diff --git a/docs/environment.yml b/docs/environment.yml
index 0b751f5ac..c89fbf3c5 100644
--- a/docs/environment.yml
+++ b/docs/environment.yml
@@ -1,6 +1,7 @@
 name: nbclassic_docs
 channels:
   - conda-forge
+  - nodefaults
 dependencies:
 - python=3.8
 - pydata-sphinx-theme
diff --git a/readthedocs.yml b/readthedocs.yml
index 7bd34f0ae..a1a2b614d 100644
--- a/readthedocs.yml
+++ b/readthedocs.yml
@@ -6,7 +6,7 @@ build:
     python: "3.10"
 
 conda:
-  file: docs/environment.yml
+  environment: docs/environment.yml
 
 sphinx:
   configuration: docs/source/conf.py