diff --git a/.mapping.json b/.mapping.json
index 4073a76..a9d4289 100644
--- a/.mapping.json
+++ b/.mapping.json
@@ -458,6 +458,7 @@
   "src/utils/events/types.ts":"metrika/frontend/watch/src/utils/events/types.ts",
   "src/utils/flagsStorage/__test__/flagsStorage.spec.ts":"metrika/frontend/watch/src/utils/flagsStorage/__test__/flagsStorage.spec.ts",
   "src/utils/flagsStorage/flagsStorage.ts":"metrika/frontend/watch/src/utils/flagsStorage/flagsStorage.ts",
+  "src/utils/fletcher/index.ts":"metrika/frontend/watch/src/utils/fletcher/index.ts",
   "src/utils/fnv32a/__tests__/fnv32a.spec.ts":"metrika/frontend/watch/src/utils/fnv32a/__tests__/fnv32a.spec.ts",
   "src/utils/fnv32a/fnv32a.ts":"metrika/frontend/watch/src/utils/fnv32a/fnv32a.ts",
   "src/utils/fnv32a/index.ts":"metrika/frontend/watch/src/utils/fnv32a/index.ts",
@@ -541,6 +542,7 @@
   "src/utils/phones/phonesDom.ts":"metrika/frontend/watch/src/utils/phones/phonesDom.ts",
   "src/utils/phones/phonesHide.ts":"metrika/frontend/watch/src/utils/phones/phonesHide.ts",
   "src/utils/phones/phonesSubscribe.ts":"metrika/frontend/watch/src/utils/phones/phonesSubscribe.ts",
+  "src/utils/promise/index.ts":"metrika/frontend/watch/src/utils/promise/index.ts",
   "src/utils/querystring/__tests__/querystring.spec.ts":"metrika/frontend/watch/src/utils/querystring/__tests__/querystring.spec.ts",
   "src/utils/querystring/index.ts":"metrika/frontend/watch/src/utils/querystring/index.ts",
   "src/utils/querystring/querystring.ts":"metrika/frontend/watch/src/utils/querystring/querystring.ts",
diff --git a/src/utils/fletcher/index.ts b/src/utils/fletcher/index.ts
new file mode 100644
index 0000000..7b1b135
--- /dev/null
+++ b/src/utils/fletcher/index.ts
@@ -0,0 +1,35 @@
+/* eslint-disable no-bitwise */
+/**
+ * Вычисляет чексумму данных по алгоритму Флетчера.
+ */
+export function fletcher(data: number[] | string) {
+    let { length } = data;
+    let i = 0;
+    let sum1 = 0xff;
+    let sum2 = 0xff;
+    let tlen;
+    let ch;
+    let ch2;
+    while (length) {
+        tlen = length > 21 ? 21 : length;
+        length -= tlen;
+
+        do {
+            ch = typeof data === 'string' ? data.charCodeAt(i) : data[i];
+            i += 1;
+            if (ch > 255) {
+                ch2 = ch >> 8;
+                ch &= 0xff;
+                ch ^= ch2;
+            }
+            sum1 += ch;
+            sum2 += sum1;
+            // eslint-disable-next-line no-cond-assign
+        } while ((tlen -= 1));
+        sum1 = (sum1 & 0xff) + (sum1 >> 8);
+        sum2 = (sum2 & 0xff) + (sum2 >> 8);
+    }
+    const result =
+        (((sum1 & 0xff) + (sum1 >> 8)) << 8) | ((sum2 & 0xff) + (sum2 >> 8));
+    return result === 0xffff ? 0 : result;
+}
diff --git a/src/utils/index.ts b/src/utils/index.ts
index 22b4ba2..b0a9756 100644
--- a/src/utils/index.ts
+++ b/src/utils/index.ts
@@ -1,74 +1 @@
-/* eslint-disable no-bitwise */
-// https://github.com/RubenVerborgh/promiscuous !?!?
