pub type DayRunner = fn(String) -> Solution
pub type RunnerMap = Map(Day, DayRunner)
pub type Solution = #(Int, Int)
pub fn build_runners_from_days_dir() -> Result( Map(Int, fn(String) -> #(Int, Int)), Snag, )
pub fn register_command(glint: Command, runners: Map( Int, fn(String) -> #(Int, Int), )) -> Command
pub fn run(input: CommandInput, runners: Map( Int, fn(String) -> #(Int, Int), )) -> Nil