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QubiStack is a quantum computing software company building high-performance quantum circuit simulation for researchers. Develop quantum algorithms today, without waiting on hardware.

Founded 2025HPC × Quantum
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QXel

The quantum simulator built for HPC.

QXel is our high-performance, GPU-accelerated quantum circuit simulator. Secondary-storage offloading pushes a single node to 42 qubits, CUDA and cuQuantum kernels drive throughput, and MPI scales it across a cluster. It all runs behind the Braket, Qiskit, and PennyLane SDKs you already use.

  • 42-qubit single node via secondary-storage offloading
  • CUDA & cuQuantum GPU kernels
  • MPI distributed, multi-node simulation
Learn moreRead the docs
ghz.py
from braket.devices import LocalSimulator
from braket.circuits import Circuit

# 3-qubit GHZ state
circuit = Circuit().h(0).cnot(0, 1).cnot(1, 2)
circuit.probability()

# Run on QXel: GPU-accelerated, storage-offloaded
qxel = LocalSimulator(backend="QXel-sv")
result = qxel.run(
    circuit,
    shots=4096,
    compute_type="cuda",
    offload_type="storage",
).result()

print(result.values)