diff --git a/.travis.yml b/.travis.yml
index 7451b70..72f94de 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,26 +6,26 @@ rust:
   - nightly
 
 env:
-  - TEST_COMMAND=test FEATURES=''
+  - TEST_COMMAND=test EXTRA_FLAGS='' FEATURES=''
 
 matrix:
   include:
     # We use the 64-bit optimised curve backend by default, so also test with
     # the 32-bit backend (this also exercises testing with `no_std`):
     - rust: nightly
-      env: TEST_COMMAND=build FEATURES='--no-default-features --features=u32_backend'
-    # Also test the `alloc` feature with `no_std`:
+      env: TEST_COMMAND=build EXTRA_FLAGS='--no-default-features' FEATURES='u32_backend alloc'
+    # Also test the batch feature:
     - rust: nightly
-      env: TEST_COMMAND=build FEATURES='--no-default-features --features="u64_backend alloc"'
+      env: TEST_COMMAND=build EXTRA_FLAGS='--no-default-features' FEATURES='u64_backend alloc batch'
     # Test any nightly gated features on nightly:
     - rust: nightly
-      env: TEST_COMMAND=test FEATURES='--features=nightly'
+      env: TEST_COMMAND=test EXTRA_FLAGS='' FEATURES='nightly'
     # Test serde support on stable, assuming that if it works there it'll work everywhere:
     - rust: stable
-      env: TEST_COMMAND=test FEATURE='--features=serde'
+      env: TEST_COMMAND=test EXTRA_FLAGS='' FEATURES='serde'
 
 script:
-  - cargo $TEST_COMMAND $FEATURES
+  - cargo $TEST_COMMAND --features="$FEATURES" $EXTRA_FLAGS
 
 notifications:
   slack:
diff --git a/src/ed25519.rs b/src/ed25519.rs
index 1b6334a..a76b091 100644
--- a/src/ed25519.rs
+++ b/src/ed25519.rs
@@ -93,7 +93,7 @@ pub fn verify_batch(
     public_keys: &[PublicKey],
 ) -> Result<(), SignatureError>
 {
-    const ASSERT_MESSAGE: &'static [u8] = b"The number of messages, signatures, and public keys must be equal.";
+    const ASSERT_MESSAGE: &'static str = "The number of messages, signatures, and public keys must be equal.";
     assert!(signatures.len()  == messages.len(),    ASSERT_MESSAGE);
     assert!(signatures.len()  == public_keys.len(), ASSERT_MESSAGE);
     assert!(public_keys.len() == messages.len(),    ASSERT_MESSAGE);
diff --git a/src/lib.rs b/src/lib.rs
index 1007b6c..fcd52af 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -255,6 +255,8 @@
 #[macro_use]
 extern crate std;
 
+#[cfg(all(feature = "alloc", not(feature = "std")))]
+extern crate alloc;
 extern crate clear_on_drop;
 extern crate curve25519_dalek;
 extern crate failure;