diff --git a/base-64/base-64-tests.ts b/base-64/base-64-tests.ts
new file mode 100644
index 0000000000..0f33ff9700
--- /dev/null
+++ b/base-64/base-64-tests.ts
@@ -0,0 +1,11 @@
+import * as base64 from 'base-64';
+import * as utf8 from 'utf8';
+ 
+let text = 'foo © bar 𝌆 baz';
+let bytes = utf8.encode(text);
+let encoded = base64.encode(bytes);
+// → 'Zm9vIMKpIGJhciDwnYyGIGJheg==' 
+
+encoded = 'Zm9vIMKpIGJhciDwnYyGIGJheg==';
+bytes = base64.decode(encoded);
+text = utf8.decode(bytes);
diff --git a/base-64/tsconfig.json b/base-64/tsconfig.json
index 0f2be78cfb..e12b07da98 100644
--- a/base-64/tsconfig.json
+++ b/base-64/tsconfig.json
@@ -13,6 +13,7 @@
         "forceConsistentCasingInFileNames": true
     },
     "files": [
-        "index.d.ts"
+        "index.d.ts",
+        "base-64-tests.ts"
     ]
 }
\ No newline at end of file