diff --git a/.travis.yml b/.travis.yml
index ca6a426ea..d8094ef4d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,7 +14,8 @@ addons:
     - clang-9
     - build-essential pkg-config
     - cmake
-    - libpython-dev python-numpy
+    - python3-dev libpython-dev
+    - python3-numpy
     - libboost-all-dev
 
 # before_install:
diff --git a/cython/requirements.txt b/cython/requirements.txt
index cd77b097d..8d3c7aeb4 100644
--- a/cython/requirements.txt
+++ b/cython/requirements.txt
@@ -1,3 +1,3 @@
 Cython>=0.25.2
 backports_abc>=0.5
-numpy>=1.12.0
+numpy>=1.11.0