ImportError: zstd C API versions mismatch

While running jupyter notebook #3 Vectorstores and Embeddings, while running this line:

“vectordb = Chroma.from_documents(
persist_directory= persist_directory

with: persist_directory = “/docs/chroma/”

it fails showing this error:

“ImportError: zstd C API versions mismatch; Python bindings were not compiled/linked against expected zstd version (10505 returned by the lib, 10502 hardcoded in zstd headers, 10502 hardcoded in the cext)”

I cannot find a solution for it.

I am running jupyter notebook in my Windows PC with Anaconda

  • I have updated Anaconda and conda
  • I have installed ztstandard and zstd using conda in my environment
  • I have used: !pip install zstandard --install-option=“–legacy”
  • I have used: !pip install zstd --install-option=“–legacy”

But error persists.

It reports:
“Unable to connect optimized C data functions [No module named ‘clickhouse_connect.driverc.buffer’], falling back to pure Python”

And is produced when chromadb / clickhouse_connet is trying to import ztstandard, and the same error pops out when I try to run a line with “import ztstandard”

I hope any from this community can help me to resolve this problem

Thanks in advance.


I was able to reproduce some of the examples using FAISS instead of Chroma, but of course having the database in RAM is not the same that having it in a disk repository.

I hope someone have a solution to this problem.