SIPGI (2022MNRAS.514.2902G) is a software to reduce optical/near-infrared spectroscopic data acquired by slit-based spectrographs. The software provides a GUI written in Python, used to organise data, to run the reduction recipes (written in C) and to check reduction results with a set of interactive graphical tools. The interaction between Python and C is obtained using the SWIG wrapper.

SIPGI is a complete spectroscopic data reduction environment based on three key points:
1. the instrument model, i.e. the analytic description of the main calibration relations: spectra location, spectra tracing and wavelength calibration. This model can be easily checked and adjusted on data by using a graphical tool;
2. a built-in data organiser that classifies the data and, together with a graphical interface, helps in feeding the recipes with the correct inputs;
3. the design and flexibility of the reduction recipes; the number of tasks required to perform a complete reduction is minimised, while preserving the possibility of verifying the accuracy of the main stages of the data-reduction process.

This architecture allows SIPGI to retain the high level of flexibility and accuracy typical of the standard 'by-hand' reduction and, on the other side, to provide a higher level of efficiency.

The current version of SIPGI manages data from the MODS and LUCI spectrographs mounted at the Large Binocular Telescope. It is our plan to extend SIPGI to other through-slit spectrographs.