diff --git a/test/surgeon/subroutines/readSubroutine.js b/test/surgeon/subroutines/readSubroutine.js
index 19aaba2..9c051f9 100644
--- a/test/surgeon/subroutines/readSubroutine.js
+++ b/test/surgeon/subroutines/readSubroutine.js
@@ -1,3 +1,5 @@
+// @flow
+
 import test from 'ava';
 import sinon from 'sinon';
 import readSubroutine from '../../../src/subroutines/readSubroutine';
diff --git a/test/surgeon/subroutines/selectSubroutine.js b/test/surgeon/subroutines/selectSubroutine.js
index 7a3cd41..c081ae5 100644
--- a/test/surgeon/subroutines/selectSubroutine.js
+++ b/test/surgeon/subroutines/selectSubroutine.js
@@ -1,3 +1,5 @@
+// @flow
+
 import test from 'ava';
 import sinon from 'sinon';
 import selectSubroutine from '../../../src/subroutines/selectSubroutine';