This is a stubborn attempt to participate in the Advent of Code 2020 using "pure" R7RS-large in Guile. The catch is that Guile doesn't support R7RS-large, so I need to cobble it together from the relevant SRFI reference implementations.
Solving 50 problems in 25 days over the holiday period is a tall order, so I don't realistically expect to have everything completed in time. My main objectives are to get comfortable with some of the R7RS-large libraries, identify gaps in Guile's R7RS-large support, and perhaps find something to contribute to improve that situation.