I commonly develop my own data reduction and analysis tools and provide them as open-source software packages for the astronomical community via github.
You can find my personal github account here: Github
Interactive modeling of astronomical spectra.
I have developed Sculptor as a high level API and Graphical User Interface around LMFIT tailored specifically for the analysis of astronomical spectra. This package is designed to facilitate reproducible scientific results and easy to inspect model fits in an open source framework.
At the heart of the Sculptor package is the Graphical User Interface, which offers interactive control to set up and combine multiple spectral models to fully fit the astronomical spectrum of choice.
A Python package for semi-automated reduction of astronomical spectroscopic data."PypeIt is designed to be used by both advanced spectroscopists with prior data reduction expertise and astronomers with no prior experience of data reduction. It is highly configurable and designed to be applied to any standard slit-imaging spectrograph, including long-slit, multi-slit, as well as cross-dispersed echelle spectra." - The PypeIt Developers
I am a co-developer of the PypeIt package integrating the LBT/LUCI spectrographs into their suite of instruments.