diff --git a/bench/requirements.txt b/bench/requirements.txt
index 6d8870e..9e630a2 100644
--- a/bench/requirements.txt
+++ b/bench/requirements.txt
@@ -2,5 +2,5 @@
 # are stdlib. Install torch first, CPU build, the same one the baseline was run with:
 #   pip install torch==2.4.1 --index-url https://download.pytorch.org/whl/cpu
 numpy>=1.24
-sentence-transformers==3.1.1
+sentence-transformers==3.4.1
 transformers==4.44.2
diff --git a/pyproject.toml b/pyproject.toml
index 26bd351..24c8a4f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -53,7 +53,7 @@ dependencies = ["numpy>=1.24"]
 # an x86_64 Mac, Python 3.12, fresh `pip install` from PyPI). sentence-transformers
 # 6.x in turn requires transformers 5.x, so both are capped there.
 embeddings = [
-  "sentence-transformers>=2.6",
+  "sentence-transformers<5",
   "numpy<2; sys_platform == 'darwin' and platform_machine == 'x86_64'",
   "transformers<4.50; sys_platform == 'darwin' and platform_machine == 'x86_64'",
   "sentence-transformers<5; sys_platform == 'darwin' and platform_machine == 'x86_64'",