diff --git a/requirements.txt b/requirements.txt
index 1143736..571d8a3 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,5 @@
 docopt; python_version >= '3.0'
+types-docopt; python_version >= '3.0'
 anytree; python_version >= '3.0'
 pyfzf; python_version >= '3.0'
 fusepy; python_version >= '3.0'
diff --git a/tests-requirements.txt b/tests-requirements.txt
index 8e826f4..fa48b04 100644
--- a/tests-requirements.txt
+++ b/tests-requirements.txt
@@ -4,3 +4,4 @@ nose2; python_version >= '3.0'
 coverage; python_version >= '3.0'
 coveralls; python_version >= '3.0'
 pylint; python_version > '3.0'
+mypy; python_version > '3.0'
diff --git a/tests.sh b/tests.sh
index ee403db..4e81638 100755
--- a/tests.sh
+++ b/tests.sh
@@ -22,6 +22,7 @@ pyflakes tests/
 # R0911: Too many return statements
 # R0903: Too few public methods
 # R0801: Similar lines in 2 files
+# R0902: Too many instance attributes
 pylint --version
 pylint \
   --disable=R0914 \
@@ -31,6 +32,7 @@ pylint \
   --disable=R0911 \
   --disable=R0903 \
   --disable=R0801 \
+  --disable=R0902 \
   catcli/
 pylint \
   --disable=W0212 \
@@ -39,6 +41,10 @@ pylint \
   --disable=R0801 \
   tests/
 
+mypy \
+  --strict \
+  catcli/
+
 nosebin="nose2"
 PYTHONPATH=catcli ${nosebin} --with-coverage --coverage=catcli