The Nazgul framework performs GRB localization via fitting non-parametric models to their data time-series and computing the the time delay between them. It is built on Stan (ascl:1801.003) and implements a parallel version of non-stationary Random Fourier Features. This avoids using heuristic methods, such as cross-correlation, which do not have a self-consistent statistical model. Satellites throughout the Sol system observe gamma-ray bursts at different times due to the finite speed of light, creating a time delay in their observed light curves. The time delay can be used to triangulate the gamma-ray burst position on the sky; these triangulations create annuli or rings on the sky. Nazgul searches for these annuli so that in the darkness, it can bind them to a location on the sky.

pynchrotron implements synchrotron emission from cooling electrons. It removes the need for GSL which was originally relied on for a quick computation of the synchrotron kernel. The code has been ported from GSL and written directly in python as well as accelerated with numba. pynchrotron also includes an astromodels (ascl:2506.019) function for direct use in 3ML (ascl:2506.018).

Astromodels defines models for likelihood or Bayesian analysis of astrophysical data. Though designed for analysis in the spectral domain, it can also be used as a toolbox containing functions of any variable. Astromodels is not a modeling package; it provides the tools to build a model as complex as one needs. A separate package such as 3ML (ascl:2506.018) is needed to fit the model to the data.

Popsynth provides an abstract way to generate survey populations from arbitrary luminosity functions and redshift distributions. Additionally, auxiliary quantities can be sampled and stored. Populations can be saved and restored via an HDF5 files for later use, and population synthesis routines can be created via classes or structured YAML files. Users can construct their own classes for spatial, luminosity, and other distributions, all of which can be connected to arbitrarily complex selection functions.