diff --git a/src/lib.rs b/src/lib.rs
index 15146f2..13d261b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -253,6 +253,13 @@
 #![warn(rust_2018_idioms)]
 #![deny(missing_docs)] // refuse to compile if documentation is missing
 
+#[cfg(any(feature = "std", test))]
+#[macro_use]
+extern crate std;
+
+#[cfg(feature = "alloc")]
+#[macro_use]
+extern crate alloc;
 
 extern crate curve25519_dalek;
 extern crate merlin;
@@ -264,16 +271,11 @@ extern crate rand_chacha;
 
 extern crate failure;
 
+extern crate ed25519_dalek;
 
 #[cfg(test)]
 extern crate sha3;
 
-extern crate ed25519_dalek;
-
-#[cfg(any(feature = "std", test))]
-#[macro_use]
-extern crate std;
-
 extern crate sha2;
 
 // #[cfg(test)]
diff --git a/src/musig.rs b/src/musig.rs
index 222bb23..b0ebc60 100644
--- a/src/musig.rs
+++ b/src/musig.rs
@@ -34,10 +34,9 @@
 use core::borrow::{Borrow};  // BorrowMut
 
 #[cfg(feature = "alloc")]
-use alloc::collections::{BTreeMap, btree_map::Entry};
+use alloc::{collections::btree_map::{BTreeMap, Entry}};
 #[cfg(feature = "std")]
-use std::collections::{BTreeMap, btree_map::Entry};
-
+use std::{collections::btree_map::{BTreeMap, Entry}};
 
 use merlin::Transcript;
 use clear_on_drop::clear::Clear;
diff --git a/src/sign.rs b/src/sign.rs
index b3e62e8..fb5d40d 100644
--- a/src/sign.rs
+++ b/src/sign.rs
@@ -265,7 +265,7 @@ where
     T: SigningTranscript, 
     I: IntoIterator<Item=T>,
 {
-    const ASSERT_MESSAGE: &'static [u8] = b"The number of messages/transcripts, signatures, and public keys must be equal.";
+    const ASSERT_MESSAGE: &'static str = "The number of messages/transcripts, signatures, and public keys must be equal.";
     assert!(signatures.len() == public_keys.len(), ASSERT_MESSAGE);  // Check transcripts length below
 
     #[cfg(feature = "alloc")]
diff --git a/src/vrf.rs b/src/vrf.rs
index fd46070..da02463 100644
--- a/src/vrf.rs
+++ b/src/vrf.rs
@@ -801,7 +801,7 @@ pub fn dleq_verify_batch(
 ) -> bool {
     use curve25519_dalek::traits::IsIdentity;
 
-    const ASSERT_MESSAGE: &'static [u8] = b"The number of messages/transcripts / input points, output points, proofs, and public keys must be equal.";
+    const ASSERT_MESSAGE: &'static str = "The number of messages/transcripts / input points, output points, proofs, and public keys must be equal.";
     assert!(ps.len() == proofs.len(), ASSERT_MESSAGE);
     assert!(proofs.len() == public_keys.len(), ASSERT_MESSAGE);