds -9 nds-testing -b /opt/devkitpro/libnds/icon.bmp "hello_world_rust;built with devkitARM & rust;http://devkitpro.org"(Keep in mind you need to have the ndstool binary that's provided by devkitpro on your path) It will then generate a .nds file on the folder you ran the command on.
... And you're done!