diff --git a/mls-rs/src/client.rs b/mls-rs/src/client.rs
index 7d85aee6..d21328e2 100644
--- a/mls-rs/src/client.rs
+++ b/mls-rs/src/client.rs
@@ -791,16 +791,17 @@ mod tests {
     };
     use assert_matches::assert_matches;
 
-    use crate::{
-        group::{
-            message_processor::ProposalMessageDescription,
-            proposal::Proposal,
-            test_utils::{test_group, test_group_custom_config},
-            ReceivedMessage,
-        },
-        psk::{ExternalPskId, PreSharedKey},
-    };
-
+    #[cfg(feature = "by_ref_proposal")]
+    use crate::group::message_processor::ProposalMessageDescription;
+    #[cfg(feature = "by_ref_proposal")]
+    use crate::group::proposal::Proposal;
+    use crate::group::test_utils::test_group;
+    #[cfg(feature = "psk")]
+    use crate::group::test_utils::test_group_custom_config;
+    #[cfg(feature = "by_ref_proposal")]
+    use crate::group::ReceivedMessage;
+    #[cfg(feature = "psk")]
+    use crate::psk::{ExternalPskId, PreSharedKey};
     use alloc::vec;
 
     #[maybe_async::test(not(mls_build_async), async(mls_build_async, crate::futures_test))]
diff --git a/mls-rs/src/group/commit.rs b/mls-rs/src/group/commit.rs
index e68f3774..f9a5fa3c 100644
--- a/mls-rs/src/group/commit.rs
+++ b/mls-rs/src/group/commit.rs
@@ -2,6 +2,7 @@
 // Copyright by contributors to this project.
 // SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
+use alloc::boxed::Box;
 use alloc::vec;
 use alloc::vec::Vec;
 use core::fmt::Debug;
@@ -614,7 +615,7 @@ where
             &self.cipher_suite_provider,
             self.context(),
             sender,
-            Content::Commit(alloc::boxed::Box::new(commit)),
+            Content::Commit(Box::new(commit)),
             old_signer,
             #[cfg(feature = "private_message")]
             self.encryption_options()?.control_wire_format(sender),
@@ -879,8 +880,6 @@ pub(crate) mod test_utils {
 
 #[cfg(test)]
 mod tests {
-    use alloc::boxed::Box;
-
     use mls_rs_core::{
         error::IntoAnyError,
         extension::ExtensionType,
@@ -888,19 +887,7 @@ mod tests {
         time::MlsTime,
     };
 
-    use crate::{
-        crypto::test_utils::{test_cipher_suite_provider, TestCryptoProvider},
-        group::{
-            mls_rules::DefaultMlsRules,
-            test_utils::{test_group, test_group_custom},
-        },
-        mls_rules::CommitOptions,
-        Client,
-    };
-
-    #[cfg(feature = "by_ref_proposal")]
-    use crate::extension::ExternalSendersExt;
-
+    use crate::extension::RequiredCapabilitiesExt;
     use crate::{
         client::test_utils::{test_client_with_key_pkg, TEST_CIPHER_SUITE, TEST_PROTOCOL_VERSION},
         client_builder::{
@@ -908,7 +895,9 @@ mod tests {
             WithIdentityProvider,
         },
         client_config::ClientConfig,
+        crypto::test_utils::TestCryptoProvider,
         extension::test_utils::{TestExtension, TEST_EXTENSION_TYPE},
+        group::test_utils::{test_group, test_group_custom},
         group::{
             proposal::ProposalType,
             test_utils::{test_group_custom_config, test_n_member_group},
@@ -916,9 +905,16 @@ mod tests {
         identity::test_utils::get_test_signing_identity,
         identity::{basic::BasicIdentityProvider, test_utils::get_test_basic_credential},
         key_package::test_utils::test_key_package_message,
+        mls_rules::CommitOptions,
+        Client,
     };
 
-    use crate::extension::RequiredCapabilitiesExt;
+    #[cfg(feature = "by_ref_proposal")]
+    use crate::crypto::test_utils::test_cipher_suite_provider;
+    #[cfg(feature = "by_ref_proposal")]
+    use crate::extension::ExternalSendersExt;
+    #[cfg(feature = "by_ref_proposal")]
+    use crate::group::mls_rules::DefaultMlsRules;
 
     #[cfg(feature = "psk")]
     use crate::{
diff --git a/mls-rs/src/group/message_verifier.rs b/mls-rs/src/group/message_verifier.rs
index 5845ba12..a29c0c98 100644
--- a/mls-rs/src/group/message_verifier.rs
+++ b/mls-rs/src/group/message_verifier.rs
@@ -213,6 +213,7 @@ fn signing_identity_for_new_member_proposal(
 
 #[cfg(test)]
 mod tests {
+    use super::*;
     use crate::{
         client::{
             test_utils::{test_client_with_key_pkg, TEST_CIPHER_SUITE, TEST_PROTOCOL_VERSION},
@@ -226,7 +227,6 @@ mod tests {
             test_utils::{test_group_custom, TestGroup},
             Group, PublicMessage,
         },
-        tree_kem::node::LeafIndex,
     };
     use alloc::vec;
     use assert_matches::assert_matches;
@@ -250,6 +250,7 @@ mod tests {
     #[cfg(feature = "by_ref_proposal")]
     use alloc::boxed::Box;
 
+    #[cfg(feature = "by_ref_proposal")]
     use crate::group::{
         test_utils::{test_group, test_member},
         Sender,
@@ -258,8 +259,6 @@ mod tests {
     #[cfg(feature = "by_ref_proposal")]
     use crate::identity::test_utils::get_test_signing_identity;
 
