diff --git a/dist/provider.d.ts b/dist/provider.d.ts
index 7a81faf..9610feb 100644
--- a/dist/provider.d.ts
+++ b/dist/provider.d.ts
@@ -1,6 +1,6 @@
 /// <reference types="node" />
 import { FirebaseApp } from "@firebase/app";
-import { Firestore } from "@firebase/firestore";
+import { Firestore, Bytes } from "@firebase/firestore";
 import * as Y from "yjs";
 import { ObservableV2 } from "lib0/observable";
 import * as awarenessProtocol from "y-protocols/awareness";
@@ -9,6 +9,7 @@ export interface Parameters {
     firebaseApp: FirebaseApp;
     ydoc: Y.Doc;
     path: string;
+    docMapper?: (bytes: Bytes) => object;
     maxUpdatesThreshold?: number;
     maxWaitTime?: number;
     maxWaitFirestoreTime?: number;
@@ -43,6 +44,7 @@ export declare class FireProvider extends ObservableV2<any> {
     peersReceivers: Set<string>;
     peersSenders: Set<string>;
     peersRTC: PeersRTC;
+    documentMapper: (bytes: Bytes) => object;
     cache: Uint8Array | null;
     maxCacheUpdates: number;
     cacheUpdateCount: number;
@@ -91,7 +93,7 @@ export declare class FireProvider extends ObservableV2<any> {
     consoleHandler: (message: any, data?: any) => void;
     destroy: () => void;
     kill: (keepReadOnly?: boolean) => void;
-    constructor({ firebaseApp, ydoc, path, maxUpdatesThreshold, maxWaitTime, maxWaitFirestoreTime, }: Parameters);
+    constructor({ firebaseApp, ydoc, path, docMapper, maxUpdatesThreshold, maxWaitTime, maxWaitFirestoreTime, }: Parameters);
 }
 export {};
 //# sourceMappingURL=provider.d.ts.map
\ No newline at end of file
diff --git a/dist/provider.d.ts.map b/dist/provider.d.ts.map
index f0fce07..aeeb00e 100644
--- a/dist/provider.d.ts.map
+++ b/dist/provider.d.ts.map
@@ -1 +1 @@
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\ No newline at end of file
+{"version":3,"file":"provider.d.ts","sourceRoot":"","sources":["../src/provider.ts"],"names":[],"mappings":";AAAA,OAAO,EAAE,WAAW,EAAE,MAAM,eAAe,CAAC;AAC5C,OAAO,EAEL,SAAS,EAKT,KAAK,EACN,MAAM,qBAAqB,CAAC;AAE7B,OAAO,KAAK,CAAC,MAAM,KAAK,CAAC;AACzB,OAAO,EAAE,YAAY,EAAE,MAAM,iBAAiB,CAAC;AAC/C,OAAO,KAAK,iBAAiB,MAAM,uBAAuB,CAAC;AAG3D,OAAO,EAAE,MAAM,EAAE,MAAM,UAAU,CAAC;AAGlC,MAAM,WAAW,UAAU;IACzB,WAAW,EAAE,WAAW,CAAC;IACzB,IAAI,EAAE,CAAC,CAAC,GAAG,CAAC;IACZ,IAAI,EAAE,MAAM,CAAC;IACb,SAAS,CAAC,EAAE,CAAC,KAAK,EAAE,KAAK,KAAK,MAAM,CAAC;IACrC,mBAAmB,CAAC,EAAE,MAAM,CAAC;IAC7B,WAAW,CAAC,EAAE,MAAM,CAAC;IACrB,oBAAoB,CAAC,EAAE,MAAM,CAAC;CAC/B;AAED,UAAU,QAAQ;IAChB,SAAS,EAAE;QACT,CAAC,GAAG,EAAE,MAAM,GAAG,MAAM,CAAC;KACvB,CAAC;IACF,OAAO,EAAE;QACP,CAAC,GAAG,EAAE,MAAM,GAAG,MAAM,CAAC;KACvB,CAAC;CACH;AAED;;;;;;;;;GASG;AACH,qBAAa,YAAa,SAAQ,YAAY,CAAC,GAAG,CAAC;IACjD,QAAQ,CAAC,GAAG,EAAE,CAAC,CAAC,GAAG,CAAC;IACpB,SAAS,EAAE,iBAAiB,CAAC,SAAS,CAAC;IACvC,QAAQ,CAAC,YAAY,EAAE,MAAM,CAAC;IAC9B,QAAQ,CAAC,WAAW,EAAE,WAAW,CAAC;IAClC,QAAQ,CAAC,EAAE,EAAE,SAAS,CAAC;IACvB,GAAG,EAAE,MAAM,CAAC;IACZ,UAAU,EAAE,MAAM,CAAK;IAEvB,OAAO,EAAE,MAAM,EAAE,CAAM;IACvB,cAAc,EAAE,GAAG,CAAC,MAAM,CAAC,CAAe;IAC1C,YAAY,EAAE,GAAG,CAAC,MAAM,CAAC,CAAe;IAExC,QAAQ,EAAE,QAAQ,CAGhB;IAEF,cAAc,EAAE,CAAC,KAAK,EAAE,KAAK,KAAK,MAAM,CAAmC;IAE3E,KAAK,EAAE,UAAU,GAAG,IAAI,CAAC;IACzB,eAAe,EAAE,MAAM,CAAM;IAC7B,gBAAgB,EAAE,MAAM,CAAK;IAC7B,YAAY,EAAE,MAAM,GAAG,MAAM,GAAG,MAAM,CAAC,OAAO,CAAC;IAC/C,UAAU,EAAE,MAAM,CAAO;IACzB,gBAAgB,