  Axions and axion-like particles (ALPs) are hypothetical particles that occur
in extensions of the Standard Model and are candidates for cold dark matter.
They could be detected through their oscillations into photons in the presence
of external electromagnetic fields. gammaALPs is an open-source python
framework that computes the oscillation probability between photons and
axions/ALPs. In addition to solving the photon-ALP equations of motion,
gammaALPs includes models for magnetic fields in different astrophysical
environments such as jets of active galactic nuclei, intra-cluster and
intergalactic media, and the Milky Way. Users are also able to easily
incorporate their own custom magnetic-field models. We review the basic
functionality and features of gammaALPs, which is heavily based on other
open-source scientific packages such as numpy and scipy. Although focused on
gamma-ray energies, gammaALPs can be easily extended to arbitrary photon
energies.
