diff --git a/test/tools/ossfuzz/CMakeLists.txt b/test/tools/ossfuzz/CMakeLists.txt
index 83543b9f0..0e4c1456a 100644
--- a/test/tools/ossfuzz/CMakeLists.txt
+++ b/test/tools/ossfuzz/CMakeLists.txt
@@ -10,7 +10,11 @@ add_dependencies(ossfuzz
 
 if (OSSFUZZ)
     add_custom_target(ossfuzz_proto)
-    add_dependencies(ossfuzz_proto yul_proto_ossfuzz yul_proto_diff_ossfuzz)
+    add_dependencies(ossfuzz_proto
+            yul_proto_ossfuzz
+            yul_proto_diff_ossfuzz
+            yul_proto_diff_custom_mutate_ossfuzz
+    )
 
     add_custom_target(ossfuzz_abiv2)
     add_dependencies(ossfuzz_abiv2 abiv2_proto_ossfuzz)
@@ -60,6 +64,22 @@ if (OSSFUZZ)
     )
     set_target_properties(yul_proto_diff_ossfuzz PROPERTIES LINK_FLAGS ${LIB_FUZZING_ENGINE})
 
+    add_executable(yul_proto_diff_custom_mutate_ossfuzz
+            yulProto_diff_ossfuzz.cpp
+            yulFuzzerCommon.cpp
+            protoToYul.cpp
+            yulProto.pb.cc
+            protomutators/YulProtoMutator.cpp
+            )
+    target_include_directories(yul_proto_diff_custom_mutate_ossfuzz PRIVATE /usr/include/libprotobuf-mutator)
+    target_link_libraries(yul_proto_diff_custom_mutate_ossfuzz PRIVATE yul
+            yulInterpreter
+            protobuf-mutator-libfuzzer.a
+            protobuf-mutator.a
+            protobuf.a
+            )
+    set_target_properties(yul_proto_diff_custom_mutate_ossfuzz PROPERTIES LINK_FLAGS ${LIB_FUZZING_ENGINE})
+
     add_executable(abiv2_proto_ossfuzz
             ../../EVMHost.cpp
             abiV2ProtoFuzzer.cpp
diff --git a/test/tools/ossfuzz/protomutators/YulProtoMutator.cpp b/test/tools/ossfuzz/protomutators/YulProtoMutator.cpp
new file mode 100644
index 000000000..4765ccd7f
--- /dev/null
+++ b/test/tools/ossfuzz/protomutators/YulProtoMutator.cpp
@@ -0,0 +1,150 @@
+#include <test/tools/ossfuzz/protomutators/YulProtoMutator.h>
+
+#include <src/text_format.h>
+
+#define DEBUG
+
+using namespace yul::test::yul_fuzzer;
+
+/// Invert condition of an if statement
+static YulProtoMutator invertIfCondition(
+	IfStmt::descriptor(),
+	[](google::protobuf::Message* _message, unsigned int _seed)
+	{
+		IfStmt* ifStmt = static_cast<IfStmt*>(_message);
+		if (_seed % YulProtoMutator::s_mediumIP == 0)
+		{
+			if (ifStmt->has_cond())
+			{
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+				std::cout << "YULMUTATOR: If condition inverted" << std::endl;
+#endif
+				UnaryOp* notOp = new UnaryOp();
+				notOp->set_op(UnaryOp::NOT);
+				Expression *oldCond = ifStmt->release_cond();
+				notOp->set_allocated_operand(oldCond);
+				Expression *ifCond = new Expression();
+				ifCond->set_allocated_unop(notOp);
+				ifStmt->set_allocated_cond(ifCond);
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+#endif
+			}
+		}
+	}
+);
+
+/// Add break statement in body of a for-loop statement
+static YulProtoMutator addBreak(
+	ForStmt::descriptor(),
+	[](google::protobuf::Message* _message, unsigned int _seed)
+	{
+		ForStmt* forStmt = static_cast<ForStmt*>(_message);
+		if (_seed % YulProtoMutator::s_mediumIP == 0)
+		{
+			if (forStmt->has_for_body())
+			{
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+				std::cout << "YULMUTATOR: Break added" << std::endl;
+#endif
+				BreakStmt* breakStmt = new BreakStmt();
+				Statement* statement = forStmt->mutable_for_body()->add_statements();
+				statement->clear_stmt_oneof();
+				statement->set_allocated_breakstmt(breakStmt);
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+#endif
+			}
