diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 20d77d37..1ad41cde 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -40,7 +40,7 @@ jobs:
 
     strategy:
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-latest, macos-latest, windows-latest]
     runs-on: ${{ matrix.os }}
 
     steps:
diff --git a/requirements/requirements.txt b/requirements/requirements.txt
index c1d11415..8dcb1923 100644
--- a/requirements/requirements.txt
+++ b/requirements/requirements.txt
@@ -3,8 +3,9 @@ setuptools>=40.8.0
 # until GPy is updated we need to avoid 1.24 or higher
 numpy>=1.23
 # This is unfortunate - we don't need matplotlib
-# but until GPy and GPyOpt get their dependencies straight
-# we need GPy's plotting extra to ensure smooth installation
-GPy[plotting]>=1.13.0
+# but until GPy gets its dependencies straight
+# we need matplotlib to ensure smooth installation
+matplotlib>=3.9
+GPy>=1.13.0
 emcee>=2.2.1
 scipy>=1.1.0