Currying is not very straight forward in Elixir, but it is still doable

currying_elixir.ex

defmodule Math do
  def sum(a,b), do: a+b
  
  def add1(a) do
     f = fn(a) -> sum(1,a) end
     f.(a)
  end
  
  def three() do
    f = fn() -> add1(2) end
    f.()
  end
end