Read the Docs offers some additional flag settings which can be only be configured by the site admin. These are optional settings and you might not need it for every project. By default, these flags are disabled for every project. A separate request can be made by contacting us via email to enable or disable one or more of these featured flags for a particular project.
PIP_ALWAYS_UPGRADE: Always run pip install –upgrade
UPDATE_CONDA_STARTUP: Upgrade conda before creating the environment
The version of
conda used in the build process could not be the latest one.
This is because we use Miniconda, which its release process is a little more slow than
In case you prefer to use the latest
conda version available, this is the flag you need.
CONDA_APPEND_CORE_REQUIREMENTS: Append Read the Docs core requirements to environment.yml file
Makes Read the Docs to install all the requirements at once on
conda create step.
This helps users to pin dependencies on conda and to improve build time.
CONDA_USES_MAMBA: Uses mamba binary instead of conda to create the environment
conda solver consumes 1Gb minimum when installing any package using
This seems to be a known issue due conda forge has so many packages on it, among others.
Using this feature flag allows you to use mamba instead of
conda to create the environment
and install the dependencies.
mamba is a drop-in replacement for conda that it’s much faster and also
reduces considerably the amount of memory required to solve the dependencies.
DONT_OVERWRITE_SPHINX_CONTEXT: Do not overwrite context vars in conf.py with Read the Docs context
DONT_SHALLOW_CLONE: Do not shallow clone when cloning git repos
DONT_SHALLOW_CLONE flag is useful if your code accesses old commits during docs build,
e.g. python-reno release notes manager is known to do that
(error message line would probably include one of old Git commit id’s).
USE_TESTING_BUILD_IMAGE: Use Docker image labelled as `testing` to build the docs
LIST_PACKAGES_INSTALLED_ENV: List packages installed in the environment (“pip list” or “conda list”) on build’s output
DONT_CREATE_INDEX: Do not create index.md or README.rst if the project does not have one.
When Read the Docs detects that your project doesn’t have an
it auto-generate one for you with instructions about how to proceed.
In case you are using a static HTML page as index or an generated index from code, this behavior could be a problem. With this feature flag you can disable that.