diff --git a/packages/signing/signDocument.ts b/packages/signing/signDocument.ts
index fba752b0a..69280acb8 100644
--- a/packages/signing/signDocument.ts
+++ b/packages/signing/signDocument.ts
@@ -1,4 +1,26 @@
-export const signDocument = (documentAsBase64: string): string => {
-    
-  return documentAsBase64;
+const signer = require("../../node_modules/node-signpdf/dist/signpdf");
+const {
+  pdfkitAddPlaceholder,
+} = require("../../node_modules/node-signpdf/dist/helpers/pdfkitAddPlaceholder");
+import * as fs from "fs";
+
+export const signDocument = (documentAsBase64: string): any => {
+  const pdfBuffer = Buffer.from(documentAsBase64, "base64");
+  const certBuffer = fs.readFileSync("public/certificate.p12");
+
+  console.log("adding placeholder..");
+  console.log(signer.pdfkitAddPlaceholder);
+  const inputBuffer = signer.pdfkitAddPlaceholder({
+    pdfBuffer,
+    reason: "Signed Certificate.",
+    contactInfo: "sign@example.com",
+    name: "Example",
+    location: "Jakarta",
+    signatureLength: certBuffer.length,
+  });
+
+  console.log("signing..");
+  const signedPdf = new signer.SignPdf().sign(inputBuffer, certBuffer);
+
+  return signedPdf;
 };