v0.4.0 — Active Calibration & GRAPE-in-Rust

Open-Source Quantum Control Kernel

Pulse optimization and hardware abstraction for quantum computing research. GRAPE optimizer, multi-qubit scheduling, symplectic Clifford benchmarking.

from qubitos.pulsegen import generate_pulse

# Optimize a 2-qubit CZ gate pulse
result = generate_pulse(
    gate="CZ",
    num_qubits=2,
    duration_ns=80,
    target_fidelity=0.999,
)
print(f"Fidelity: {result.fidelity:.4f}")  # → 0.9983
1,215
Tests passing
92%
Code coverage
n≤5
Qubit GRAPE
99%+
Gate fidelity

Three Repositories, One System

qubit-os-core

GRAPE pulse optimization, pulse scheduling, calibration management, error budgets, Clifford benchmarking, and CLI tooling.

Python

qubit-os-hardware

Hardware Abstraction Layer — unified gRPC interface to quantum backends (QuTiP simulator, IQM Garnet, future hardware).

Rust

qubit-os-proto

Protocol Buffer definitions for all IPC — pulse envelopes, measurement results, calibration data, error budgets.

Protobuf

Core Capabilities

🎯 GRAPE Optimizer

Multi-qubit gradient ascent pulse engineering with per-qubit envelopes, dimension-scaled learning rates, and ZZ coupling drift Hamiltonians.

📅 Pulse Scheduler

ASAP scheduling with topological sort, constraint system (sequential, simultaneous, aligned), crosstalk avoidance, AWG grid alignment.

📊 Error Budgets

Cumulative error tracking across sequences — gate infidelity, T1/T2 decoherence, leakage, crosstalk, readout errors with fidelity prediction.

🔬 Benchmarking

Single and multi-qubit randomized benchmarking with symplectic Clifford tableaux, RB decay fitting, error-per-Clifford extraction.

⚙️ Parametric Gates

Google fSim(θ,φ) family and IBM cross-resonance gates with full parameterization for hardware-native gate sets.

🔒 Provenance

Merkle tree experiment tracking with content-addressed storage, automatic diffing, and reproducibility verification.

Architecture

Layered design separating physics from hardware

┌──────────────────────────────────────────────────┐
│                  User Layer                      │
│    CLI  ·  Python API  ·  Jupyter Notebooks      │
└──────────────────────┬───────────────────────────┘
                       │
┌──────────────────────▼───────────────────────────┐
│               qubit-os-core                      │
│  Pulse Gen · Scheduler · Calibrator · Provenance │
│  Error Budget · Benchmarking · Validation        │
└──────────────────────┬───────────────────────────┘
                       │ protobuf
┌──────────────────────▼───────────────────────────┐
│             qubit-os-hardware                    │
│           HAL Server (Rust + gRPC)               │
│    QuTiP Sim  ·  IQM Garnet  ·  Future HW       │
└──────────────────────────────────────────────────┘