diff --git a/test-support/reference-trie/src/substrate_like.rs b/test-support/reference-trie/src/substrate_like.rs
index e9b67489..53f78a5c 100644
--- a/test-support/reference-trie/src/substrate_like.rs
+++ b/test-support/reference-trie/src/substrate_like.rs
@@ -15,7 +15,7 @@
 //! Codec and layout configuration similar to upstream default substrate one.
 
 use super::{CodecError as Error, NodeCodec as NodeCodecT, *};
-use trie_db::node::Value;
+use trie_db::{nibble_ops, node::Value};
 
 /// No extension trie with no hashed value.
 pub struct HashedValueNoExt;
@@ -45,7 +45,6 @@ impl TrieLayout for HashedValueNoExtThreshold {
 /// Constants specific to encoding with external value node support.
 pub mod trie_constants {
 	const FIRST_PREFIX: u8 = 0b_00 << 6;
-	pub const NIBBLE_SIZE_BOUND: usize = u16::max_value() as usize;
 	pub const LEAF_PREFIX_MASK: u8 = 0b_01 << 6;
 	pub const BRANCH_WITHOUT_MASK: u8 = 0b_10 << 6;
 	pub const BRANCH_WITH_MASK: u8 = 0b_11 << 6;
@@ -263,8 +262,6 @@ fn partial_from_iterator_encode<I: Iterator<Item = u8>>(
 	nibble_count: usize,
 	node_kind: NodeKind,
 ) -> Vec<u8> {
-	let nibble_count = std::cmp::min(trie_constants::NIBBLE_SIZE_BOUND, nibble_count);
-
 	let mut output = Vec::with_capacity(4 + (nibble_count / nibble_ops::NIBBLE_PER_BYTE));
 	match node_kind {
 		NodeKind::Leaf => NodeHeader::Leaf(nibble_count).encode_to(&mut output),
@@ -378,8 +375,6 @@ pub(crate) fn size_and_prefix_iterator(
 	prefix: u8,
 	prefix_mask: usize,
 ) -> impl Iterator<Item = u8> {
-	let size = std::cmp::min(trie_constants::NIBBLE_SIZE_BOUND, size);
-
 	let max_value = 255u8 >> prefix_mask;
 	let l1 = std::cmp::min(max_value as usize - 1, size);
 	let (first_byte, mut rem) = if size == l1 {
@@ -422,14 +417,13 @@ fn decode_size(first: u8, input: &mut impl Input, prefix_mask: usize) -> Result<
 		return Ok(result)
 	}
 	result -= 1;
-	while result <= trie_constants::NIBBLE_SIZE_BOUND {
+	loop {
 		let n = input.read_byte()? as usize;
 		if n < 255 {
 			return Ok(result + n + 1)
 		}
 		result += 255;
 	}
-	Ok(trie_constants::NIBBLE_SIZE_BOUND)
 }
 
 /// Reference implementation of a `TrieStream` without extension.
@@ -441,7 +435,7 @@ pub struct ReferenceTrieStreamNoExt {
 
 /// Create a leaf/branch node, encoding a number of nibbles.
 fn fuse_nibbles_node<'a>(nibbles: &'a [u8], kind: NodeKind) -> impl Iterator<Item = u8> + 'a {
-	let size = std::cmp::min(trie_constants::NIBBLE_SIZE_BOUND, nibbles.len());
+	let size = nibbles.len();
 
 	let iter_start = match kind {
 		NodeKind::Leaf => size_and_prefix_iterator(size, trie_constants::LEAF_PREFIX_MASK, 2),