- :py:mod:`pvlib.ivtools.sdm` is now a subpackage. (:issue:`2252`, :pull:`2256`)
- Add a function for estimating PVsyst SDM parameters from IEC 61853-1 matrix data (:py:func:`~pvlib.ivtools.sdm.fit_pvsyst_iec61853_sandia_2025`). (:issue:`2185`, :pull:`2429`)
- Add a supporting reference to :py:func:`pvlib.atmosphere.get_relative_airmass` (:issue:`2390`, :pull:`2424`)
- Documented how np.nan values are handled by :py:func:`~pvlib.spectrum.average_photon_energy` (:issue:`2423`, :pull:`2426`)
- Cliff Hansen (:ghuser:`cwhanse`)
- Rajiv Daxini (:ghuser:`RDaxini`)
- Kevin Anderson (:ghuser:`kandersolar`)