-The adventure.text file is no longer required at runtime. Instead, it
-is compiled at build time to a source module containing C structures,
-which is then linked to the advent binary.
-
-The game-save format has changed. This was done to simplify
-FORTRAN-derived code that formerly implemented these functions;
-without C's fread(3)/fwrite() and structs it was necessarily pretty
-ugly by modern standards. Encryption and checksumming have been
-discarded - it's pointless to try tamper-proofing saves when everyone
-has the source code.
+The adventure.text file is no longer required at runtime. Instead, an
+adventure.yaml file is compiled at build time to a source module
+containing C structures, which is then linked to the advent
+binary. The YAML is drastically easier to read and edit than
+the old ad-hoc format of adventure.txt.
+
+The game-save format has changed. This was done to simplify the
+FORTRAN-derived code that formerly implemented the save/restore
+functions; without C's fread(3)/fwrite() and structs it was
+necessarily pretty ugly by modern standards. Encryption and
+checksumming have been discarded - it's pointless to try
+tamper-proofing saves when everyone has the source code. However
+the game still integrity-checks savefiles on resume, including an
+abort if the endianness of the restoring machine does not match that of
+the saving machine. There is a magic-cookie header on the saves so
+in theory they could be identified by programs like file(1).
+
+Save and resume filenames are stripped of leading and trailing
+whitespace before processing.
+
+A -r command-line option has been added. When it is given (with a file
+path argument) it is functionally equivalent to a RESTORE command.
+
+An -a command-line option has been added (conditionally on
+ADVENT_AUTOSAVE) for use in BBS door systems. When this option is
+given, the game roads from the specified filename argument on startup
+and saves to it on quit or a received signal. There is a new nmessage
+to inform the user about this.
+
+The game can be built in a mode that entirely disables save/resume
+(-DADVENT_NOSAVE). If the game had been built this way, a diagnostic is
+emitted if you try to save or resume.