+		}
+	}
+);
+
+/// Add break statement in body of a for-loop statement
+static YulProtoMutator addContinue(
+	ForStmt::descriptor(),
+	[](google::protobuf::Message* _message, unsigned int _seed)
+	{
+		ForStmt* forStmt = static_cast<ForStmt*>(_message);
+		if (_seed % YulProtoMutator::s_mediumIP == 0)
+		{
+			if (forStmt->has_for_body())
+			{
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+				std::cout << "YULMUTATOR: Continue added" << std::endl;
+#endif
+				ContinueStmt* contStmt = new ContinueStmt();
+				Statement* statement = forStmt->mutable_for_body()->add_statements();
+				statement->clear_stmt_oneof();
+				statement->set_allocated_contstmt(contStmt);
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+#endif
+			}
+		}
+	}
+);
+
+/// Add declaration statement referencing mload(0)
+static YulProtoMutator addMloadZero(
+	VarDecl::descriptor(),
+	[](google::protobuf::Message* _message, unsigned int _seed)
+	{
+		VarDecl* varDeclStmt = static_cast<VarDecl*>(_message);
+		if (_seed % YulProtoMutator::s_mediumIP == 0)
+		{
+			if (varDeclStmt->has_expr())
+			{
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+				std::cout << "YULMUTATOR: mload added" << std::endl;
+#endif
+				varDeclStmt->clear_expr();
+				Literal *zeroLit = new Literal();
+				zeroLit->set_intval(0);
+				Expression *consExpr = new Expression();
+				consExpr->set_allocated_cons(zeroLit);
+				UnaryOp *mloadOp = new UnaryOp();
+				mloadOp->set_op(UnaryOp::MLOAD);
+				mloadOp->set_allocated_operand(consExpr);
+				Expression *mloadExpr = new Expression();
+				mloadExpr->set_allocated_unop(mloadOp);
+				varDeclStmt->set_allocated_expr(mloadExpr);
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+#endif
+			}
+		}
+	}
+);
+
+/// Invert condition of a for statement
+static YulProtoMutator invertForCondition(
+	ForStmt::descriptor(),
+	[](google::protobuf::Message* _message, unsigned int _seed)
+	{
+		ForStmt* forStmt = static_cast<ForStmt*>(_message);
+		if (_seed % YulProtoMutator::s_mediumIP == 0)
+		{
+			if (forStmt->has_for_cond())
+			{
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+				std::cout << "YULMUTATOR: For condition inverted" << std::endl;
+#endif
+				UnaryOp* notOp = new UnaryOp();
+				notOp->set_op(UnaryOp::NOT);
+				Expression *oldCond = forStmt->release_for_cond();
+				notOp->set_allocated_operand(oldCond);
+				Expression *forCond = new Expression();
+				forCond->set_allocated_unop(notOp);
+				forStmt->set_allocated_for_cond(forCond);
+#ifdef DEBUG
+//				std::cout << protobuf_mutator::SaveMessageAsText(*_message) << std::endl;
+#endif
+			}
+		}
+	}
+);
\ No newline at end of file
diff --git a/test/tools/ossfuzz/protomutators/YulProtoMutator.h b/test/tools/ossfuzz/protomutators/YulProtoMutator.h
new file mode 100644
index 000000000..ed2798449
--- /dev/null
+++ b/test/tools/ossfuzz/protomutators/YulProtoMutator.h
@@ -0,0 +1,32 @@
+#pragma once
+
+#include <test/tools/ossfuzz/yulProto.pb.h>
+
+#include <src/libfuzzer/libfuzzer_macro.h>
+
+namespace yul
+{
+namespace test
+{
+namespace yul_fuzzer
+{
+struct YulProtoMutator
+{
+	YulProtoMutator(
+		google::protobuf::Descriptor const* _desc,
+		std::function<void(google::protobuf::Message*, unsigned int)> _callback
+	)
+	{
+		protobuf_mutator::libfuzzer::RegisterPostProcessor(_desc, _callback);
+	}
+
+	static constexpr unsigned s_lowIP = 41;
+	static constexpr unsigned s_mediumIP = 29;
+	static constexpr unsigned s_highIP = 17;
+};
+
+
+
+}
+}
+}
\ No newline at end of file