Hi Codeforces!
About seven weeks ago, AdhamAfterMidnight and I shared VoidHub, a project we started while preparing for the ECPC.
The main idea was simple: make regular practice feel less repetitive. Invite a friend, enter a live 1v1 room, solve under a timer, and let the original judge decide the result.
Since that post, we kept building, testing, and fixing plenty of details. This is a small update about what has changed. ## VoidHub is still about 1v1
The core of VoidHub is still live 1v1 competitive programming.
You can invite a friend, choose a mode, set a difficulty range and timer, then play in the same room using problems from:
- Codeforces
- HackerRank
- Online Judge
The available duel formats include BO3, BO5, Blitz, Pick & Play, and Quick Match links.
For Codeforces rooms, submissions are sent through the linked Codeforces account. If your solution gets Accepted, it appears normally in your Codeforces submissions and profile.
VoidHub is not trying to replace Codeforces or any original judge. It is simply a practice and duel layer around them.
Solo Sprint
We recently added a mode for practicing alone: Solo Sprint.
A Solo Sprint gives you ten VoidHub Original problems, ordered from easier to harder. The next problem stays locked until you solve the current one.
Every new sprint gets a fresh set, and problems you already solved do not appear again. You can also choose your own timer before starting.
VoidHub Originals
We started building a problemset made specifically for VoidHub.
These problems have full statements, samples, tags, time and memory limits, private tests, and in-platform judging. We are also adding a contribution flow where users can submit problem ideas for review.
The goal is to slowly build a problemset that feels native to the platform instead of only depending on external sources.
CPC Archive
We also added a separate CPC section.
It contains university contest problems from events such as ECPC, ACPC, and other regional contests. The problems are prepared inside the same VoidHub experience with statements, samples, limits, tags, and the compiler panel.
Profiles and progress
Profiles have also received a lot of work.
They now show rating progress, match history, recent submissions, solved problems, achievements, friends, and more. We wanted the site to remain useful even outside a single room.
Small but important fixes
A large part of the recent work was not very visible: judging flow, test handling, timers, statement rendering, room states, submission verdicts, and the small edge cases that appear when people actually use a website.
The Online Judge access and link issue from the previous version has also been resolved.
It is still a small project built by two people, and we are actively using it ourselves while practicing.
You can try it here:
Any feedback, bug report, or requested improvement can be sent in the comments. We read them all, especially feedback about the 1v1 experience, Solo Sprint, problem selection, and anything that feels annoying during practice.
Thanks for reading!
