There are several differences between the premium support that Pressbooks provides its clients and the opensource version.
Availability of themes-
In Pressbooks, a theme is the look and feel of a book. All Pressbook themes are child-themes of Pressbook-book. Pressbook-book creates the visual interface on every site, and the child themes are often typography, how images look, what the chapter header looks like, and how the table of contents is structured.
There are a couple open source themes, notably McLuhan and Jacobs, which are my two go-tos. Hosted Networks get additional themes including Malala which is my favorite theme that I don’t have. All of the Pressbooks themes are listed at https://pressbooks.com/themes/
One of the trickiest things of setting up Pressbooks on your own are the dependencies that you have to install. These are listed on the installation page, but one of the biggest ones that isn’t open source is “PrinceXML” or the cloud version of PrinceXML that is called “DocRaptor.” Subscription for PrinceXML is somewhere around $1,000 per server, but there is a nice noncommercial license that is available to use if you are providing the generated PDFs free of cost. You would have to review PrinceXML’s nomcommercial license and make sure that you feel that you fall under their free noncommercial license.
MathJax may be the most difficult dependency to run on your own, and there are currently instructions on github on how to run a microservice on your pressbooks server or on Amazon Lambda. Currently the microservice option relies on out of support versions of NodeJS and may not be appropriate if you are concerned with the security of using an EOL product on a production server.
LMS Integration and LTI
One of the premium plugins that Pressbooks “holds back” from the open source community is the LTI plugin, which allows deep connection between a university LMS and a pressbooks network, including returning grades for embedded H5P activities.
So in my estimation… what can open source Pressbooks do:
- Export PDFs, EPUBs, MOBI (You get the best PDFs by installing PrinceXML which you may qualify for the noncommercial license)
- You can install opensource plugins that lots of Pressbooks Networks use including H5P, TablePress, Hypothes.is, and Koko Analytics.
- You can connect to SSO
What do you get from purchasing Pressbooks from the Pressbooks team:
- Priority support from the developers of the application
- More themes and styles for your books
- LTI connection to the LMS including grade passback of H5P activities
- Accessible Math using MathJax rendered math across all versions (you can always use MathJax on the HTML versions of the book, and you can use a plugin called QuickLatex to render math in your exports, but there are accessibility implications.)
There are quite a few open source users like myself that try to contribute to the forums and support people who are trying Pressbooks using the open source method. I was helped so much by the community and do try to give back, but the support you get from volunteers like me is quite different from the ready to go option of Pressbooks. Most of the Pressbooks experts around the country seem to be in higher ed, and I don’t really see agencies or consultants that do Pressbooks work. Once in a while I see a job listing targetting a librarian or Pressbooks expert that may have a little extra capacity, but its not like WordPress that has agencies and individuals devoted to it.