If only I knew... Unfortunately I never managed to get all builds working in a Docker environment. But here we go anyway. The following targets should build successfully:

• x86_64-unknown-linux-musl
• i686-unknown-linux-musl
• aarch64-unknown-linux-gnu (eg. Rock64)
• arm-unknown-linux-gnueabihf (eg. Raspberry Pi 2+ - NOT built in default script)
• arm-unknown-linux-gnueabi (eg. Pi1 - NOT built in default script)

Build the docker image from the root of the project with the following command:

$ docker build -t spotty-cross -f docker/Dockerfile .

The resulting image can be used to build spotty for aforementioned platforms.

$ docker run -v ~/.spotty-build:/build -v $PWD:/src spotty-cross

The compiled binaries will be located in a sub folder called releases.

If only one architecture is desired, cargo can be invoked directly with the appropriate options:

$ docker run -v ~/.spotty-build:/build -v $PWD:/src spotty-cross cargo build --release
$ docker run -v ~/.spotty-build:/build -v $PWD:/src spotty-cross cargo build --release --target arm-unknown-linux-gnueabihf
$ docker run -v ~/.spotty-build:/build -v $PWD:/src spotty-cross cargo build --release --target aarch64-unknown-linux-gnu

Resulting files could be found in ~/.spotty-build and sub-folders.