My plan for this year's Advent of Code is to work on quickly producing tidy Haskell solutions using only the libraries included with GHC.
To compile a solver, run
ghc --make -no-keep-hi-files -no-keep-o-files <day_number>
replacing <day_number> with 01, 02, etc. This will produce an executable
with the same name in the current directory.
All solvers take a command line argument indicating which part to solve, and
read their input from stdin. For example, to run part 2 of the Day 1 solver with
the input in input.txt, type:
./01 2 < input.txt