diff --git a/.clang-tidy b/.clang-tidy
index ab2a8131..36586010 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -22,6 +22,7 @@ Checks:            '*,
                     -llvmlibc-restrict-system-libc-headers,
                     -misc-non-private-member-variables-in-classes,
                     -misc-use-anonymous-namespace,
+                    -misc-no-recursion,
                     -modernize-use-nodiscard,
                     -modernize-use-trailing-return-type,
                     -readability-function-cognitive-complexity,
diff --git a/src/credential.cpp b/src/credential.cpp
index f9d8016a..bb6ba3ae 100644
--- a/src/credential.cpp
+++ b/src/credential.cpp
@@ -147,6 +147,10 @@ CredentialBinding::CredentialBinding(CipherSuite cipher_suite_in,
   , credential(std::move(credential_in))
   , credential_key(credential_priv.public_key)
 {
+  if (credential.type() == CredentialType::multi_draft_00) {
+    throw InvalidParameterError("Multi-credentials cannot be nested");
+  }
+
   if (!credential.valid_for(credential_key)) {
     throw InvalidParameterError("Credential key does not match credential");
   }
diff --git a/src/treekem.cpp b/src/treekem.cpp
index 211c2f8a..92254104 100644
--- a/src/treekem.cpp
+++ b/src/treekem.cpp
@@ -531,7 +531,7 @@ TreeKEMPublicKey::parent_hash_valid() const
 }
 
 std::vector<NodeIndex>
-TreeKEMPublicKey::resolve(NodeIndex index) const // NOLINT(misc-no-recursion)
+TreeKEMPublicKey::resolve(NodeIndex index) const
 {
   auto at_leaf = (index.level() == 0);
   if (!node_at(index).blank()) {
@@ -797,7 +797,7 @@ struct TreeHashInput
 };
 
 const bytes&
-TreeKEMPublicKey::get_hash(NodeIndex index) // NOLINT(misc-no-recursion)
+TreeKEMPublicKey::get_hash(NodeIndex index)
 {
   if (hashes.count(index) > 0) {
     return hashes.at(index);
@@ -905,7 +905,6 @@ TreeKEMPublicKey::parent_hashes(
 }
 
 const bytes&
-// NOLINTNEXTLINE(misc-no-recursion)
 TreeKEMPublicKey::original_tree_hash(TreeHashCache& cache,
                                      NodeIndex index,
                                      std::vector<LeafIndex> parent_except) const