EAAE,MAAM,GAAG,MAAM,GAAG,MAAM,CAAC,OAAO,CAAC;IACnD,gBAAgB,EAAE,MAAM,CAAQ;IAEhC,yBAAyB,EAAE,MAAM,CAAwB;IAEzD,kBAAkB,EAAE,YAAY,CAAC,GAAG,CAAC,CAAsB;IAC3D,eAAe,EAAE,MAAM,GAAG,MAAM,GAAG,MAAM,CAAC,OAAO,CAAC;IAElD,OAAO,CAAC,eAAe,CAAC,CAAc;IACtC,OAAO,CAAC,eAAe,CAAC,CAAc;IAEtC,IAAI,gBAAgB,WAEnB;IAED,KAAK,EAAE,OAAO,CAAS;IAChB,OAAO,EAAE,MAAM,IAAI,CAAC;IACpB,SAAS,EAAE,MAAM,IAAI,CAAC;IACtB,QAAQ,EAAE,CAAC,MAAM,EAAE,OAAO,KAAK,IAAI,CAAC;IAE3C,IAAI,sBAaF;IAEF,SAAS,sBAOP;IAEF,WAAW,sBAOT;IAEF,WAAW,sBAMT;IAEF,eAAe,aAQb;IAEF,SAAS,aA+BP;IAEF,SAAS,aAgCP;IAEF,SAAS,aAOP;IAEF,gBAAgB,sBAcd;IAEF,cAAc,aACF,MAAM,EAAE,YACR,IAAI,MAAM,CAAC,YACX,OAAO,cAuCjB;IAEF,eAAe;cAKP,OAAO;iBACJ,OAAO;cACV,UAAU,GAAG,IAAI;eAoBvB;IAEF,eAAe,sBAiBb;IAEF,oBAAoB,aAelB;IAEF,SAAS,SAAU,MAAM,UASvB;IAEF,WAAW;cAA8B,OAAO;gBAAU,UAAU;eA4BlE;IAEF,aAAa,WAAY,UAAU,UAAU,GAAG,UAyB9C;IAEF,sBAAsB;eAKR,MAAM,EAAE;iBAAW,MAAM,EAAE;iBAAW,MAAM,EAAE;eAClD,OAAO,UAWf;IAEF,cAAc,YAAa,GAAG,SAAQ,GAAG,UAQvC;IAIF,OAAO,aAKL;IAEF,IAAI,kBAAkB,OAAO,UA+B3B;gBAEU,EACV,WAAW,EACX,IAAI,EACJ,IAAI,EACJ,SAAS,EACT,mBAAmB,EACnB,WAAW,EACX,oBAAoB,GACrB,EAAE,UAAU;CAiBd"}
\ No newline at end of file
diff --git a/dist/provider.js b/dist/provider.js
index 94014e6..a90dc73 100644
--- a/dist/provider.js
+++ b/dist/provider.js
@@ -30,7 +30,7 @@ export class FireProvider extends ObservableV2 {
     get clientTimeOffset() {
         return this.timeOffset;
     }
-    constructor({ firebaseApp, ydoc, path, maxUpdatesThreshold, maxWaitTime, maxWaitFirestoreTime, }) {
+    constructor({ firebaseApp, ydoc, path, docMapper, maxUpdatesThreshold, maxWaitTime, maxWaitFirestoreTime, }) {
         super();
         this.timeOffset = 0; // offset to server time in mili seconds
         this.clients = [];
@@ -40,6 +40,7 @@ export class FireProvider extends ObservableV2 {
             receivers: {},
             senders: {},
         };
+        this.documentMapper = (bytes) => ({ content: bytes });
         this.maxCacheUpdates = 20;
         this.cacheUpdateCount = 0;
         this.maxRTCWait = 100;
@@ -237,7 +238,7 @@ export class FireProvider extends ObservableV2 {
             try {
                 // current document to firestore
                 const ref = doc(this.db, this.documentPath);
-                yield setDoc(ref, { content: Bytes.fromUint8Array(Y.encodeStateAsUpdate(this.doc)) }, { merge: true });
+                yield setDoc(ref, this.documentMapper(Bytes.fromUint8Array(Y.encodeStateAsUpdate(this.doc))), { merge: true });
                 this.deleteLocal(); // We have successfully saved to Firestore, empty indexedDb for now
             }
             catch (error) {
@@ -382,6 +383,8 @@ export class FireProvider extends ObservableV2 {
         this.db = getFirestore(this.firebaseApp);
         this.doc = ydoc;
         this.documentPath = path;
+        if (docMapper)
+            this.documentMapper = docMapper;
         if (maxUpdatesThreshold)
             this.maxCacheUpdates = maxUpdatesThreshold;
         if (maxWaitTime)
diff --git a/package.json b/package.json
index ee58e85..3e5bc24 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "y-fire",
-  "version": "2.1.0",
+  "version": "2.1.1",
   "description": "A firebase (firestore) provider for Yjs",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",