-import * as polyPromise from 'promise-polyfill';
-import { POLYFILLS_FEATURE } from 'generated/features';
-import { flags } from '@inject';
-import { toNativeOrFalse } from 'src/utils/function/isNativeFunction/toNativeOrFalse';
-import { includes } from 'src/utils/array/includes';
-import { bind } from './function/bind';
-import { getPath } from './object';
-
-/* eslint-disable-next-line import/no-mutable-exports */
-let PolyPromise: PromiseConstructor = window.Promise;
-
-if (flags[POLYFILLS_FEATURE]) {
-    const construct = toNativeOrFalse(PolyPromise as any, 'Promise');
-    const resolve = toNativeOrFalse(
-        getPath(PolyPromise, 'resolve')!,
-        'resolve',
-    );
-    const reject = toNativeOrFalse(getPath(PolyPromise, 'reject')!, 'reject');
-    const all = toNativeOrFalse(getPath(PolyPromise, 'all')!, 'all');
-    if (includes(false, [construct, resolve, reject, all])) {
-        PolyPromise = polyPromise.default;
-    } else {
-        const anyPromise = function promiseWrapper(a: any) {
-            return new Promise(a);
-        } as any;
-        anyPromise.resolve = bind(resolve as any, PolyPromise);
-        anyPromise.reject = bind(reject as any, PolyPromise);
-        anyPromise.all = bind(all as any, PolyPromise);
-        PolyPromise = anyPromise;
-    }
-}
-
-export { PolyPromise };
-
-/**
- * Вычисляет чексумму данных по алгоритму Флетчера.
- *
- * @param {Array|String} data
- *
- * @returns {Number}
- */
-export function fletcher(data: number[] | string) {
-    let { length } = data;
-    let i = 0;
-    let sum1 = 0xff;
-    let sum2 = 0xff;
-    let tlen;
-    let ch;
-    let ch2;
-    while (length) {
-        tlen = length > 21 ? 21 : length;
-        length -= tlen;
-
-        do {
-            ch = typeof data === 'string' ? data.charCodeAt(i) : data[i];
-            i += 1;
-            if (ch > 255) {
-                ch2 = ch >> 8;
-                ch &= 0xff;
-                ch ^= ch2;
-            }
-            sum1 += ch;
-            sum2 += sum1;
-            // eslint-disable-next-line no-cond-assign
-        } while ((tlen -= 1));
-        sum1 = (sum1 & 0xff) + (sum1 >> 8);
-        sum2 = (sum2 & 0xff) + (sum2 >> 8);
-    }
-    const result =
-        (((sum1 & 0xff) + (sum1 >> 8)) << 8) | ((sum2 & 0xff) + (sum2 >> 8));
-    return result === 0xffff ? 0 : result;
-}
+export * from './promise';
diff --git a/src/utils/promise/index.ts b/src/utils/promise/index.ts
new file mode 100644
index 0000000..25e7f78
--- /dev/null
+++ b/src/utils/promise/index.ts
@@ -0,0 +1,34 @@
+/* eslint-disable no-bitwise */
+// https://github.com/RubenVerborgh/promiscuous !?!?
+import * as polyPromise from 'promise-polyfill';
+import { POLYFILLS_FEATURE } from 'generated/features';
+import { flags } from '@inject';
+import { bind } from 'src/utils/function/bind';
+import { toNativeOrFalse } from 'src/utils/function/isNativeFunction/toNativeOrFalse';
+import { getPath } from 'src/utils/object';
+
+/* eslint-disable-next-line import/no-mutable-exports */
+export let PolyPromise: PromiseConstructor = window.Promise;
+
+if (flags[POLYFILLS_FEATURE]) {
+    const construct = toNativeOrFalse(PolyPromise as any, 'Promise');
+    const resolve = toNativeOrFalse(
+        getPath(PolyPromise, 'resolve')!,
+        'resolve',
+    );
+    const reject = toNativeOrFalse(getPath(PolyPromise, 'reject')!, 'reject');
+    const all = toNativeOrFalse(getPath(PolyPromise, 'all')!, 'all');
+    if (construct && resolve && reject && all) {
+        const anyPromise = function promiseWrapper(
+            a: ConstructorParameters<PromiseConstructor>[0],
+        ) {
+            return new Promise(a);
+        } as any;
+        anyPromise.resolve = bind(resolve, PolyPromise);
+        anyPromise.reject = bind(reject, PolyPromise);
+        anyPromise.all = bind(all, PolyPromise);
+        PolyPromise = anyPromise;
+    } else {
+        PolyPromise = polyPromise.default;
+    }
+}