  Scientific simulation codes are public property sustained by the community.
Modern technology allows anyone to join scientific software projects, from
anywhere, remotely via the internet.
  The phonopy and phono3py codes are widely used open source phonon calculation
codes. This review describes a collection of computational methods and
techniques as implemented in these codes and shows their implementation
strategies as a whole, aiming to be useful for the community. Some of the
techniques presented here are not limited to phonon calculations and may
therefore be useful in other area of condensed matter physics.
