diff --git a/.circleci/config.yml b/.circleci/config.yml
index 0eef15f..f909f78 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -5,4 +5,5 @@ jobs:
       - image: purplekarrot/gcc-8
     steps:
       - checkout
-      - run: cd build && cmake -DCMAKE_BUILD_TYPE=Debug .. && make -j
+      - run: sudo apt-get update && sudo apt-get install doxygen doxygen-docs doxygen-latex doxygen-gui graphviz
+      - run: cd build && cmake -DCMAKE_BUILD_TYPE=Release .. && make -j
diff --git a/.travis.yml b/.travis.yml
index c4b8024..8cff79a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,6 +11,11 @@ addons:
         packages:
             - g++-7
             - clang-5.0
+            - doxygen
+            - doxygen-doc
+            - doxygen-latex
+            - doxygen-gui
+            - graphviz
 
 matrix:
   include:
@@ -45,7 +50,8 @@ matrix:
         BUILD_TYPE=Release
         BIN_DIR=bin
       before_install:
-        brew update
+        - brew update
+        - brew install doxygen graphviz
       install:
         brew upgrade cmake
     - os: osx