diff --git a/Cargo.toml b/Cargo.toml
index af8dbe5..23cba05 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,15 +12,15 @@ default = ["std"]
 std = []
 
 [dependencies]
-cfg-if = "0.1"
+cfg-if = "1.0"
 
 [dev-dependencies]
-faster-hex = "0.3"
+faster-hex = "0.6.1"
 criterion = "0.3"
-rand = "0.6"
-proptest = "0.9.4"
+rand = "0.8.5"
+proptest = "1.0.0"
 lazy_static = "1.3.0"
-bytes = "0.4"
+bytes = "1.2.0"
 blake2b-rs = "0.1.4"
 
 [[bench]]
diff --git a/benches/helper_benchmark.rs b/benches/helper_benchmark.rs
index b45b1c6..35353a4 100644
--- a/benches/helper_benchmark.rs
+++ b/benches/helper_benchmark.rs
@@ -10,7 +10,7 @@ fn bench(c: &mut Criterion) {
     c.bench_function("left_index_to_pos", |b| {
         let mut rng = thread_rng();
         b.iter(|| {
-            let leaf_index = rng.gen_range(50_000_000_000, 70_000_000_000);
+            let leaf_index = rng.gen_range(50_000_000_000..70_000_000_000);
             leaf_index_to_pos(leaf_index);
         });
     });
@@ -18,7 +18,7 @@ fn bench(c: &mut Criterion) {
     c.bench_function("left_index_to_mmr_size", |b| {
         let mut rng = thread_rng();
         b.iter(|| {
-            let leaf_index = rng.gen_range(50_000_000_000, 70_000_000_000);
+            let leaf_index = rng.gen_range(50_000_000_000..70_000_000_000);
             leaf_index_to_mmr_size(leaf_index);
         });
     });
diff --git a/src/tests/test_accumulate_headers.rs b/src/tests/test_accumulate_headers.rs
index 946ea54..1366970 100644
--- a/src/tests/test_accumulate_headers.rs
+++ b/src/tests/test_accumulate_headers.rs
@@ -1,7 +1,7 @@
 use super::new_blake2b;
 use crate::{leaf_index_to_pos, util::MemStore, MMRStore, Merge, MerkleProof, Result, MMR};
-use bytes::Bytes;
-use std::fmt::{self, Debug};
+use bytes::{Bytes, BytesMut};
+use std::fmt;
 
 #[derive(Clone)]
 struct Header {
@@ -42,9 +42,9 @@ struct HashWithTD {
 
 impl HashWithTD {
     fn serialize(&self) -> Bytes {
-        let mut data = self.hash.clone();
+        let mut data = BytesMut::from(self.hash.as_ref());
         data.extend(&self.td.to_le_bytes());
-        data
+        data.into()
     }
 
     fn deserialize(mut data: Bytes) -> Self {
@@ -57,12 +57,12 @@ impl HashWithTD {
     }
 }
 
-impl Debug for HashWithTD {
+impl fmt::Debug for HashWithTD {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         write!(
             f,
             "HashWithTD {{ hash: {}, td: {} }}",
-            faster_hex::hex_string(&self.hash).unwrap(),
+            faster_hex::hex_string(&self.hash),
             self.td
         )
     }
diff --git a/src/tests/test_mmr.rs b/src/tests/test_mmr.rs
index 2763fd3..10ad71b 100644
--- a/src/tests/test_mmr.rs
+++ b/src/tests/test_mmr.rs
@@ -64,7 +64,7 @@ fn test_mmr_root() {
         mmr.push(NumberHash::from(i)).unwrap();
     });
     let root = mmr.get_root().expect("get root");
-    let hex_root = hex_string(&root.0).unwrap();
+    let hex_root = hex_string(&root.0);
     assert_eq!(
         "f6794677f37a57df6a5ec36ce61036e43a36c1a009d05c81c9aa685dde1fd6e3",
         hex_root
@@ -154,7 +154,7 @@ proptest! {
         let mut leaves: Vec<u32> = (0..count).collect();
         let mut rng = thread_rng();
         leaves.shuffle(&mut rng);
-        let leaves_count = rng.gen_range(1, count - 1);
+        let leaves_count = rng.gen_range(1..count - 1);
         leaves.truncate(leaves_count as usize);
         test_mmr(count, leaves);
     }
diff --git a/src/tests/test_sequence.rs b/src/tests/test_sequence.rs
index 3844b0c..1d953a2 100644
--- a/src/tests/test_sequence.rs
+++ b/src/tests/test_sequence.rs
@@ -91,7 +91,7 @@ proptest! {
         let mut leaves: Vec<u32> = (0..count).collect();
         let mut rng = thread_rng();
         leaves.shuffle(&mut rng);
-        let leaves_count = rng.gen_range(1, count - 1);
+        let leaves_count = rng.gen_range(1..count - 1);
         leaves.truncate(leaves_count as usize);
         test_sequence_sub_func(count, leaves);
     }