Dyber SDK

Interact with the H-cat photonic quantum computer. Write a circuit once and run it on the local simulator today and on the H-cat QPU later, with no change to your code. This is the control interface, designed so that when the hardware exists, only the backend transport changes.

30-second quickstart

pip install dyber

from dyber import Dyber, Circuit
c = Circuit(2, "bell")
c.h(0); c.cx(0, 1); c.measure_all()
job = Dyber().backend("local_simulator").run(c, shots=1000)
print(job.result().counts())        # {'00': ~500, '11': ~500}

Five lines, a Bell state. Qubit 0 is the leftmost bit in result strings.

Three access modes

Same circuits, same job protocol, pick the surface that fits your workflow.

1. Python SDK

from dyber import Dyber, Circuit

dy = Dyber()
print(dy.backends())                 # local_simulator (online), hcat_qpu (offline)

c = Circuit(2, "bell")
c.h(0); c.cx(0, 1); c.measure_all()

res = dy.backend("local_simulator").run(c, shots=1000, loss_per_cycle=0.005).result()
print(res.counts())                  # measurement counts
print(res.resources)                 # code distance, cats per logical, hw modes per logical
print(res.noise)                     # physics-informed noise summary

2. Command line

The dyber command ships with the package (or use python -m dyber.cli):

dyber run bell.qasm --shots 1000     # run an OpenQASM file on the simulator
dyber run bell.qasm --json           # machine-readable output for scripts
dyber backends                       # list backends and their status
dyber examples                       # bundled example circuits to get started
dyber serve                          # start the reference control plane (REST API)
dyber version

3. REST API

Start the reference control plane and submit jobs over HTTP. This is the exact protocol the hardware control system will implement, documented in PROTOCOL.md.

dyber serve      # listens on http://127.0.0.1:8787

curl -s -X POST http://127.0.0.1:8787/jobs \
  -H "Content-Type: application/json" \
  -d '{"qasm": "OPENQASM 3.0; qubit[2] q; h q[0]; cx q[0], q[1];", "shots": 1000}'

Then GET /jobs/{id}/result returns counts plus the resource and noise reports. Jobs can also be submitted as circuit JSON ({"program": {...}}, see PROTOCOL.md). The hcat_qpu backend speaks this same protocol to the production control plane; the moment the hardware is online, dy.backend("hcat_qpu").run(c) runs on silicon.

Bring your own language

Dyber deliberately has no proprietary circuit language. Circuits come in and out through open formats and the tools you already use:

• OpenQASM 3 import and export: dyber.qasm.loads(text) and dyber.qasm.dumps(circuit). OpenQASM 2 programs are accepted on import.
• Qiskit adapter: dyber.interop.from_qiskit(qc) and to_qiskit(circuit) convert to and from a Qiskit QuantumCircuit.
• Cirq adapter: dyber.interop.from_cirq(circuit) and to_cirq(circuit) convert to and from a Cirq Circuit.

If your circuit already exists somewhere, it runs here. The adapters are duck-typed: neither Qiskit nor Cirq is a dependency of this package.

Examples

What the simulator is (and is not)

The local_simulator backend is an exact statevector simulator for up to 14 qubits, with physics-informed noise calibrated by the published H-cat resource model (June 2026 circuit-level validation: corrected loss threshold 0.79 percent per cycle, spec operating point 0.5 percent per cycle). Noise is a planning-grade estimate, applied as logical error rates and heralded-erasure fractions from that model; it is not a full physical simulation of the hardware. At or above the loss threshold the resource report honestly returns the above-threshold regime (no fault-tolerant distance) with a NISQ fallback estimate. The hcat_qpu backend points at the production control plane and is not yet available; until then, everything you write against the simulator carries over unchanged.

How it is layered

Development

pip install -e .[dev]        # from sdk/
python -m pytest tests -q

Proprietary components (the OpenForge compiler passes and calibration) are not part of this SDK; the native lowering here is illustrative. License: Apache-2.0.