Create repodata.json for collections of conda packages.

conda install -c anaconda conda-index



conda index, formerly part of conda-build. Create repodata.json for collections of conda packages.

Run normally

python -m conda_index <path to channel directory>

Note conda index may find legacy conda-build index instead.

Run for debugging

python -m conda_index --verbose --threads=1 <path to channel directory>


conda create -n conda-index "python >=3.9" conda conda-build pip
# pip >=22 is required for pip install -e conda-index
pip install --upgrade pip # if pip < 22
# in a parent directory
git clone
pip install -e conda-index[test]

cd conda-index

Summary of changes from the previous conda-build index version

  • Approximately 2.2x faster conda package extraction, by extracting just the metadata to streams instead of extracting packages to a temporary directory; closes the package early if all metadata has been found.

  • No longer read existing repodata.json. Always load from cache.

  • Uses a sqlite metadata cache that is orders of magnitude faster than the old many-tiny-files cache.

  • The first time conda index runs, it will convert the existing file-based .cache to a sqlite3 database .cache/cache.db. This takes about ten minutes per subdir for conda-forge. (If this is interrupted, delete cache.db to start over, or packages will be re-extracted into the cache.) sqlite3 must be compiled with the JSON1 extension. JSON1 is built into SQLite by default as of SQLite version 3.38.0 (2022-02-22).

  • Each subdir osx-64, linux-64 etc. has its own cache.db; conda-forge’s 1.2T osx-64 subdir has a single 2.4GB cache.db. Storing the cache in fewer files saves time since there is a per-file wait to open each of the many tiny .json files in old-style .cache/.

  • cache.db is highly compressible, like the text metadata. 2.4G → zstd → 88M

  • No longer cache paths.json (only used to create post_install.json and not referenced later in the indexing process). Saves 90% disk space in .cache.

  • Updated Python and dependency requirements.

  • Mercilessly cull less-used features.

  • Format with black


This version of conda-index continues indexing packages from other subdirs while the main thread is writing a repodata.json.

All current_repodata.json are generated in parallel. This may use a lot of ram if repodata.json has tens of thousands of entries.