diff --git a/src/OneScript.Native/Runtime/BuiltInFunctions.cs b/src/OneScript.Native/Runtime/BuiltInFunctions.cs
index 1bb5c2e3f..861209f24 100644
--- a/src/OneScript.Native/Runtime/BuiltInFunctions.cs
+++ b/src/OneScript.Native/Runtime/BuiltInFunctions.cs
@@ -265,6 +265,12 @@ public static int StrEntryCount(string where, string what)
         [ContextMethod("НачалоМесяца", "BegOfMonth")]
         public static DateTime BegOfMonth(DateTime date) => new DateTime(date.Year, date.Month, 1);
 
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        [ContextMethod("НачалоНедели", "BegOfWeek")]
+        public static DateTime BegOfWeek(DateTime date)
+            => new DateTime(date.Year, date.Month, date.Day)
+                .AddDays(-((int)date.DayOfWeek+6)%7);
+
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         [ContextMethod("НачалоДня", "BegOfDay")]
         public static DateTime BegOfDay(DateTime date) => new DateTime(date.Year, date.Month, date.Day);
@@ -321,6 +327,12 @@ public static DateTime EndOfMonth(DateTime date)
             return new DateTime(year, month, DateTime.DaysInMonth(year, month), 23, 59, 59);
         }
 
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        [ContextMethod("КонецНедели", "EndOfWeek")]
+        public static DateTime EndOfWeek(DateTime date)
+            => new DateTime(date.Year, date.Month, date.Day, 23, 59, 59)
+                .AddDays((7-(int)date.DayOfWeek) % 7);
+
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         [ContextMethod("КонецДня", "EndOfDay")]
         public static DateTime EndOfDay(DateTime date) => new DateTime(date.Year, date.Month, date.Day, 23, 59, 59);