diff --git a/single_file_tests/hmac.go b/single_file_tests/hmac.go
new file mode 100644
index 0000000..fac7d13
--- /dev/null
+++ b/single_file_tests/hmac.go
@@ -0,0 +1,19 @@
+package main
+
+import (
+	"crypto/hmac"
+	"crypto/sha1"
+	"encoding/base64"
+	"fmt"
+)
+
+func main() {
+	key := []byte("aaaaaa")
+	mac := hmac.New(sha1.New, key)
+	mac.Write([]byte("Hello World!"))
+	hmacSum := mac.Sum(nil)
+
+	fmt.Printf("%x\n", hmacSum)
+	fmt.Printf("%s\n", base64.StdEncoding.EncodeToString(hmacSum))
+}
+