Qiskit 2.1 Boosts Performance, Updates C API, Drops Python 3.9 - Quantum Zeitgeist

The article delves into IBM's Qiskit v2.1 update, focusing on performance enhancement and increased compatibility, authored by IBM Quantum.

Qiskit's latest version accelerates quantum circuit optimization with a Rust-based code rewrite and introduces a new QPY file version. Developers must adapt due to complex number handling changes and deprecated QuantumCircuit subclasses. Key improvements include optimized Solovay-Kitaev decomposition and Sabre layout heuristics, alongside updates in the C API for complex number handling and bug fixes.

• Qiskit v2.1 enhances performance with Rust-based optimizations.
• New QPY file version requires 'qpy-compat' dependency for compatibility.
• Developers using deprecated QuantumCircuit subclasses have until v3.0 to migrate.
• Significant updates include complex number handling improvements in the C API.