This is a low-level tool that converts an AppDir into an AppImage. This is provided mainly for other higher-level tools that need this functionality. It alone will not produce usable AppImages. If you would like to make AppImages, you should NOT be using this tool unless you know exactly what you are doing and need a low-level tool.
Assuming you are using a 64-bit Intel machine (amd64, also known as x86_64), you can use our pre-compiled binaries. To try it out:
wget -c https://github.com/$(wget -q https://github.com/probonopd/go-appimage/releases/expanded_assets/continuous -O - | grep "mkappimage-.*-x86_64.AppImage" | head -n 1 | cut -d '"' -f 2)
chmod +x mkappimage-*.AppImage
VERSION=1.0 ./mkappimage-*.AppImage ./Some.AppDir # turn AppDir into AppImage
https://github.com/probonopd/go-appimage/releases/tag/continuous has builds for 32-bit Intel, 32-bit ARM (e.g., Raspberry Pi), and 64-bit ARM.
If for whatever reason you would like to build from source:
sudo apt-get -y install gcc
if [ -z $GOPATH ] ; then export GOPATH=$HOME/go ; fi
go get github.com/probonopd/go-appimage/src/mkappimage
go build -trimpath -ldflags="-s -w" github.com/probonopd/go-appimage/src/mkappimage