CanaryCatch a quantum cloud that cheats.

Catch a quantum cloud
that cheats.

Quantum computers are powerful, but you can't check their answers. Canary hides known-answer tasks (traps) in your job and spots when a quantum cloud cuts corners, skips work, or makes things up.

Built with Qiskit. Runs on the machine you pick:
a simulator, an IBM noise model, or IonQ.

02 / The problem

You can't check a quantum computer's answer.

Quantum computers are powerful, but they run in the cloud. Your normal computer can't simply redo the work to verify the answer, so you have to trust the cloud.

Your computerPrepares the job and sends it to a quantum cloud.
Quantum cloudRuns the job and returns an answer.
The problemYou can't check if the answer is actually correct.

A cloud you don't control.

The quantum computer lives in someone else's data centre. They could use a cheaper machine, skip work, or return made-up results.

No easy way to verify.

Normal computers can't repeat the work of a quantum computer. That's the whole point of one, so you can't double-check the answer.

Small errors, real costs.

A wrong answer feeding a drug candidate, a material or a risk number is a costly decision made on bad data.

03 / The solution

Hide known answers and let Canary find out.

You hide small trap tasks inside your job. They look just like the real ones, but you already know the answer. If the cloud gets the traps wrong, Canary catches it and turns the results into a receipt.

  1. Add trapsHide tasks with known answers in your job.
  2. Send to the cloudRun the job on the quantum machine you pick.
  3. Check the trapsCanary compares the trap answers with the ones it knew.
  4. Get a receiptHow many of your answers you can trust, or that the cloud was caught.

Your job

trap (known answer)real task
Quantum cloud

Receipt

At least 83% right95% confidence
Alive traps
20
Dead traps
0
Real tasks
30

An honest run with 20 traps.

One circuit, as the server sees it

Traps and real tasks have the same shape and the same gates, so the cloud can't tell them apart.


      

    

  


  

    

      

        
04 / Proof

        
The receipt held.

        

        
A 95% receipt should hold at least 95% of the time.

      

      
Dead traps track wrong answersAs a machine gets worse, its traps die at the same rate its real answers go wrong. That's why the receipt works.

      

        
Test coverage

        

      

    

  


  

    

      

        
05 / What Canary isn't

        
Spot-checking, not full verification.

        
A clever cloud could, in theory, read a circuit's gate angles and recognise the traps. Canary gives you evidence about a cloud's reliability, not a guarantee that every single quantum answer is correct.

      

      

        
The limitation
A smart cloud could spot the traps.
Trap angles are multiples of π/2. Hiding them for real takes blind quantum computing. The console shows a smart cheater beating weak traps.

        
The real value
Evidence, not a guarantee.
A receipt with a stated confidence, tested against four kinds of cheating cloud. Far better than taking the cloud's word for it.

      

    

    

      
Ready to see it work?
Open the console
Hide traps, pick a cheater, and see who gets caught.