diff --git a/src/workflows/common.js b/src/workflows/common.js
new file mode 100644
index 0000000..6d6ed03
--- /dev/null
+++ b/src/workflows/common.js
@@ -0,0 +1,16 @@
+// Source: https://stackoverflow.com/a/66046176
+export const arrayBufferToBase64 = async (data) => {
+  // Use a FileReader to generate a base64 data URI
+  const base64url = await new Promise((r) => {
+    const reader = new FileReader();
+    reader.onload = () => r(reader.result);
+    reader.readAsDataURL(new Blob([data]));
+  });
+
+  /*
+  The result looks like
+  "data:application/octet-stream;base64,<your base64 data>",
+  so we split off the beginning:
+  */
+  return base64url.split(',', 2)[1]
+}