===> Uncaught error in rebar_core.

[SaveMe0]

alberto@debian:~/emqtt/_build/emqtt/rel/emqtt/bin$ rebar3 shell
===> Verifying dependencies...
===> Uncaught error in rebar_core. Run with DIAGNOSTIC=1 to see stacktrace or consult rebar3.crashdump

Error: {badmatch,[]}
[{rebar_prv_shell,kill_old_user,0,[{file,"rebar_prv_shell.erl"},{line,181}]},
{rebar_prv_shell,setup_shell,1,[{file,"rebar_prv_shell.erl"},{line,143}]},
{rebar_prv_shell,shell,1,[{file,"rebar_prv_shell.erl"},{line,123}]},
{rebar_core,do,2,[{file,"rebar_core.erl"},{line,155}]},
{rebar3,run_aux,2,[{file,"rebar3.erl"},{line,193}]},
{rebar3,main,1,[{file,"rebar3.erl"},{line,66}]},
{escript,run,2,[{file,"escript.erl"},{line,904}]},
{escript,start,1,[{file,"escript.erl"},{line,418}]}]