diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 72614fa..2a83694 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -61,6 +61,10 @@ jobs:
         if: ${{ !matrix.no_std }}
         run: cargo test --verbose
 
+      - name: Cargo test no default features
+        if: matrix.nightly
+        run: cargo test --verbose --no-default-features
+
       - name: Cargo test all features
         if: matrix.nightly
         run: cargo test --verbose --all-features
@@ -69,6 +73,10 @@ jobs:
         if: matrix.nightly
         run: cargo doc --all-features --verbose
 
+      - name: Cargo bench no default features
+        if: matrix.nightly
+        run: cargo clean && cargo bench --verbose --no-default-features
+
       - name: Cargo bench all features
         if: matrix.nightly
         run: cargo clean && cargo bench --verbose --all-features
diff --git a/Cargo.lock b/Cargo.lock
index 08d6e29..a2ff25d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -20,6 +20,12 @@ dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "allocator-api2"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c880a97d28a3681c0267bd29cff89621202715b065127cd445fa0f0fe0aa2880"
+
 [[package]]
 name = "anes"
 version = "0.1.6"
@@ -639,6 +645,7 @@ checksum = "0c790de23124f9ab44544d7ac05d60440adc586479ce501c1d6d7da3cd8c9cf5"
 name = "smallvec"
 version = "2.0.0-alpha.13"
 dependencies = [
+ "allocator-api2",
  "arbitrary",
  "borsh",
  "bytes",
diff --git a/src/lib.rs b/src/lib.rs
index 6197324..2c222be 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,15 +5,14 @@
 // except according to those terms.
 
 #![doc = include_str!("../README.md")]
-#![no_std]
+#![cfg_attr(not(feature = "std"), no_std)]
 #![cfg_attr(docsrs, feature(doc_cfg))]
 #![cfg_attr(feature = "specialization", allow(incomplete_features))]
 #![cfg_attr(feature = "specialization", feature(specialization, trusted_len))]
 #![cfg_attr(feature = "may_dangle", feature(dropck_eyepatch))]
+#![cfg_attr(not(feature = "allocator-api2"), feature(allocator_api))]
 
 extern crate alloc;
-#[cfg(feature = "std")]
-extern crate std;
 
 #[cfg(feature = "borsh")]
 mod borsh;
@@ -33,7 +32,7 @@ mod specialization;
 mod taggedlen;
 
 #[cfg(not(feature = "allocator-api2"))]
-use alloc::{
+use alloc::alloc::{
     Allocator,
     Global
 };