diff --git a/pyproject.toml b/pyproject.toml
index 02c3222..7707b59 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -26,11 +26,11 @@ dependencies = []
 
 [project.optional-dependencies]
 openai   = ["openai~=1.30"]
-chroma   = ["chromadb~=0.4"]
+chroma   = ["chromadb>=0.4,<2.0"]
 sentence = ["sentence-transformers~=2.6"]
 serve    = ["fastapi~=0.110", "uvicorn~=0.27"]
 dev      = ["pytest~=8.0", "coverage~=7.0", "ruff~=0.5"]
-all      = ["openai~=1.30", "chromadb~=0.4", "sentence-transformers~=2.6", "fastapi~=0.110", "uvicorn~=0.27"]
+all      = ["openai~=1.30", "chromadb>=0.4,<2.0", "sentence-transformers~=2.6", "fastapi~=0.110", "uvicorn~=0.27"]
 
 [project.urls]
 Homepage       = "https://github.com/smartfind/loop-memory"