How a book is made
What is written here can be verified. Here is what does the verifying.
One book, one dedicated project
Each title in this house is entrusted to a project that does nothing else: the text, the progression, the exercises and their answers, the openly licensed illustrations that go with them, and the layout. A project never works on two books at once, and a book is never assembled out of pieces written for something else.
The floor is fifty pages. It is not there to pad the volume: below it, a textbook cannot carry a full progression with its exercises, and it becomes a worksheet again. A shorter text has a place at ODERSA, but not under the name of a book.

The stages, in order
- The go-ahead
A title is not opened without a decision of the association. The house works on one book at a time. - The writing
The course, the exercises and the answers, by one hand, all the way to the end of the contents. - The crossed check
A full reading by someone who did not write the text. It is an obligation, not an option, and it applies to every language published. - The colophon
The book receives its making record: who, when, with what, under which licence, and the caveat about mistakes. - The release
The book appears for reading online and for download, in every language built, on the same day.
Crossed checking, in practice
A reader does not fix punctuation: they look for mistakes. They follow the reasoning chapter by chapter, work the exercises using only what the book has already taught, and compare their results with the answers. An exercise that needs an idea introduced three chapters later is a progression error, and it is fixed before release.
What they find goes back to the author, with the page and the sentence. Two rounds are normal. A text that needs five is a text to rebuild from its outline, and the association would rather say so early.
The rule applies to translations, and that is where it is tempting to forget it: a translation proofread by its translator has not been proofread. A translator sees what they meant to write, not what they wrote.
The caveat every book carries
A textbook read twice can still contain a mistake. Denying it would be a disservice to the people learning from it. Every book from this house therefore carries a written caveat in its colophon: double checking reduces mistakes, it does not remove them.
ODERSA corrects what is reported, redates the book, and says what changed. Reporting has an address, that of the publishing team, at the foot of this page. A report that gives the page and the exact sentence is handled faster than a report saying there is a mistake somewhere.
What the machine refuses to publish
These refusals are not intentions: they are programs that stop the release, and each of them has already refused something.
- A number written by hand: every figure on this site is counted at build time, and the robots plan serves as a counter-count.
- A font, an image or a text whose licence is not traced back to its own source page.
- A font file declared in the catalogue but missing from disk, and the reverse: a file present on disk but missing from the catalogue.
- A font file that is not a font file, verified at its first bytes.
- An image declared as served whose files are not on disk, or whose text alternative is missing in a language.
- A colour pair below its contrast threshold, in each of the five display states this site serves.
- A colour that belongs to another site of the association, or a hue that comes too close to it in lightness and saturation.
- A dead internal link, an anchor that leads nowhere, a page without a title or without a description.
- A page that no other page cites, and an error page counted as a page of the site.
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