diff --git a/tox.ini b/tox.ini
index 42cae19..94278da 100644
--- a/tox.ini
+++ b/tox.ini
@@ -10,7 +10,7 @@ envlist =
 passenv = HOME,WINDIR,CC,CI
 
 setenv =
-    devdeps: PIP_EXTRA_INDEX_URL = https://pypi.anaconda.org/astropy/simple https://pypi.anaconda.org/scientific-python-nightly-wheels/simple
+    devdeps: PIP_EXTRA_INDEX_URL = https://pypi.anaconda.org/astropy/simple https://pypi.anaconda.org/scientific-python-nightly-wheels/simple https://pypi.anaconda.org/liberfa/simple
 
 # Run the tests in a temporary directory to make sure that we don't import
 # package from the source tree
@@ -32,6 +32,7 @@ description =
 deps =
     # The devdeps factor is intended to be used to install the latest developer version
     # or nightly wheel of key dependencies.
+    devdeps: pyerfa>=0.0.dev0
     devdeps: numpy>=0.0.dev0
     devdeps: astropy>=0.0.dev0