ICFP Contest 2021

ICFP Contest 2021 took place 12:00 PM Friday 9 July - 12:00 PM Monday 12 July UTC.

ICFP Contest 2021

Contest Presentation Video

Tue, 31 August 12:00 UTC

You can now watch the contest presentation video right here or on YouTube.

Final Results, Winners Announced

Wed, 25 August 13:30 UTC

We have announced the winners at the ICFP 2021 Conference.

First prize: RGBTeam
C++ and Rust are the programming tools of choice for discriminating hackers.
Second prize: Unagi
Rust is a fine programming tool for many applications.
Third prize: Special Weekend
Rust, TypeScript and Go are also not too shabby.
Winner of the lightning division: Special Weekend
Rust, TypeScript and Go are very suitable for rapid prototyping.
Judges' prize: manarimo
manarimo are an extremely cool bunch of hackers.

The scoreboards for the full division and lightning division have been updated as well with the complete rankings.

We will provide a link to the video recording of the programming contest report as soon we have it. Congratulations to the winners, and thanks again to everyone who took part!

Contest Code Open Sourced

Fri, 30 July 17:45 UTC

We're excited to announce that we have open sourced the code that we used to put together the contest under the BSD3 license.

You can find the code alongside the source for this website in this repository.

Contest winners notified

Wed, 28 July 17:54 UTC

We've sent e-mails notifying the winners. The final scoreboard will be reavealed and the winners will be announced at the ICFP conference on August 23-25, 2021.

Partial scoreboard, poses.live future and Team Writeups

Tue, 13 July 21:00 UTC

The final scoreboard for the lightning and the full division is now available. Teams with 0 points are not shown, and the top 15 teams in both rounds have been randomly shuffled, and their score hidden to keep some intrigue. We will get in touch with the winners soon.

Some teams have already posted interesting writeups on how they approached the problem. We started collecting these here.

Several people have asked what will happen to the poses.live website now that the contest is over. Since there is some interest in keeping it around, the organisers will move this to a smaller instance on a personal server. All data from the contest will be wiped, and teams will have to re-register on this new instance if they want to continue trying it out. There will be significant downtime this week as we move it.

We will also release source code of the portal and judge after the contest presentation at ICFP 2021. Thanks again to everyone for taking part in this!

It's over!

Mon, 12 July 12:00 UTC

The ICFP Contest is over for this year!

We would like to thank all teams for particating, and we hope people had a lot of fun implementing UIs and solvers for the problem, regardless of how well they did on the scoreboard.

The poses.live server will remain up for a bit more. If you want to qualify for prizes, don't forget to upload your source code on your team profile page within the next 12 hours.

The winners of the contest will be announced at the 2021 International Conference on Functional Programming, taking place Sun 22 - Fri 27 August.

Minor clarification in specification

Sun, 11 July 19:45 UTC

We added a clarification to the WALLHACK bonus in the the specification.

Final bonus added, new problems added

Sun, 11 July 12:00 UTC

We have now extended the specification with a last bonus. We have also added new problems, and added bonuses to existing problems. This is the last modification to the specification that will be made, barring unforeseen errors.

We will freeze the scoreboard on Mon, 12 July at 11:00 UTC.

Participants must submit their source code to be elligible for prizes. This can be done via the team profile page in the portal. We will accept submissions of source code until Tue, 13 July at 00:00 UTC.

Added WALLHACK bonus to spec, more problems added

Sun, 11 July 00:00 UTC

We added a new type of bonus to the specification. We've also added new problems and added new bonuses to the existing problems.

Correction in GLOBALIST specification

Sat, 10 July 14:13 UTC

We fixed a naming inconsistency in the definition of the GLOBALIST bonus in the specification.

Bonuses added to spec, new problems added

Sat, 10 July 12:00 UTC

The Lightning Division (first 24 hours of the contest) has now ended. We hope everyone had fun so far!

We have now extended the specification with bonuses, which allow you gain certain advantages in other problems.

We have also added 10 new problems to poses.live.

The scoreboard will remain frozen for another half hour, until 12:30 UTC.

New problems added, HTTP API addition

Sat, 10 July 00:00 UTC

We have added 19 new problems to poses.live.

We would like to remind everyone that the Lightning Division ends in twelve hours on Sat, 10 July 12:00 (noon) UTC.

To keep things exciting, we will freeze the scoreboard temporarily on Sat, 10 July from 11:30 to 12:30 UTC. We've also limited the scoreboard to teams with at least one valid solution.

Additionally, we have updated the specification with a new API endpoint to obtain some information about submitted poses.

ICFPC2021 has started

Fri, 09 July 12:00 UTC

Welcome to ICFPC2021!

We have published a first version of the specification.

Teams can register, submit solutions and view the current scoreboard at our web portal located at poses.live.

Good luck, and have fun!


Fri, 09 July 08:49 UTC



Thu, 08 July 16:30 UTC



Wed, 07 July 15:36 UTC

We strongly recommend participants this year to wear waterproof clothing and leave their phone in a locker.

Atom Feed

Mon, 05 July 09:52 UTC

An atom feed is now available for contest updates.

Discord Server

Sun, 04 July 20:00 UTC

We have set up a Discord server for participants to communicate and socialise during the contest. You can join the server here. Please note that we use the Berlin Code of Conduct. This website remains the single source of truth for the contest and all announcements will be posted here.