What are my options for *computing symbolic results for quantum circuits*?

I have identified some possibilities:

* [SymPy][1] (see also [this][2]), unfortunately, the software forces you to encode the matrix of each gate explicitly instead of working with circuits;
* [IBM Qiskit v0.25 operator framework][3], which claims 
  > Qiskit operators fully support parameterization

  even if it seems not completely true since the same error of [this older question][4] holds and [this issue][5] is still open.


  [1]: https://docs.sympy.org/latest/modules/physics/quantum/index.html
  [2]: https://quantumcomputing.stackexchange.com/questions/9984/symbolic-quantum-computing-using-sympy-how-to-use-arbitrary-gate
  [3]: https://qiskit.org/documentation/tutorials/operators/01_operator_flow.html
  [4]: https://quantumcomputing.stackexchange.com/questions/14867/creating-a-parameterized-operator-in-qiskit
  [5]: https://github.com/Qiskit/qiskit-terra/issues/4751