Co-maintainer here: we also did this cool thing where we reused the same go codebase across our clients. We have a go package called olm (on our Github and following our animal theme) that implements all of the VPN capabilities. It creates the tunnel, monitors the peers, syncs with the Pangolin server. This itself is a binary that can run on its own as like our own little VPN kernel module - then in the different applications we use olm to trigger the tunnel. This is easy on Windows as the whole app is go based, but on Android, Mac, and iOS we use C bindings to compile it as a shared library into the application. Then the native application imports parts of the module to initiate the tunnel and handle the tunneling. On iOS and Macos this is handled in a "Network Extension" which is a secure environment Apple runs tunneling applications in, so we use a unix socket to communicate with the olm tunneling kernel to show status to the user and handle commands.
Everything, from the server to the clients, is fully open-source and you can even self-host the whole stack. We’d love to hear what you think and I'm happy to answer any questions!
Co-maintainer here: we also did this cool thing where we reused the same go codebase across our clients. We have a go package called olm (on our Github and following our animal theme) that implements all of the VPN capabilities. It creates the tunnel, monitors the peers, syncs with the Pangolin server. This itself is a binary that can run on its own as like our own little VPN kernel module - then in the different applications we use olm to trigger the tunnel. This is easy on Windows as the whole app is go based, but on Android, Mac, and iOS we use C bindings to compile it as a shared library into the application. Then the native application imports parts of the module to initiate the tunnel and handle the tunneling. On iOS and Macos this is handled in a "Network Extension" which is a secure environment Apple runs tunneling applications in, so we use a unix socket to communicate with the olm tunneling kernel to show status to the user and handle commands.
Everything, from the server to the clients, is fully open-source and you can even self-host the whole stack. We’d love to hear what you think and I'm happy to answer any questions!