diff --git a/openmls/src/credentials/codec.rs b/openmls/src/credentials/codec.rs
index a54ae144be..f366180f74 100644
--- a/openmls/src/credentials/codec.rs
+++ b/openmls/src/credentials/codec.rs
@@ -7,9 +7,9 @@ impl tls_codec::Size for Credential {
     fn tls_serialized_len(&self) -> usize {
         self.credential_type.tls_serialized_len()
             + match &self.credential {
-                MlsCredentialType::Basic(c) => c.tls_serialized_len(),
-                MlsCredentialType::X509(c) => c.tls_serialized_len(),
-            }
+            MlsCredentialType::Basic(c) => c.tls_serialized_len(),
+            MlsCredentialType::X509(c) => c.tls_serialized_len(),
+        }
     }
 }
 
@@ -32,8 +32,7 @@ impl tls_codec::Serialize for Credential {
 impl tls_codec::Deserialize for Credential {
     fn tls_deserialize<R: Read>(bytes: &mut R) -> Result<Self, tls_codec::Error> {
         let val = u16::tls_deserialize(bytes)?;
-        let credential_type = CredentialType::try_from(val)
-            .map_err(|e| tls_codec::Error::DecodingError(e.to_string()))?;
+        let credential_type = CredentialType::from(val);
         match credential_type {
             CredentialType::Basic => Ok(Credential::from(MlsCredentialType::Basic(
                 BasicCredential::tls_deserialize(bytes)?,
diff --git a/openmls/src/credentials/mod.rs b/openmls/src/credentials/mod.rs
index 5277aed58c..a9888d5553 100644
--- a/openmls/src/credentials/mod.rs
+++ b/openmls/src/credentials/mod.rs
@@ -22,10 +22,7 @@
 //! There are multiple [`CredentialType`]s, although OpenMLS currently only
 //! supports the [`BasicCredential`].
 
-use std::{
-    convert::TryFrom,
-    io::{Read, Write},
-};
+use std::io::{Read, Write};
 
 use serde::{Deserialize, Serialize};
 use tls_codec::{TlsDeserialize, TlsSerialize, TlsSize, VLBytes};
@@ -34,6 +31,7 @@ use tls_codec::{TlsDeserialize, TlsSerialize, TlsSize, VLBytes};
 mod codec;
 #[cfg(test)]
 mod tests;
+
 use errors::*;
 use openmls_x509_credential::X509Ext;
 use x509_cert::{der::Decode, PkiPath};
@@ -93,8 +91,8 @@ impl tls_codec::Size for CredentialType {
 
 impl tls_codec::Deserialize for CredentialType {
     fn tls_deserialize<R: Read>(bytes: &mut R) -> Result<Self, tls_codec::Error>
-    where
-        Self: Sized,
+        where
+            Self: Sized,
     {
         let mut extension_type = [0u8; 2];
         bytes.read_exact(&mut extension_type)?;
@@ -162,8 +160,8 @@ impl tls_codec::Serialize for Certificate {
 
 impl tls_codec::Deserialize for Certificate {
     fn tls_deserialize<R: Read>(bytes: &mut R) -> Result<Self, tls_codec::Error>
-    where
-        Self: Sized,
+        where
+            Self: Sized,
     {
         let certificates = Vec::<Vec<u8>>::tls_deserialize(bytes)?;
         // we should not do this in a deserializer but otherwise we have to deal with a `identity: Option<Vec<u8>>` everywhere
@@ -184,7 +182,7 @@ impl Certificate {
 
     fn try_new(certificates: Vec<Vec<u8>>) -> Result<Self, CredentialError> {
         let leaf = certificates
-            .get(0)
+            .first()
             .ok_or(CredentialError::InvalidCertificateChain)?;
         let leaf = x509_cert::Certificate::from_der(leaf)?;
         let identity = leaf
@@ -201,7 +199,7 @@ impl Certificate {
 ///
 /// This enum contains variants containing the different available credentials.
 #[derive(
-    Debug, PartialEq, Eq, Clone, Serialize, Deserialize, TlsSerialize, TlsDeserialize, TlsSize,
+Debug, PartialEq, Eq, Clone, Serialize, Deserialize, TlsSerialize, TlsDeserialize, TlsSize,
 )]
 #[repr(u8)]
 pub enum MlsCredentialType {
@@ -298,7 +296,7 @@ impl From<MlsCredentialType> for Credential {
 /// OpenMLS provides an implementation of signature keys for convenience in the
 /// `openmls_basic_credential` crate.
 #[derive(
-    Debug, Clone, PartialEq, Eq, Serialize, Deserialize, TlsSerialize, TlsDeserialize, TlsSize,
+Debug, Clone, PartialEq, Eq, Serialize, Deserialize, TlsSerialize, TlsDeserialize, TlsSize,
 )]
 pub struct BasicCredential {
     identity: VLBytes,
@@ -348,7 +346,7 @@ pub mod test_utils {
             signature_scheme,
             Some(cert_data),
         )
-        .await
+            .await
     }
 
     /// Convenience function that generates a new credential and a key pair for
@@ -368,7 +366,7 @@ pub mod test_utils {
             signature_scheme,
             None,
         )
-        .await
+            .await
     }
 
     async fn build_credential(
@@ -387,7 +385,7 @@ pub mod test_utils {
             signature_scheme,
             &mut *backend.rand().borrow_rand().unwrap(),
         )
-        .unwrap();
+            .unwrap();
         signature_keys.store(backend.key_store()).await.unwrap();
 
         (
diff --git a/openmls/src/group/mod.rs b/openmls/src/group/mod.rs
index 8bce84c933..24fa8cc1c3 100644
--- a/openmls/src/group/mod.rs
+++ b/openmls/src/group/mod.rs
@@ -28,7 +28,6 @@ pub use core_group::proposals::*;
 pub use core_group::staged_commit::StagedCommit;
 pub use mls_group::config::*;
 pub use mls_group::membership::*;
-pub use mls_group::processing::*;
 pub use mls_group::*;
 pub use public_group::*;
 
diff --git a/openmls/src/prelude.rs b/openmls/src/prelude.rs
index 00999d5f54..7ec47a8c4a 100644
--- a/openmls/src/prelude.rs
+++ b/openmls/src/prelude.rs
@@ -6,7 +6,7 @@
 // MlsGroup
 pub use crate::group::{config::CryptoConfig, core_group::Member, errors::*, ser::*, *};
 
-pub use crate::group::public_group::{errors::*, process::*, *};
+pub use crate::group::public_group::errors::*;
 
 // Ciphersuite
 pub use crate::ciphersuite::{hash_ref::KeyPackageRef, signable::*, signature::*, *};
@@ -25,11 +25,8 @@ pub use crate::extensions::{errors::*, *};
 
 // Framing
 pub use crate::framing::{
-    message_in::*,
-    message_out::{MlsMessageOutBody, *},
+    message_out::MlsMessageOutBody,
     mls_content_in::FramedContentBodyIn,
-    sender::*,
-    validation::*,
     *,
 };
 
diff --git a/x509_credential/src/lib.rs b/x509_credential/src/lib.rs
index b37f806bb3..93906dedbb 100644
--- a/x509_credential/src/lib.rs
+++ b/x509_credential/src/lib.rs
@@ -35,7 +35,7 @@ impl CertificateKeyPair {
             },
         )?;
 
-        let leaf = pki_path.get(0).ok_or(CryptoError::CryptoLibraryError)?;
+        let leaf = pki_path.first().ok_or(CryptoError::CryptoLibraryError)?;
 
         let signature_scheme = leaf.signature_scheme()?;
         let pk = leaf.public_key()?;