diff --git a/Cargo.toml b/Cargo.toml
index fb8b2eb..d910d17 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,6 +3,7 @@ name = "arrayvec"
 version = "0.4.11"
 authors = ["bluss"]
 license = "MIT/Apache-2.0"
+edition = "2018"
 
 description = "A vector with fixed capacity, backed by an array (it can be stored on the stack too). Implements fixed capacity ArrayVec and ArrayString."
 documentation = "https://docs.rs/arrayvec/"
diff --git a/src/array.rs b/src/array.rs
index ed49211..ce314e7 100644
--- a/src/array.rs
+++ b/src/array.rs
@@ -26,7 +26,7 @@ pub unsafe trait Array {
 
 pub trait Index : PartialEq + Copy {
     fn to_usize(self) -> usize;
-    fn from(usize) -> Self;
+    fn from(_: usize) -> Self;
 }
 
 impl Index for () {
diff --git a/src/array_string.rs b/src/array_string.rs
index 42bb1a0..a7b4d08 100644
--- a/src/array_string.rs
+++ b/src/array_string.rs
@@ -9,10 +9,10 @@ use std::str::FromStr;
 use std::str::Utf8Error;
 use std::slice;
 
-use array::Array;
-use array::Index;
-use CapacityError;
-use char::encode_utf8;
+use crate::array::Array;
+use crate::array::Index;
+use crate::CapacityError;
+use crate::char::encode_utf8;
 
 #[cfg(feature="serde-1")]
 use serde::{Serialize, Deserialize, Serializer, Deserializer};
diff --git a/src/lib.rs b/src/lib.rs
index a04ecce..e08db68 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -48,7 +48,7 @@ use std::io;
 
 
 mod maybe_uninit;
-use maybe_uninit::MaybeUninit;
+use crate::maybe_uninit::MaybeUninit;
 
 #[cfg(feature="serde-1")]
 use serde::{Serialize, Deserialize, Serializer, Deserializer};
@@ -59,11 +59,11 @@ mod char;
 mod range;
 mod errors;
 
-pub use array::Array;
-pub use range::RangeArgument;
-use array::Index;
-pub use array_string::ArrayString;
-pub use errors::CapacityError;
+pub use crate::array::Array;
+pub use crate::range::RangeArgument;
+use crate::array::Index;
+pub use crate::array_string::ArrayString;
+pub use crate::errors::CapacityError;
 
 
 /// A vector with a fixed capacity.
diff --git a/src/maybe_uninit.rs b/src/maybe_uninit.rs
index 4903fa3..fc69a3f 100644
--- a/src/maybe_uninit.rs
+++ b/src/maybe_uninit.rs
@@ -1,6 +1,6 @@
 
 
-use array::Array;
+use crate::array::Array;
 use std::mem::MaybeUninit as StdMaybeUninit;
 
 #[derive(Copy)]
diff --git a/tests/tests.rs b/tests/tests.rs
index aa84ed4..1af779c 100644
--- a/tests/tests.rs
+++ b/tests/tests.rs
@@ -258,8 +258,8 @@ fn test_extend() {
 #[test]
 fn test_is_send_sync() {
     let data = ArrayVec::<[Vec<i32>; 5]>::new();
-    &data as &Send;
-    &data as &Sync;
+    &data as &dyn Send;
+    &data as &dyn Sync;
 }
 
 #[test]
@@ -470,7 +470,7 @@ fn test_string() {
     assert_eq!(tmut, "ab");
 
     // Test Error trait / try
-    let t = || -> Result<(), Box<Error>> {
+    let t = || -> Result<(), Box<dyn Error>> {
         let mut t = ArrayString::<[_; 2]>::new();
         t.try_push_str(text)?;
         Ok(())