Debugging can be done using godebug.
Install it, then insert a breakpoint anywhere you want:
_ = "breakpoint"
And run the debugger:
godebug run -instrument github.com/moncho/dry,github.com/moncho/dry/app,github.com/moncho/dry/docker,github.com/moncho/dry/ui,github.com/moncho/dry/appui main.go