diff --git a/packages/core/__tests__/convert.test.js b/packages/core/__tests__/convert.test.js
deleted file mode 100644
index 4f9c2a5f5..000000000
--- a/packages/core/__tests__/convert.test.js
+++ /dev/null
@@ -1,56 +0,0 @@
-import Convert from "../utils/convert";
-
-test("object to string", () => {
-  let objStr = Convert.toString({ hello: "world" });
-  expect(objStr).toStrictEqual(`{"hello":"world"}`);
-});
-
-test("array to string", () => {
-  let arrStr = Convert.toString(["hello", "world", "what"]);
-  expect(arrStr).toStrictEqual(`["hello","world","what"]`);
-});
-
-test("number to string", () => {
-  let numStr = Convert.toString(2010);
-  expect(numStr).toBe("2010");
-});
-
-test("bool to string", () => {
-  let boolStr = Convert.toString(true);
-  expect(boolStr).toBe("true");
-});
-
-test("null conversion", () => {
-  expect(Convert.toString(undefined)).toBeUndefined();
-});
-
-//fromString
-test("string to bool", () => {
-  expect(Convert.fromString("true")).toBe(true);
-  expect(Convert.fromString("false")).toBe(false);
-});
-
-test("string to int", () => {
-  expect(Convert.fromString("2010")).toBe(2010);
-});
-
-test("string to float", () => {
-  expect(Convert.fromString("20.2")).toBe(20.2);
-});
-
-test("string to object", () => {
-  let objStr = JSON.stringify({ hello: "world" });
-  expect(Convert.fromString(objStr)).toStrictEqual({ hello: "world" });
-});
-
-test("string to array", () => {
-  expect(Convert.fromString('["hello","world","what"]')).toStrictEqual([
-    "hello",
-    "world",
-    "what"
-  ]);
-});
-
-test("string to string", () => {
-  expect(Convert.fromString("hello")).toBe("hello");
-});
diff --git a/packages/core/models/note.js b/packages/core/models/note.js
index 6e2df2fd4..a40066c25 100644
--- a/packages/core/models/note.js
+++ b/packages/core/models/note.js
@@ -44,7 +44,8 @@ export default class Note {
   }
 
   delta() {
-    return this.notes.deltaStorage.read(this.note.id + "_delta");
+    if (this.note.locked) return [];
+    return this.notes.deltaStorage.read(this.note.content.delta);
   }
 
   color(color) {
@@ -84,21 +85,32 @@ export default class Note {
       password,
       JSON.stringify(this.note.content)
     );
+    let delta = await this.notes.collection.indexer.encrypt(
+      password,
+      JSON.stringify(await this.delta())
+    );
+    await this.notes.deltaStorage.write(this.note.content.delta, delta);
     this.note.locked = true;
     return await this.notes.collection.addItem(this.note);
   }
 
   async unlock(password, perm = false) {
-    let decrypted = await this.notes.collection.indexer.decrypt(
-      password,
-      this.note.content
+    let decrypted = JSON.parse(
+      await this.notes.collection.indexer.decrypt(password, this.note.content)
+    );
+    let delta = JSON.parse(
+      await this.notes.collection.indexer.decrypt(password, await this.delta())
     );
     if (perm) {
       this.note.locked = false;
-      this.note.content = JSON.parse(decrypted);
+      this.note.content = decrypted;
       await this.notes.collection.addItem(this.note);
+      await this.notes.deltaStorage.write(this.note.content.delta, delta);
     }
-    return { ...this.note, content: JSON.parse(decrypted) };
+    return {
+      ...this.note,
+      content: { ...decrypted, delta: delta }
+    };
   }
 }
 
diff --git a/packages/core/package.json b/packages/core/package.json
index 5d96fdc5e..d904d5814 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -20,6 +20,7 @@
     "fuzzysearch": "^1.0.3",
     "node-fetch": "^2.6.0",
     "qclone": "^1.0.4",
+    "teleport-javascript": "^1.0.0",
     "transfun": "^1.0.2"
   }
 }
diff --git a/packages/core/utils/convert.js b/packages/core/utils/convert.js
deleted file mode 100644
index 74aa8b022..000000000
--- a/packages/core/utils/convert.js
+++ /dev/null
@@ -1,21 +0,0 @@
-export default class Convert {
-  static toString(input) {
-    if (!input) return;
-    let type = typeof input;
-    if (type === "object") return JSON.stringify(input);
-    return input.toString();
-  }
-  static fromString(input) {
-    if (!input) return;
-    let firstChar = input[0];
-    if (firstChar == "[" || firstChar == "{") return JSON.parse(input);
-    if (!isNaN(parseFloat(input)) && input.includes("."))
-      return parseFloat(input);
-    if (!isNaN(parseInt(input))) return parseInt(input);
-    if (parseBoolean(input) !== undefined) return parseBoolean(input);
-    return input;
-  }
-}
-function parseBoolean(value) {
-  return value === "true" ? true : value === "false" ? false : undefined;
-}
diff --git a/packages/core/yarn.lock b/packages/core/yarn.lock
index dd3e5b3bb..602404bb0 100644
--- a/packages/core/yarn.lock
+++ b/packages/core/yarn.lock
@@ -4437,6 +4437,11 @@ tar@^4:
     safe-buffer "^5.1.2"
     yallist "^3.0.3"
 
+teleport-javascript@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/teleport-javascript/-/teleport-javascript-1.0.0.tgz#c9397fad598d662027e4d3a5fa7e7da1c8361547"
+  integrity sha512-j1llvWVFyEn/6XIFDfX5LAU43DXe0GCt3NfXDwJ8XpRRMkS+i50SAkonAONBy+vxwPFBd50MFU8a2uj8R/ccLg==
+
 test-exclude@^5.2.3:
   version "5.2.3"
   resolved "https://registry.yarnpkg.com/test-exclude/-/test-exclude-5.2.3.tgz#c3d3e1e311eb7ee405e092dac10aefd09091eac0"