Encountered error when running expm

[lowks]

My versions:

Elixir: 0.12.4

Erlang: V5.10.3

expm: latest

When I try to run any expm command I get this:

lowks@lowkster:~/src/elixir/radpath> expm --help
** (FunctionClauseError) no function clause matching in Keyword."-merge/2-lc$^0/1-0-"/1
    /home/expm/elixir/lib/elixir/lib/keyword.ex:300: Keyword."-merge/2-lc$^0/1-0-"(nil)
    /home/expm/elixir/lib/elixir/lib/keyword.ex:300: Keyword.merge/2
    /home/expm/expm/lib/expm.ex:54: Expm.main/1
    /home/expm/elixir/lib/elixir/lib/kernel/cli.ex:39: Kernel.CLI.run/2
    escript.erl:747: :escript.run/2
    escript.erl:277: :escript.start/1
    :init.start_it/1
    :init.start_em/1

If I am doing something wrong some help would be appreciated.