diff --git a/builtin/builtin.mbti b/builtin/builtin.mbti
index 8010054e4..6ead74d8b 100644
--- a/builtin/builtin.mbti
+++ b/builtin/builtin.mbti
@@ -718,7 +718,7 @@ impl FixedArray {
 }
 
 impl Bytes {
-  blit(Bytes, Int, Bytes, Int, Int) -> Unit
+  blit(Bytes, Int, Bytes, Int, Int) -> Unit //deprecated
   copy(Bytes) -> Bytes
   length(Bytes) -> Int
   make(Int, Byte) -> Bytes
diff --git a/builtin/bytes.mbt b/builtin/bytes.mbt
index fd7d45cd7..a8149574d 100644
--- a/builtin/bytes.mbt
+++ b/builtin/bytes.mbt
@@ -240,7 +240,7 @@ pub fn FixedArray::blit_from_bytes(
 /// }
 /// ```
 pub fn Bytes::copy(self : Bytes) -> Bytes {
-  Bytes::new(self.length())..blit(0, self, 0, self.length())
+  Bytes::makei(self.length(), fn(i) { self[i] })
 }
 
 ///|
diff --git a/builtin/bytes_block.mbt b/builtin/bytes_block.mbt
index 108c82480..c3293f55a 100644
--- a/builtin/bytes_block.mbt
+++ b/builtin/bytes_block.mbt
@@ -24,43 +24,7 @@ fn Bytes::unsafe_blit(
 ///|
 /// Copies a sequence of bytes from a source byte sequence to a destination byte
 /// sequence.
-///
-/// Parameters:
-///
-/// * `self` : The destination byte sequence where bytes will be copied to.
-/// * `dst_offset` : The starting position in the destination sequence where
-/// bytes will be written.
-/// * `src` : The source byte sequence from which bytes will be copied.
-/// * `src_offset` : The starting position in the source sequence from which
-/// bytes will be read.
-/// * `length` : The number of bytes to copy.
-///
-/// Throws a runtime error if:
-///
-/// * `length` is negative
-/// * `dst_offset` is negative
-/// * `src_offset` is negative
-/// * The range `[dst_offset, dst_offset + length)` exceeds the length of the
-/// destination sequence
-/// * The range `[src_offset, src_offset + length)` exceeds the length of the
-/// source sequence
-///
-/// Example:
-///
-/// ```moonbit
-/// test "Bytes::blit" {
-///   let dst = Bytes::of_string("Hello, world!")
-///   let src = Bytes::of_string("MOONBIT")
-///   dst.blit(14, src, 0, 8)
-///   @json.inspect!(dst.to_unchecked_string(), content="Hello, MOONd!")
-/// }
-///
-/// test "panic Bytes::blit/out_of_bounds" {
-///   let dst = Bytes::of_string("Hello")
-///   let src = Bytes::of_string("World")
-///   ignore(dst.blit(6, src, 0, 20)) // Range exceeds destination length
-/// }
-/// ```
+/// @alert deprecated "Bytes is about to be changed to immutable, use `FixedArray[Byte]` instead"
 pub fn Bytes::blit(
   self : Bytes,
   dst_offset : Int,
diff --git a/builtin/panic_test.mbt b/builtin/panic_test.mbt
index bd062add4..4d7dd05b0 100644
--- a/builtin/panic_test.mbt
+++ b/builtin/panic_test.mbt
@@ -197,27 +197,6 @@ test "panic from_octets coverage for empty octets" {
   BigInt::from_octets(b"") |> ignore
 }
 
-test "panic blit_negative_length" {
-  let b1 = Bytes::of_string("abcdef")
-  let b2 = Bytes::of_string("ABCDEF")
-  // Attempt to blit with a negative length
-  b1.blit(2, b2, 3, -1)
-}
-
-test "panic blit_out_of_bounds_src" {
-  let b1 = Bytes::of_string("abcdef")
-  let b2 = Bytes::of_string("ABCDEF")
-  // Attempt to blit with src_offset + length exceeding src length
-  b1.blit(4, b2, 10, 4)
-}
-
-test "panic blit_out_of_bounds_dst" {
-  let b1 = Bytes::of_string("abcdef")
-  let b2 = Bytes::of_string("ABCDEF")
-  // Attempt to blit with dst_offset + length exceeding dst length
-  b1.blit(8, b2, 6, 6)
-}
-
 test "panic sub_string with invalid byte_length" {
   let bytes = Bytes::of_string("Hello, World!")
   bytes.to_unchecked_string(offset=0, length=-1) |> ignore