Quantum computing, for working developers.
The tutorials IBM and Microsoft won't write — opinionated, code-first, and written for engineers who learn by shipping. From your first qubit to post-quantum cryptography.
What vendor blogs won't publish
Independent benchmarks, honest comparisons, and tooling — all in places where IBM, Google, and Quantinuum have a structural conflict of interest.
Independent benchmark
Hardware Honesty Tracker
Every major quantum computer side-by-side. Qubit counts, gate errors, coherence, sourced from primary calibration data — not press releases.
Honest benchmarks
QML Reality Check
Pre-registered benchmarks of named QML methods vs strong classical baselines on real datasets. We publish whichever direction the numbers point.
Open-source tool
pqc-audit scanner
MIT-licensed CLI + browser tool that flags every quantum-vulnerable cryptographic primitive in your codebase, with concrete migration targets.
Latest tutorials
All tutorials →What Is a Qubit? From Classical Bits to Quantum States
A ground-up introduction to qubits for developers who already know code. Bloch sphere, Dirac notation, the normalization constraint, and why a qubit is not just a probabilistic bit — with runnable Qiskit code.
Superposition, Measurement, and the Born Rule
Measurement turns amplitudes into probabilities and destroys superposition. This tutorial walks through the Born rule, measurement in different bases, the no-cloning theorem, and why you can't just peek at a qubit without breaking it — with runnable Qiskit code.
Multi-Qubit Systems and Entanglement
Tensor products, the 2ⁿ-dimensional state space, separable vs entangled states, the four Bell states, and why entanglement is the real secret ingredient of quantum computing. With runnable Qiskit code and a measurement-correlation experiment.
Unitary Operators and the Universal Gate Set
Quantum gates are unitary matrices — reversible, norm-preserving operations on state vectors. This tutorial proves why, derives the universal {H, T, CNOT} set, and shows why any quantum computation decomposes into these primitives. With full Qiskit verification.
Pauli, Phase, and Rotation Gates
Every single-qubit gate is a rotation of the Bloch sphere. This tutorial derives the Pauli matrices, the phase gates (S, T), and the continuous Rx/Ry/Rz rotation family — and shows how to decompose any single-qubit unitary into three Euler-angle rotations. With visualizations and Qiskit verification.
Multi-Qubit Gates: CNOT, CZ, SWAP, Toffoli, and Controlled Everything
CNOT is the workhorse of entanglement, but the two-qubit gate zoo is richer than that. This tutorial walks through CZ, SWAP, iSWAP, Toffoli, and arbitrary controlled unitaries — plus the decomposition theorems that turn them all into CNOT + single-qubit primitives for real hardware.