import collections from alloc

traits/src/error.rs

@@ -2,6 +2,7 @@
 //!
 //! Errors thrown by crypto functions implementing the [`crate::HpkeCrypto`] traits.
 
+use alloc::string::String;
 use core::fmt::Display;
 
 /// Errors thrown by [`crate::HpkeCrypto`] trait implementations.

traits/src/lib.rs

@@ -1,4 +1,12 @@
 #![doc = include_str!("../Readme.md")]
+#![no_std]
+
+extern crate alloc;
+#[cfg(feature = "std")]
+extern crate std;
+
+use alloc::string::String;
+use alloc::vec::Vec;
 
 use error::Error;
 use types::{AeadAlgorithm, KemAlgorithm};