conda-forge-pinning is a python package that defines and imports conda-forge dependency pinnings.
cf_pinning/pinning.json defines the pins in a dictionary format. The key is the package name, the value can either be a version string or a list of two version strings. In the latter case, the first version string represents the build dependency, the second sets the run dependency.
"fontconfig":"2.12.*",
Pin fontconfig to version 2.12.* in both the build and the run dependency section.
"freetype": ["2.7", "2.7|2.7.*"]
Depend on freetype 2.7 in the build dependency section; pin the run dependency to an arbitrary patch version of freetype 2.7.