我也碰到这个问题：Runing mix new app_first failed in Elixir。
这是一条信息：

Erlang版本是正常的：

github@localhost:$ erl
Erlang/OTP 24 [erts-12.2] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1]

长生不老药的版本是正常的

github@localhost:~/elixir-otp-24$ bin/elixir --version
Erlang/OTP 24 [erts-12.2] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1]

Elixir 1.14.0 (compiled with Erlang/OTP 24)

但混合是不正常的

github@localhost:~/elixir-otp-24$ bin/mix
{"init terminating in do_boot",{badarg,[{erlang,apply,[{'Elixir.Kernel.CLI.Config',[],<<".">>,[],true,[],[],false},update_commands,[#Fun<Elixir.Kernel.CLI.18.41400255>]],[{error_info,#{module=>erl_erts_errors}}]},{'Elixir.Kernel.CLI',process_argv,2,[{file,"lib/kernel/cli.ex"},{line,191}]},{'Elixir.Kernel.CLI',main,1,[{file,"lib/kernel/cli.ex"},{line,14}]},{init,start_em,1,[]},{init,do_boot,3,[]}]}}
init terminating in do_boot ({badarg,[{erlang,apply,[{_},update_commands,[_]],[{_}]},{Elixir.Kernel.CLI,process_argv,2,[{_},{_}]},{Elixir.Kernel.CLI,main,1,[{_},{_}]},{init,start_em,1,[]},{init,do_boot,3,[]}]})

Crash dump is being written to: erl_crash.dump...done

我试过很多方法，比如从源头开始建设，但都失败了。