Crossfire has file releases (i.e., 1.75.0), but also has ongoing updates using git revision control system.
The general commands to check out a module (archetypes, client, maps, server map editor, et al) is the following:
git clone https://git.code.sf.net/p/crossfire/crossfire-arch crossfire-crossfire-arch
git clone https://git.code.sf.net/p/crossfire/crossfire-client crossfire-crossfire-client
git clone https://git.code.sf.net/p/crossfire/crossfire-maps crossfire-crossfire-maps
git clone https://git.code.sf.net/p/crossfire/crossfire-server crossfire-crossfire-server
git clone https://git.code.sf.net/p/crossfire/crossfire-sounds crossfire-crossfire-sounds
git clone https://git.code.sf.net/p/crossfire/jxclient crossfire-jxclient
git clone https://git.code.sf.net/p/crossfire/metaserver crossfire-metaserver