qiskit-community/qiskit-ignis

Qiskit Ignis is a legacy project that has been officially deprecated and superseded by `qiskit-experiments`. While it was once a pillar of the Qiskit ecosystem (specifically the characterization and mitigation layer), its utility has transitioned to newer, more modular frameworks. The defensibility is low because the maintainers themselves (IBM/Qiskit community) have moved on to a superior internal architecture. The high fork-to-star ratio (158 forks to 169 stars) indicates that this was once critical infrastructure, but the zero velocity confirms it is now a ghost project. From a competitive standpoint, any project using Ignis today is accruing significant technical debt. The displacement risk is '6 months' because the displacement has already occurred in favor of qiskit-experiments and third-party mitigation libraries like Mitiq (Unitary Fund). This project represents the 'hardware-aware' software layer that is increasingly being integrated directly into cloud quantum platforms (IBM Quantum, Azure Quantum, AWS Braket) as managed services rather than standalone libraries.