What is CCJam?

CCJam is an annual programming competition held since 2013. Contestants create ComputerCraft programs during the event, and usually stream their progress live. After the contest, a panel of judges grades the programs and medals are awarded. The programs made are free to use; some CCJam entries are still in use today!

Who can enter?

Anybody can participate - there are no restrictions. Players of all skill levels can enroll, and you don't need a Minecraft account. Disqualification or failure to submit an entry in a previous CCJam does not prevent you from enrolling in a future CCJam.

What does the winner get?

The top three programs are awarded gold, silver and bronze medals. CCJam gold medals are the highest honor given by any organization in the ComputerCraft community. Medalists also receive special honors and privileges on various ComputerCraft servers - and Krist prize money!

How is the winner chosen?

A panel of judges awards points to all submissions based on certain criteria. In recent CCJams, judges have been community members of very high standing and notability. The points assigned by each judge are averaged together to score a program. The medals are awarded from there, to the top three eligible programs.

Special thanks to the following for making CCJam possible:
kboy101222 • Csstform • ardera

CCJam rules and practices


Interested parties may enroll for a future or ongoing event at any time after the event is announced, and before submissions are closed. Enrollments are handled via one of three methods - a post to the event's thread, a private message to the thread poster, or an email to ccjam@ceriat.net.


Enrolled participants may withdraw from a future or ongoing event at any time. Withdrawn participants may re-enroll in the same event if they were not disqualified, and if the event is still ongoing. Submissions may not be withdrawn after they are posted.


Participants may submit their entries to the event at any time before the event ends. The submission must have been created during the event. APIs and libraries are allowed if they were approved by the judges and published to Reddit or the ComputerCraft forums on or before the day of the event's announcement. The submissions must be ComputerCraft programs. Use or requirement of third-party peripherals or command computers is allowed. If a third-party peripheral is required, it must have been publicly released on or before the day of the event's announcement. The submission may be in any programming language, as long as a Lua interpreter for that language has been publicly released on or before the day of the event's announcement. Each participant may have multiple entries, but can submit only one.

Usage of the HTTP API is allowed, but any code ran on a webserver must be made available to the judges. To be eligible to receive a medal, it must also be open source. Malicious programs are allowed too, but they are ineligible to receive medals. Malice is determined on a case-by-case basis. Physically dangerous programs are not considered malicious.


All submissions will be ran and judged by all judges on the event's panel. Judges may not make submissions in an event they will be judging. The panel consists of four judges, each appointed by the event. Each judge will assign points to each program based on several categories. A program's score is the mean of the points that it has received from each of the judges. Each judge may assign between 0 and 33 points to each submission. Scores may not be modified after they have been placed.

The scores placed reflect five categories of varying value, including Creativity (0-3 pts), Design (0-6 pts) and Speed (0-4 pts). Games are also scored based on Fun (0-10 pts). Programs that are not games are instead rated based on Usefulness (0-10 pts). A fifth category, Functionality (0-10 pts), represents how stable the program is against bugs. The score given for Functionality may not be higher than the program's score for Usefulness/Fun.


The top three highest-scoring submissions will earn gold, silver and bronze medals, respectively. Disqualified, withdrawn, malicious, or unsubmitted entries are not eligible to receive medals. If two or more submissions receive equal scores, and are tied for one of the top three positions, they will both receive the same grade of medal. There will always be at least one of each grade of medal assigned, unless there are less than three unique eligible scores, in which case only the gold medal will be awarded. No medals will be assigned if less than two submissions were made by the end of the event. Medals assigned after April 2, 2016 will be accompanied by a Krist reward depending on their grade. Gold medals are worth 10,000 KST, silver medals are worth 2,500 KST, and bronze medals are worth 500 KST. Krist payments will be organized after the event. Medals may be retroactively assigned or revoked if the scores of past events are found to be incomplete - Krist payments cannot be retroactively assigned or revoked.