-    use super::{verify_auth_content_signature, verify_plaintext_authentication};
-
     #[cfg_attr(not(mls_build_async), maybe_async::must_be_sync)]
     async fn make_signed_plaintext(group: &mut Group<TestClientConfig>) -> PublicMessage {
         group
diff --git a/mls-rs/src/group/mod.rs b/mls-rs/src/group/mod.rs
index 25b6b856..b90b5b00 100644
--- a/mls-rs/src/group/mod.rs
+++ b/mls-rs/src/group/mod.rs
@@ -1898,19 +1898,12 @@ pub(crate) mod test_utils;
 mod tests {
     use crate::{
         client::test_utils::{
-            test_client_with_key_pkg, test_client_with_key_pkg_custom, TestClientBuilder,
-            TEST_CIPHER_SUITE, TEST_CUSTOM_PROPOSAL_TYPE, TEST_PROTOCOL_VERSION,
+            test_client_with_key_pkg, TestClientBuilder, TEST_CIPHER_SUITE, TEST_PROTOCOL_VERSION,
         },
-        client_builder::{test_utils::TestClientConfig, ClientBuilder, MlsConfig},
+        client_builder::test_utils::TestClientConfig,
         crypto::test_utils::TestCryptoProvider,
-        group::{
-            mls_rules::{CommitDirection, CommitSource},
-            proposal_filter::{ProposalBundle, ProposalInfo},
-        },
-        identity::{
-            basic::BasicIdentityProvider,
-            test_utils::{get_test_signing_identity, BasicWithCustomProvider},
-        },
+        group::proposal_filter::ProposalInfo,
+        identity::test_utils::get_test_signing_identity,
         key_package::test_utils::test_key_package_message,
         mls_rules::CommitOptions,
         tree_kem::{
@@ -1919,6 +1912,18 @@ mod tests {
         },
     };
 
+    #[cfg(feature = "by_ref_proposal")]
+    use crate::{
+        client::test_utils::{test_client_with_key_pkg_custom, TEST_CUSTOM_PROPOSAL_TYPE},
+        client_builder::{ClientBuilder, MlsConfig},
+        group::{
+            mls_rules::{CommitDirection, CommitSource},
+            proposal_filter::ProposalBundle,
+        },
+        identity::basic::BasicIdentityProvider,
+        identity::test_utils::BasicWithCustomProvider,
+    };
+
     #[cfg(any(feature = "private_message", feature = "custom_proposal"))]
     use crate::group::mls_rules::DefaultMlsRules;
 
diff --git a/mls-rs/src/identity.rs b/mls-rs/src/identity.rs
index cd50e2d4..58bf7c25 100644
--- a/mls-rs/src/identity.rs
+++ b/mls-rs/src/identity.rs
@@ -17,6 +17,7 @@ pub use mls_rs_core::identity::{
 
 #[cfg(test)]
 pub(crate) mod test_utils {
+    #[cfg(feature = "std")]
     use alloc::boxed::Box;
     use alloc::vec;
     use alloc::vec::Vec;
diff --git a/mls-rs/src/tree_kem/interop_test_vectors.rs b/mls-rs/src/tree_kem/interop_test_vectors.rs
index 50e0077a..7020eb3c 100644
--- a/mls-rs/src/tree_kem/interop_test_vectors.rs
+++ b/mls-rs/src/tree_kem/interop_test_vectors.rs
@@ -2,20 +2,27 @@
 // Copyright by contributors to this project.
 // SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
+#[cfg(feature = "rfc_compliant")]
 use alloc::vec;
 use alloc::vec::Vec;
-use mls_rs_codec::{MlsDecode, MlsEncode};
-use mls_rs_core::crypto::{CipherSuite, CipherSuiteProvider};
+#[cfg(feature = "rfc_compliant")]
+use mls_rs_codec::MlsDecode;
+use mls_rs_codec::MlsEncode;
+#[cfg(feature = "rfc_compliant")]
+use mls_rs_core::crypto::CipherSuite;
+use mls_rs_core::crypto::CipherSuiteProvider;
 
+#[cfg(feature = "rfc_compliant")]
 use itertools::Itertools;
 
+#[cfg(feature = "rfc_compliant")]
 use crate::{
     crypto::test_utils::try_test_cipher_suite_provider, identity::basic::BasicIdentityProvider,
 };
 
-use super::{
-    node::NodeVec, test_utils::TreeWithSigners, tree_validator::TreeValidator, TreeKemPublic,
-};
+use super::TreeKemPublic;
+#[cfg(feature = "rfc_compliant")]
+use super::{node::NodeVec, test_utils::TreeWithSigners, tree_validator::TreeValidator};
 
 #[derive(serde::Serialize, serde::Deserialize, Debug, Default, Clone)]
 struct ValidationTestCase {
diff --git a/mls-rs/src/tree_kem/leaf_node_validator.rs b/mls-rs/src/tree_kem/leaf_node_validator.rs
index 17742ec7..442b3d83 100644
--- a/mls-rs/src/tree_kem/leaf_node_validator.rs
+++ b/mls-rs/src/tree_kem/leaf_node_validator.rs
@@ -625,8 +625,10 @@ mod tests {
 
 #[cfg(test)]
 pub(crate) mod test_utils {
+    #[cfg(feature = "std")]
+    use alloc::boxed::Box;
     use alloc::vec;
-    use alloc::{boxed::Box, vec::Vec};
+    use alloc::vec::Vec;
     use mls_rs_codec::MlsEncode;
     use mls_rs_core::{
         error::IntoAnyError,