This book was started in 2010 using a Dual processor Mac 550 MHz PowerPC running Mac OSX 10.5. Current revisions are now done on MacBook Pro (Intel) running MacOS 10.12.1 at 2.5GHz. It was originally done using Fossil version 1.27 and now revisions to the book are using Fossil 1.36. Because of this some of the pictures here will look slightly different in your copy of Fossil but the maintainers have been careful to update the esthetics but not the functions of the various pages. So you will see different, better looking pages but the functions will be the same.
In November 2020, Fossil is up to version 2.14 and there have been extensive changes to the command set, so documentation is longer but follows the same pattern as in earlier versions. Edits now being done on Debian Linux x64 running on an Intel J1900 cpu at 2GHz with 4 processors and 4 GB RAM. Could be done on a Raspberry Pi or Chromebook.