diff --git a/.tool-versions b/.tool-versions
index 43c2e079..f0ce08ce 100644
--- a/.tool-versions
+++ b/.tool-versions
@@ -1,3 +1,4 @@
+golang 1.21.5
 bats 1.8.2
 shellcheck 0.9.0
 shfmt 3.6.0
diff --git a/go.mod b/go.mod
new file mode 100644
index 00000000..4fae493e
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module asdf
+
+go 1.21.5