diff --git a/src/kernel/builtin.cpp b/src/kernel/builtin.cpp
index b05bd78ed3..a7938c5aee 100644
--- a/src/kernel/builtin.cpp
+++ b/src/kernel/builtin.cpp
@@ -5,7 +5,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Author: Leonardo de Moura
 */
 #include "runtime/object.h"
-using namespace lean;
+using namespace lean; // NOLINT
 
 lean::object* lean_expr_local(lean::object*, lean::object*, lean::object*, lean::object*) {
     lean_unreachable();
diff --git a/src/library/compiler/emit_cpp.cpp b/src/library/compiler/emit_cpp.cpp
index a556321de4..b47cf84492 100644
--- a/src/library/compiler/emit_cpp.cpp
+++ b/src/library/compiler/emit_cpp.cpp
@@ -5,6 +5,8 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Author: Leonardo de Moura
 */
 #include <iostream>
+#include <limits>
+#include <string>
 #include "runtime/utf8.h"
 #include "runtime/apply.h"
 #include "kernel/instantiate.h"
@@ -651,7 +653,6 @@ struct emit_fn_fn {
             m_out << "else\n";
             emit(args[2]);
         } else {
-
             if (is_obj(x)) {
                 m_out << "switch (lean::obj_tag("; emit_fvar(x); m_out << ")) {\n";
             } else {
diff --git a/src/library/compiler/name_mangling.cpp b/src/library/compiler/name_mangling.cpp
index 5e87d0683e..a6f88ab32e 100644
--- a/src/library/compiler/name_mangling.cpp
+++ b/src/library/compiler/name_mangling.cpp
@@ -5,6 +5,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Author: Leonardo de Moura
 */
 #include <fstream>
+#include <string>
 #include "runtime/utf8.h"
 #include "util/name.h"
 
diff --git a/src/library/compiler/name_mangling.h b/src/library/compiler/name_mangling.h
index 811b88e1ba..efca5bb274 100644
--- a/src/library/compiler/name_mangling.h
+++ b/src/library/compiler/name_mangling.h
@@ -5,6 +5,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Author: Leonardo de Moura
 */
 #pragma once
+#include <string>
 #include "util/name.h"
 
 namespace lean {
diff --git a/src/library/vm/vm.cpp b/src/library/vm/vm.cpp
index d80b32b03b..08638a6008 100644
--- a/src/library/vm/vm.cpp
+++ b/src/library/vm/vm.cpp
@@ -18,7 +18,6 @@ Author: Leonardo de Moura
 #include "util/name_hash_map.h"
 #include "util/name_hash_set.h"
 #include "util/timeit.h"
-#include "util/name_hash_map.h"
 #include "util/sexpr/option_declarations.h"
 #include "util/shared_mutex.h"
 #include "library/constants.h"