diff --git a/.readthedocs.yml b/.readthedocs.yml
index 30684052..ef3c4b0c 100644
--- a/.readthedocs.yml
+++ b/.readthedocs.yml
@@ -8,8 +8,6 @@ build:
   os: ubuntu-22.04
   tools:
     python: "3.11"
-  apt_packages:
-  - graphviz
 
 python:
   install:
diff --git a/doc/requirements.txt b/doc/requirements.txt
index 3e760c81..de3ed4e8 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -7,6 +7,7 @@ sphinx
 sphinx_book_theme
 sphinxcontrib-bibtex
 myst-parser  # recommark is deprecated, https://stackoverflow.com/a/71660856/13573820
+graphviz
 
 pypsa
 powerplantmatching>=0.5.5