lsp mode for dart support on spacemacs

I want to setup dart support on spacemacs, android studio takes up too much resource and I already have spacemacs keybindings on muscle memory. I have had a look at Averrins's implementation which is unfortunately deprecated and there is a proposal that I use lsp mode for dart. tried following through this issue on GitHub but cannot customize it for dart-mode. How can I use lsp mode for dart support on spacemacs (I am on the develop branch - emacs 26.1)