diff --git a/Cargo.toml b/Cargo.toml
index feceae4..5c743af 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,13 +4,16 @@ description = "Integer traits and functions"
 documentation = "https://docs.rs/num-integer"
 homepage = "https://github.com/rust-num/num-integer"
 keywords = ["mathematics", "numerics"]
-categories = [ "algorithms", "science" ]
+categories = ["algorithms", "science", "no-std"]
 license = "MIT/Apache-2.0"
 repository = "https://github.com/rust-num/num-integer"
 name = "num-integer"
 version = "0.1.36"
 readme = "README.md"
 
+[package.metadata.docs.rs]
+all-features = true
+
 [dependencies.num-traits]
 version = "0.2.0"
 default-features = false
diff --git a/src/lib.rs b/src/lib.rs
index 8d47294..cd3102d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -16,9 +16,9 @@
 
 #![doc(html_root_url = "https://docs.rs/num-integer/0.1")]
 
-#![cfg_attr(not(feature = "std"), no_std)]
+#![no_std]
 #[cfg(feature = "std")]
-extern crate core;
+extern crate std;
 
 extern crate num_traits as traits;