Entropica QEC Challenge Winners Announcement

We are honoured to announce the winners of the inaugural Entropica QEC Challenge (21 May – 4 June 2025)!

And first, a huge thank you to every participant who joined us in exploring the boundaries of quantum error correction. Your creativity, commitment, and deep technical insights made this challenge a true success. Submissions came in from across the globe, each reflecting a shared curiosity and passion.

This challenge was more than a competition. It was a collaborative learning experience for both our participants and us at Entropica. Your feedback provided us with valuable insights into how Entwine can better support the growing community of QEC practitioners. While this early version of Entwine had its limitations, your submissions demonstrated what can be achieved through creativity, determination, and intelligent design.

We were especially impressed by the ingenuity and clarity demonstrated by our top entries. These participants not only tackled all three tasks but also did so by creating functional and efficient lattice surgery circuits inside Entwine, pushing its capabilities to their limits.

And the Winners are:

1st Place – QEC Architect - S$1,500 Cash Prize

Tom Peham, Doctoral Student at the Technical University of Munich, Germany
Tom showed the masterful use of ZX calculus to simplify the circuits in task 2 and 3, and to obtain the lattice surgery circuit in a straightforward manner. In task 2, his circuit used 3 frames (timesteps in Entwine), and a total spatial footprint of 2 by 4 logical qubits. For task 3, his circuit used 6 frames and a total spatial footprint of 6 by 6 logical qubits. Amongst all submissions, Tom’s solutions had one of the smallest circuits, thus putting himself in the top spot.

2nd Place – QEC Artisan - S$1,000 Cash Prize

Aristomenis Zazanis, Prospective Doctoral Student, United Kingdom
Aristomenis saw that the circuit in task 2 could be much simplified by looking at the output state. His solution in task 2 had a total spatial footprint of 4 by 4 logical qubits, and used 21 timesteps to achieve the final state. The relatively high timestep-count was due to the direct translation of logical CNOT gates into lattice surgery sequences, not seeing that a part of the circuit was simply a logical 4-qubit GHZ state, which could have been created in a simpler way. In task 3, his solution had a total spatial footprint of 7 by 7 logical qubits and used 17 frames. His solution leveraged on parallelising lattice surgery actions into the same frame, while still ensuring that “clashes” do not occur.

3rd Place – QEC Explorer - S$500 Cash Prize

Davide Laureti, Student, Italy
Davide explained his thought process clearly and gave a detailed breakdown of the resources consumed by these lattice surgery circuits for the tasks. He translated all the logical gates directly into lattice surgery sequences. In task 2, his circuit used 41 frames, and a total spatial footprint of 7 by 7 logical qubits. In task 3, his circuit used 104 frames, and a total spatial footprint of 2 by 10 logical qubits. While Davide’s solution had one of the largest resource consumption amongst all submissions, his circuits were correct. For task 3, by recognising that the patches for the 9 data qubits of the surfaces could be placed in a line to facilitate the lattice surgery sequences for the logical CNOT gates, he was able to cut down some of qubit usage.

Honourable Mention: Tim Chan, Quantum Computing DPhil Student, United Kingdom
Tim had the best solution for Task 2. He implemented the algorithm in arXiv:2401.15829, creating a solution that could, in-principle, solve any logical Clifford circuit. His implemented code found a solution that used 3 frames (!) but had a total spatial footprint of 6 by 6 logical qubits. Tim was also able to find a good plan of action for Task 3, but was unable to make it work in Entwine.

To everyone who took part, thank you. You made this challenge an energising and inspiring experience. We are excited about what comes next for Entwine and for the future of QEC.

Interested in staying involved or learning what’s coming next?
Reach us anytime at [email protected].

Let’s keep building the future of fault-tolerant quantum computing together.

Building the Software Stack for Fault-Tolerant Quantum Error Correction

Entwine is a visual IDE built to simplify the development and exploration of topological quantum error correction (QEC) schemes. From logical state preparation to lattice surgery sequencing, Entwine provides an intuitive environment for designing, simulating, and comparing QEC circuits. Whether you are testing surface-code variants, visualising decoder behaviour, or sequencing error-corrected operations, Entwine helps you work at the level of systems, not just gates. It makes QEC workflows more transparent, programmable, and composable.

We have built Entwine to accelerate innovation in QEC. And now, we invite you to push it to its limits.

Welcome to the EL QEC

A global competition designed to bring together the next generation of fault-tolerance architects. At Entropica, our mission is to build the software stack for fault-tolerant quantum computing. This Challenge is our way to start opening that stack to the world.

As a participant, you will face a set of technical challenges and creative tasks based on real QEC problems. Your objective is to use Entwine to solve them. The Challenge is open to anyone, whether a student just starting their QEC journey, a seasoned researcher looking for better software solutions, or a developer curious about what comes after classical computing. This Challenge is for you.

Timeline

Prizes

• 1st Place – QEC Architect
  S$1,500 Cash Prize
  Fast-track interview opportunity with Entropica
  Spotlight feature on Entropica’s Medium page
  Premium Entropica swag kit

• 2nd Place – QEC Artisan
  S$1,000 Cash Prize
  Deep-dive session with Entropica’s Science Team
  Swag kit

• 3rd Place – QEC Explorer
  S$500 Cash Prize
  Community recognition
  Swag kit

How to Participate

1. Accept the Terms and Conditions and Sign up to use Entwine.
2. Access and use Entwine.
3. Complete the tasks using Entwine.
4. Submit your solutions by the deadline.

View Full Tasks and Scoring Criteria

Intro to Entwine Video

Entwine is powered by Entropica Loom under the hood, it is a suite of visualisers and tools designed to simplify the creation, manipulation, and execution of fault-tolerant circuits. Entwine can be extended to multiple quantum hardware stacks with unique lattice structures and connectivity, while also being plug-and-play and opaque to the downstream quantum software developer. Entwine is the path of least resistance between having a QPU and using the QPU productively.

Key features:

• Powered by Loom, Entropica’s software to map logical to physical circuits.
• No installation required (runs in browser).
• Visual, extensible interface supporting different hardware stacks.
• Off-the-shelf integration with Stim and Crumble.

Tasks Overview

Participants will complete three technical tasks:

• Concatenated Repetition Code.
• Translate logical operations into lattice surgery.
• Compare concatenated vs surface code performance.

All tasks must be completed using Entwine.

Link to full details: View Full Tasks and Scoring Criteria

Terms & Conditions

By signing up, you agree to the full terms and conditions:

• View Full Terms
• Download PDF version

Contacts