When LISO (the tool my project is based on) was first made, SPICE simulators couldn't properly handle "realistic" op-amp parameters, like finite open loop gain,

When LISO (the tool my project is based on) was first made, SPICE simulators couldn't properly handle "realistic" op-amp parameters, like finite open loop gain, strange phase shifts due to output impedance especially of FET-based op-amps, realistic noise, stability of circuits containing feedback loops, etc. Furthermore, SPICE models provided by manufacturers typically don't represent the real behaviour of their op-amps, especially when it comes to noise, so the idea was to build a tool to which you can give arbitrary, perhaps measured, noise spectra. LISO also contains a brilliant fitting routine which can take a measured transfer function or noise spectrum and fit circuit parameters (e.g. op-amp noise, resistor values, etc.) to the data. It first uses some standard fitting algorithm (e.g. Nelder-Mead) to get close to the possible minimum, then uses a custom optimisation in log space to get the global minimum. If I remember correctly the author published a paper on this, and I can try to find it if someone is interested.