IFCP Contest 2021

The repository contains almost all of the source code used to run ICFP Contest 2021. There are a number of components:

• website/: This is the source for the website at https://icfpcontest2021.github.io.
• spec/: The source code of the specification, as Pandoc markdown.
• problems/: The problems released during the contest.
• toolchain/: The toolchain contains the bulk of our code. It is a Haskell project containing the database, judge, webserver, and numerous other utilities.
• infra/: Some deployment stuff, most importantly contains a nix file to build docker images that we can deploy in a pretty straightforward way.

Website

Development

This site only uses a couple standard utilities, like bash, sed, date, make. It should work out of the box on most linux systems.

To build the website, simply use:

make website

This produces a _site directory with static files. You can preview those directly using a browser, e.g.:

firefox website/_site/index.html

Or you can use a simple HTTP server, e.g:

python -m http.server --directory website/_site

Spec

Building

make spec

Toolchain

Building and installing

make toolchain

Database

For some tools, you need to have a Postgres instance running somewhere. First, create a database, then run the migrations that set up the schema. For example:

sudo createuser jasper                            # set up local user
createdb icfpc                                    # create database
for i in toolchain/db/*; do psql icfpc <$i; done  # apply migrations

Configuring

• BRAINWALL_PG_CONNECTION_STRING: where to find the database.
• BRAINWALL_BIND_PORT: port to serve the web app on.
• BRAINWALL_BIND_ADDRESS: address to listen on for the web app.

Tools

After installing, you should have a number of executables in your $PATH.

Noteworthy:

• brain-wall-web: Worker to run the web portal.
• brain-wall-prosecutor: Worker to judge solutions in the database.
• brain-wall-judge: CLI utility to judge a pose.
• brain-wall-render-svg: Render an SVG for a problem (and possibly a pose).
• brain-wall-parse-svg: Takes an SVG that has a elements with IDs hole and figure and tries to turn this into a problem.
• brain-wall-random-problem: Generate a random problem.

Miscellaneous:

• brain-wall-animate: Renders an animation given a problem and pose.
• brain-wall-download-sources: Download the source code submitted by participants.
• brain-wall-estimate-epsilon: Try to find a reasonable eps value for a problem.
• brain-wall-gallery: Generates an HTML gallery of the best solutions per problem.
• brain-wall-generate-bonus: A utility to assign some random bonuses.
• brain-wall-generate-figure: Generates a random figure.
• brain-wall-generate-hole: Generates a random hole.
• brain-wall-insert-problems: Submits problems to the database so they will show up in the web portal.
• brain-wall-jasper-gen: Fairly dumb problem generator.
• brain-wall-jasper-solver: Fairly dumb solver.
• brain-wall-random-many: Generate multiple random problems.
• brain-wall-reset-password: Reset the password for a participant.
• brain-wall-scoreboard: Renders the scoreboard in plain text.
• brain-wall-texture: Texturing experiment for planar figures.

Most of these have an -h flag to show supported options.

Infra

Building

make images