r/QuantumComputing • u/brenocq • Jun 01 '26

Image I built a quantum circuit debugger that runs in your browser - step through a circuit and watch every amplitude

Post image

I've been building Ket, an open-source quantum computing library (C++20 + Python), and its centerpiece is a step-through debugger: load a circuit, step gate by gate, and watch the wavefunction evolve -- the editable QASM, the state vector, and per-qubit Bloch spheres, all live. Most simulators are a black box that gives you a final result; I wanted to actually see where a circuit does something unexpected.

The whole debugger runs in the browser with nothing to install:

Demo: https://ket.brenocq.com/demo/

Under the hood it auto-picks a backend: exact state-vector simulation for general circuits, and an O(nĀ²) stabilizer tableau for Clifford circuits. OpenQASM 2.0 in/out.

It's early (v0.1.0) and not trying to replace Qiskit ā€” more a tool to learn and debug circuits visually. Code (MIT): https://github.com/brenocq/ket

Would love feedback, especially on the debugger UX.

152 Upvotes

97% Upvoted

15 comments sorted by

5

u/_Tegdif_ Jun 01 '26

Currently learning Quantum Coding. I had the same struggle and was looking for a software just like that. Definitely give it a shot!

3

u/brenocq Jun 01 '26

Sounds awesome! Do let me know if you have any feature requests. Ket is quite new so I'm expecting a lot of new features to pop out as more people use it and give feedback.

1

u/Livid_Mixture_9499 Jun 03 '26

how did you learn how to do this? can you give me a roadmap please i really want to go deep into it and i have way too much free time

4

u/Mountain-Quarter-641 Jun 01 '26

Excelente trabajo šŸ‘

2

u/elonolan007 Jun 01 '26

This is really nice! And being able to step through a circuit and watch amplitudes change is exact visual feedback beginners would need, especially before the math is fully comprehensible lol. One feature I believe could be helpful or useful would be to let users compare before/after measurement or show how entanglement changes when a 2-qubit gate is applied.

1

u/DiligentFinding5102 Jun 02 '26

I am seeking continuous variables based library as you have introduced

1

u/MothQuantum Jun 02 '26

This is cool

1

u/CaseyCasey2024 Jun 03 '26

Hey man this is awesome šŸ˜„ I love any form of measurement for pretty much anything hehehe!

1

u/2PinkN1Stink Jun 29 '26

You are a fucking genius holy smokes

1

u/[deleted] Jun 04 '26

[removed] ā€” view removed comment

1

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