diff --git a/doc-requirements.txt b/doc-requirements.txt
index d03b717..7572396 100644
--- a/doc-requirements.txt
+++ b/doc-requirements.txt
@@ -1,4 +1,4 @@
 sphinx>=1.3
 sphinxcontrib-napoleon>=0.4.3
 mock==4.0.3
-sphinx_rtd_theme
+sphinx_rtd_theme==0.5.2
diff --git a/test-requirements.txt b/test-requirements.txt
index 4982aa6..7d10b5f 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,3 +1,3 @@
 pytest==6.2.4
-pytest-cov
+pytest-cov==2.12.1
 pytest-catchlog==1.2.2