QuTip: Quantum Toolbox for simulating the dynamics of quantum systems.
Qiskit: IBM’s development kit, the indisputable standard for gate-based quantum software development.
Ocean SDK: D-Wave proprietary SDK. Really useful for problem posing and creating the first instances of our particular instances before moving to annealers, gate-based devices or whatever might be the final solver.
QuEra’s Bloqade for simulating Neutral Atom platforms both in Julia and Python
Amazon Braket for simulation and sending jobs to Amazon Braket service.
Pennylane SDK for Quantum Machine Learning, among other topics.
QUIMB for those wanting to get deep into Tensor Network stuff.