diff --git a/conda.recipe/meta.yaml b/conda.recipe/meta.yaml
index d291439..49a755c 100644
--- a/conda.recipe/meta.yaml
+++ b/conda.recipe/meta.yaml
@@ -35,6 +35,7 @@ requirements:
     run_constrained:  # requirements of optional dependencies
         - bokeh <3.0  # Code not adapted to versions >=3.0 yet
         - selenium <4.3  # Required by bokeh<3.0, otherwise errors finding firefox
+        - numpy <2.0  # For compatibility with bokeh<3.0
 
 about:
     home: https://github.com/jnettels/trnpy