IBM released Qiskit's C API on October 6, 2026, saying it allows quantum circuits to be built and run natively in Fortran, C++, and Julia—no Python required. It is the company's first major software update since Qiskit v2.0, which introduced a unified C interface.
IBM reported that the C API connects Qiskit's high-performance Rust core to nearly every programming language used in high-performance computing and scientific computing. That compares with the Python SDK, which has been the primary entry point for most users.
The Qiskit C API is built on the Rust core and targets hybrid quantum-classical workflows in fields like optimization, machine learning, and scientific simulation. Availability begins with the release of Qiskit v2.0, initially for researchers and developers.
"Quantum computing will be a revolutionary paradigm for scientific computing," said Jim Garrison, IBM Research. "We believe integrating Qiskit into existing workflows is crucial for advancing the field.
The announcement follows recent demonstrations from IBM and its partners showing how quantum computing delivers its advantage in combination with classical resources. IBM did not say how widely the C API will be adopted, and noted that further exploration is needed to understand its impact on HPC communities.
Source: ibm
