diff --git a/docs/environment.yml b/docs/environment.yml
index 06ffdb0da..879afc432 100644
--- a/docs/environment.yml
+++ b/docs/environment.yml
@@ -4,7 +4,9 @@ channels:
 - defaults
 dependencies:
 - python==3.5
+- sphinx==1.5.1
+- sphinx_rtd_theme==0.1.9
 - doxygen
 - pip
 - pip:
-  - https://github.com/michaeljones/breathe/archive/master.zip
+  - breathe