diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index 6abd87d..74b74a4 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -15,4 +15,4 @@ jobs:
       envs: |
         - linux: py310-test
         - macos: py311-test
-        - windows: py312-test
+        - windows: py312-test-astropydev
diff --git a/tox.ini b/tox.ini
index cda235e..b763645 100644
--- a/tox.ini
+++ b/tox.ini
@@ -6,8 +6,11 @@ isolated_build = true
 
 [testenv]
 changedir = .tmp/{envname}
+setenv =
+    astropydev: PIP_EXTRA_INDEX_URL = https://pypi.anaconda.org/liberfa/simple https://pypi.anaconda.org/astropy/simple
 deps =
-    git+https://github.com/astropy/astropy
+    !astropydev: astropy
+    astropydev: astropy>=0.0.dev0
 extras =
     test