diff --git a/array/array.mbt b/array/array.mbt
index 958d255a6..a5e4674c1 100644
--- a/array/array.mbt
+++ b/array/array.mbt
@@ -54,41 +54,6 @@ pub fn push_iter[T](self : Array[T], iter : Iter[T]) -> Unit {
   }
 }
 
-///|
-/// Creates a new array of the specified length, where each element is
-/// initialized using an index-based initialization function.
-///
-/// Parameters:
-///
-/// * `length` : The length of the new array. If `length` is less than or equal
-/// to 0, returns an empty array.
-/// * `initializer` : A function that takes an index (starting from 0) and
-/// returns a value of type `T`. This function is called for each index to
-/// initialize the corresponding element.
-///
-/// Returns a new array of type `Array[T]` with the specified length, where each
-/// element is initialized using the provided function.
-///
-/// Example:
-///
-/// ```moonbit
-/// test "Array::makei" {
-///   let arr = Array::makei(3, fn(i) { i * 2 })
-///   inspect!(arr, content="[0, 2, 4]")
-/// }
-/// ```
-pub fn Array::makei[T](length : Int, value : (Int) -> T) -> Array[T] {
-  if length <= 0 {
-    []
-  } else {
-    let array = Array::make(length, value(0))
-    for i in 1..<length {
-      array[i] = value(i)
-    }
-    array
-  }
-}
-
 ///|
 /// Shuffle the array using Knuth shuffle
 /// 
diff --git a/array/array.mbti b/array/array.mbti
index e86405602..4dfcd9a5f 100644
--- a/array/array.mbti
+++ b/array/array.mbti
@@ -54,7 +54,6 @@ impl Array {
   from_iter[T](Iter[T]) -> Self[T]
   join(Self[String], String) -> String
   last[A](Self[A]) -> A?
-  makei[T](Int, (Int) -> T) -> Self[T]
   map_option[A, B](Self[A], (A) -> B?) -> Self[B] //deprecated
   push_iter[T](Self[T], Iter[T]) -> Unit
   shuffle[T](Self[T], rand~ : (Int) -> Int) -> Self[T]
diff --git a/array/array_test.mbt b/array/array_test.mbt
index bfca078e5..f4cb55544 100644
--- a/array/array_test.mbt
+++ b/array/array_test.mbt
@@ -567,7 +567,7 @@ test "Array::makei with zero length" {
 }
 
 ///|
-test "Array::makei with negative length" {
+test "panic/Array::makei with negative length" {
   let arr = Array::makei(-1, fn(i) { i * 2 })
   assert_eq!(arr, [])
 }
diff --git a/builtin/array.mbt b/builtin/array.mbt
index 26a4543c5..1ece94f61 100644
--- a/builtin/array.mbt
+++ b/builtin/array.mbt
@@ -74,6 +74,37 @@ pub fn Array::make[T](len : Int, elem : T) -> Array[T] {
   arr
 }
 
+///|
+/// Creates a new array of the specified length, where each element is
+/// initialized using an index-based initialization function.
+///
+/// Parameters:
+///
+/// * `length` : The length of the new array. If `length` is less than or equal
+/// to 0, returns an empty array.
+/// * `initializer` : A function that takes an index (starting from 0) and
+/// returns a value of type `T`. This function is called for each index to
+/// initialize the corresponding element.
+///
+/// Returns a new array of type `Array[T]` with the specified length, where each
+/// element is initialized using the provided function.
+///
+/// Example:
+///
+/// ```moonbit
+/// test "Array::makei" {
+///   let arr = Array::makei(3, fn(i) { i * 2 })
+///   inspect!(arr, content="[0, 2, 4]")
+/// }
+/// ```
+pub fn Array::makei[T](len : Int, value : (Int) -> T) -> Array[T] {
+  let arr = Array::make_uninit(len)
+  for i in 0..<len {
+    arr.unsafe_set(i, value(i))
+  }
+  arr
+}
+
 ///|
 /// Returns the total capacity of the array, which is the number of elements that
 /// the array can hold without requiring reallocation of its internal buffer.
diff --git a/builtin/builtin.mbti b/builtin/builtin.mbti
index a4851de06..4d782531d 100644
--- a/builtin/builtin.mbti
+++ b/builtin/builtin.mbti
@@ -81,6 +81,7 @@ impl Array {
   iter2[A](Self[A]) -> Iter2[Int, A]
   length[T](Self[T]) -> Int
   make[T](Int, T) -> Self[T]
+  makei[T](Int, (Int) -> T) -> Self[T]
   map[T, U](Self[T], (T) -> U) -> Self[U]
   map_inplace[T](Self[T], (T) -> T) -> Unit
   mapi[T, U](Self[T], (Int, T) -> U) -> Self[U]