CHFS is a file system developed at the Department of Software Engineering, University of Szeged, Hungary. It's the first open source Flash memory-specific file system written for the NetBSD operating system.
Similar to UBIFS, the CHFS file system utilizes a separate layer for handling Flash aging and bad blocks, called EBH (erase block handler). The file system itself is modelled after JFFS2, thus the internal structure is very similar.
CHFS was originally called ChewieFS during development. The name was changed to avoid legal issues and to have a more neutral name.