Keep Building Docs With Old Version Of MkDocs

Recent changes to mkdocs forced us to upgrade the default version installed by Read the Docs and this may be a breaking change for your documentation.

You should check that your docs continue building in any of these cases:

  • your project doesn’t have a requirements.txt file pinning mkdocs to a specific version
  • your project is using a custom theme
  • your project is using Markdown extensions

In case your builds are failing because of a mkdocs issue, you may want to follow one of the following solutions depending on the case.

Pin mkdocs to the previous version

Before Read the Docs upgraded its default version installed, mkdocs==0.15.0 was used. To make your project continue using this version you will need to create a requirements.txt file with this content:

# requirements.txt


Most of the breaking changes where introduced in mkdocs==0.17, so you may want to test only pinning mkdocs to mkdocs<0.17 and check if your docs keep building successfully.

More detailed information about how to specify dependencies can be found here.

Upgrade your custom theme to be compatible with newer mkdocs versions

It is possible that event your build passes your documentation doesn’t look correct. This may be because the new mkdocs==0.17.3 version installed by Read the Docs introduced some breaking changes on the structure of the theme.

You should check the mkdocs’ Custom Theme documentation to upgrade your custom theme and make it compatible with the new version.

Upgrade how extension arguments are defined

mkdocs has changed the way that markdown_extensions are defined and you may need to upgrade it. If you where passing arguments to the extension by defining them between brackets (toc(permalink=true)) in your mkdocs.yaml you may need to upgrade it to the new way.

For example, this definition:

  - admonition
  - codehilite(guess_lang=false)
  - toc(permalink=true)
  - footnotes
  - meta

needs to be replaced by:

  - admonition
  - codehilite
      guess_lang: false
  - toc
      permalink: true
  - footnotes
  - meta