add example file

.gitignore

@@ -3,3 +3,5 @@
 node_modules/
 vendor
 .idea
+internal/example/built-example
+coverage.txt

internal/example/example.go

@@ -0,0 +1,13 @@
+// minimal example CLI used for binary size checking
+
+package main
+
+import (
+	"os"
+
+	"github.com/urfave/cli/v2"
+)
+
+func main() {
+	(&cli.App{}).Run(os.Args)
+}