diff --git a/src/keri/app/credentialing.ts b/src/keri/app/credentialing.ts
index 44d14131..ee74415b 100644
--- a/src/keri/app/credentialing.ts
+++ b/src/keri/app/credentialing.ts
@@ -17,8 +17,6 @@ import { Serder } from '../core/serder';
 import { Siger } from '../core/siger';
 import { TextDecoder } from 'util';
 import { TraitDex } from './habery';
-import { Prefixer } from '../core/prefixer';
-import { Seqner } from '../core/seqner';
 import {
     serializeACDCAttachment,
     serializeIssExnAttachment,
@@ -776,9 +774,7 @@ export class Ipex {
             i: recp,
         };
 
-        let prefixer = new Prefixer({ raw: b(acdc.raw) });
-        let seqner = new Seqner({ sn: acdc.sn });
-        let acdcAtc = d(serializeACDCAttachment(prefixer, seqner, acdcSaider));
+        let acdcAtc = d(serializeACDCAttachment(acdc, acdcSaider));
         let issAtc = d(serializeIssExnAttachment(anc, issSaider));
 
         let embeds: any = {
diff --git a/src/keri/core/utils.ts b/src/keri/core/utils.ts
index 76952896..07d5d3d0 100644
--- a/src/keri/core/utils.ts
+++ b/src/keri/core/utils.ts
@@ -3,6 +3,7 @@ import { Seqner } from './seqner';
 import { Prefixer } from './prefixer';
 import { Saider } from './saider';
 import { Serder } from './serder';
+import { b } from './core';
 
 export function pad(n: any, width = 3, z = 0) {
     return (String(z).repeat(width) + String(n)).slice(String(n).length);
@@ -116,33 +117,12 @@ export function bytesToInt(ar: Uint8Array): number {
     return value;
 }
 
-export function serialize(
-    creder: any,
-    prefixer: any,
-    seqner: any,
-    saider: any
-) {
-    let craw = creder.raw;
-    let ctr = new Counter({ code: CtrDex.SealSourceTriples, count: 1 }).qb64b;
-    let prefix = prefixer.qb64b;
-    let seq = seqner.qb64b;
-    let said = saider.qb64b;
-    let newCraw = new Uint8Array(
-        craw.length + ctr.length + prefix.length + seq.length + said.length
-    );
-    newCraw.set(craw);
-    newCraw.set(ctr, craw.length);
-    newCraw.set(prefix, craw.length + ctr.length);
-    newCraw.set(seq, craw.length + ctr.length + prefix.length);
-    newCraw.set(said, craw.length + ctr.length + prefix.length + seq.length);
-    return newCraw;
-}
-
 export function serializeACDCAttachment(
-    prefixer: Prefixer,
-    seqner: Seqner,
+    acdc: Serder,
     saider: Saider
 ): Uint8Array {
+    let prefixer = new Prefixer({ raw: b(acdc.raw) });
+    let seqner = new Seqner({ sn: acdc.sn });
     let craw = new Uint8Array();
     let ctr = new Counter({ code: CtrDex.SealSourceTriples, count: 1 }).qb64b;
     let prefix = prefixer.qb64b;
diff --git a/test/core/utils.test.ts b/test/core/utils.test.ts
new file mode 100644
index 00000000..40b294c2
--- /dev/null
+++ b/test/core/utils.test.ts
@@ -0,0 +1,38 @@
+import { Ident, Saider, Serder, Serials, d, versify } from '../../src';
+import {
+    serializeACDCAttachment,
+    serializeIssExnAttachment,
+} from '../../src/keri/core/utils';
+
+describe(serializeIssExnAttachment, () => {
+    it('serializes iss data', () => {
+        const [saider, data] = Saider.saidify({
+            d: '',
+            v: versify(Ident.KERI, undefined, Serials.JSON, 0),
+        });
+
+        const result = serializeIssExnAttachment(new Serder(data), saider);
+
+        expect(d(result)).toEqual(
+            '-VAS-GAB0AAAAAAAAAAAAAAAAAAAAAAAEKZPmzJqhx76bcC2ftPQgeRirmOd8ZBOtGVqHJrSm7F1'
+        );
+    });
+});
+
+describe(serializeACDCAttachment, () => {
+    it('serializes acdc data', () => {
+        const [saider, data] = Saider.saidify({
+            d: '',
+            v: versify(Ident.ACDC, undefined, Serials.JSON, 0),
+            a: {
+                LEI: '123',
+            },
+        });
+
+        const result = serializeACDCAttachment(new Serder(data), saider);
+
+        expect(d(result)).toEqual(
+            '-IABBHsiZCI6IkVORTZzbWw4X1NMZVIzdk9NajRJRExLX2Nn0AAAAAAAAAAAAAAAAAAAAAAAENE6sml8_SLeR3vOMj4IDLK_cgd-A-vtg0Jnu7ozdBjW'
+        );
+    });
+});