readthedocs.org.requirements.txt

# readthedocs.org gives no way to change the install command to "pip
# install -e acme[docs]" (that would in turn install documentation
# dependencies), but it allows to specify a requirements.txt file at
# https://readthedocs.org/dashboard/letsencrypt/advanced/ (c.f. #259)

# Although ReadTheDocs certainly doesn't need to install the project
# in --editable mode (-e), just "pip install acme[docs]" does not work as
# expected and "pip install -e acme[docs]" must be used instead

-e acme[docs]