diff --git a/docs/index.rst b/docs/index.rst
index f0145139731eacb0370f8698e716628d818c009a..3211a31437cf4f892708f4f8ab4aad5a0d1e2ede 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -83,10 +83,11 @@ Otherwise :code:`PyInit` won't be generated by Cython
 and such module will be unimportable in Python. Normal import won't suffice.
 
 Please install Snakehouse in a separate venv. This is because it requires an ancient version of
-the templating library Mako_, because newer versions requires Python 3.8, and I wanted
+the templating library Mako_ and MarkupSafe_, because newer versions requires Python 3.8, and I wanted
 Snakehouse to support older Pythons as well.
 
 .. _Mako: https://pypi.org/project/Mako/1.1.0/
+.. _MarkupSafe: https://pypi.org/project/MarkupSafe/1.1.1/
 
 Contributions
 =============
diff --git a/requirements.txt b/requirements.txt
index 6a00477c18114da76428090b7fcd4c59eee17833..f920453702a376dfdcacaffe61b95fdbadf6c994 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,4 @@
 Cython
 mako==1.1.0
 satella
+MarkupSafe==1.1.1
\ No newline at end of file
diff --git a/setup.cfg b/setup.cfg
index 6cd163450899c074b96c593350daf7f37ef0c266..972017f716e84062fb359efa111536b8710b6078 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -35,6 +35,7 @@ install_requires =
     Cython
     mako == 1.1.0
     satella
+    MarkupSafe == 1.1.1
 
 python_requires = !=2.7.*,!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*
 packages = find: