Here are the /etc/bashrc amendments performed by the installer on macOS

The macOS system updater often rewrites /etc/bashrc which removes the stuff added by the Nix installer, and I have to go hunting for the code every time. So, for future reference, the installer adds these lines to the end of /etc/bashrc:

# Nix
if [ -e '/nix/var/nix/profiles/default/etc/profile.d/' ]; then
  . '/nix/var/nix/profiles/default/etc/profile.d/'
# End Nix
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