This looks horrible (formatter)

authorize.ex

defmodule Api.Authorize do
  alias Account.Models.User

  def board?(board_id, %User{} = user, available_permissions, required_permissions) do
    with {:ok, board} <- Tracker.Board.find(board_id),
         true <-
           Tracker.OrganizationMembers.user_in_organization?(user.id, board.organization_id),
         ^required_permissions <-
           Enum.to_list(
             MapSet.intersection(
               MapSet.new(required_permissions),
               MapSet.new(available_permissions)
             )
           ) do
      true
    else
      _ -> false
    end
  end
end

As Jose Valim pointed out, usually a sign of needed refactoring...I did that, and this is what I ended up with: https://gist.github.com/jeremytregunna/95830562d9b3a70e0c898d9694445eb5