For some reason doing ctrl+shift+n in the term that ran the nix-shell does not get me a term in the same nix-shell, but running ctrl+shift+n in a new-terminal from the nix-shell gets me a term in the nix-shell
Also if I can make ctrl+shift+n always keep make a new term in the nix-shell,
then it could be really usefull to have a reload the default env command,
that plus cd would basicly get me back to a "clean" shell
new-terminal still remains usefull for combining with commands i.e. new-terminal kak