diff --git a/ .readthedocs.yml b/ .readthedocs.yml
new file mode 100644
index 000000000..6c021be08
--- /dev/null
+++ b/ .readthedocs.yml	
@@ -0,0 +1,17 @@
+# .readthedocs.yml
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Optionally build your docs in additional formats such as PDF and ePub
+formats:
+  - htmlzip
+  - pdf
+
+# Optionally set the version of Python and requirements required to build your docs
+python:
+  version: 2.7
+  install:
+    - requirements: docs/requirements.txt
diff --git a/docs/requirements.txt b/docs/requirements.txt
index 6dca554cb..bb93e2125 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -2,7 +2,7 @@
 # pip install --user -r requirements.txt
 #
 sphinx>=1.8.4
-breathe>=4.11.1
+breathe==4.11.1
 sphinx-rtd-theme
 sphinxcontrib-blockdiag>=1.5.5
 sphinxcontrib-seqdiag>=0.8.5