diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..de0ac24
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "ex01/ex01/bats"]
+	path = ex01/ex01/bats
+	url = https://github.com/sstephenson/bats.git
diff --git a/ex01/bats b/ex01/bats
new file mode 160000
index 0000000..0360811
--- /dev/null
+++ b/ex01/bats
@@ -0,0 +1 @@
+Subproject commit 03608115df2071fff4eaaff1605768c275e5f81f
diff --git a/ex01/ex01/bats b/ex01/ex01/bats
new file mode 160000
index 0000000..0360811
--- /dev/null
+++ b/ex01/ex01/bats
@@ -0,0 +1 @@
+Subproject commit 03608115df2071fff4eaaff1605768c275e5f81f
diff --git a/ex01/hello_world.sh b/ex01/hello_world.sh
new file mode 100755
index 0000000..7a79f61
--- /dev/null
+++ b/ex01/hello_world.sh
@@ -0,0 +1,6 @@
+#!/bin/bash
+if [[ $1 = "" ]] ; then
+    echo "Hello, World!"
+else
+    echo "Hello, ${1}!"
+fi