diff --git a/src/processor/extract_schema.cpp b/src/processor/extract_schema.cpp
index d77365973..ade38651f 100644
--- a/src/processor/extract_schema.cpp
+++ b/src/processor/extract_schema.cpp
@@ -221,10 +221,11 @@ owned_object node_serialize::operator()(const node_array_ptr &node) const
     }
 
     if (node->truncated) {
-        array.emplace_back(
-            object_builder::map({{"len", node->length}, {"truncated", true}}, alloc));
+        array.emplace_back(object_builder::map(
+            {{"len", static_cast<uint64_t>(node->length)}, {"truncated", true}}, alloc));
     } else {
-        array.emplace_back(object_builder::map({{"len", node->length}}, alloc));
+        array.emplace_back(
+            object_builder::map({{"len", static_cast<uint64_t>(node->length)}}, alloc));
     }
 
     return array;
diff --git a/src/transformer/base64_encode.cpp b/src/transformer/base64_encode.cpp
index 897d51293..0b70c1433 100644
--- a/src/transformer/base64_encode.cpp
+++ b/src/transformer/base64_encode.cpp
@@ -42,10 +42,12 @@ bool base64_encode::transform_impl(cow_string &str)
     cow_string::size_type write = 0;
 
     for (; read + 2 < str.length(); read += 3) {
-        const std::array<uint8_t, 4> quartet{str.at<uint8_t>(read) >> 2,
-            (str.at<uint8_t>(read) & 0x3) << 4 | (str.at<uint8_t>(read + 1) >> 4),
-            (str.at<uint8_t>(read + 1) & 0xf) << 2 | str.at<uint8_t>(read + 2) >> 6,
-            str.at<uint8_t>(read + 2) & 0x3f};
+        const std::array<uint8_t, 4> quartet{static_cast<uint8_t>(str.at<uint8_t>(read) >> 2),
+            static_cast<uint8_t>(
+                (str.at<uint8_t>(read) & 0x3) << 4 | (str.at<uint8_t>(read + 1) >> 4)),
+            static_cast<uint8_t>(
+                (str.at<uint8_t>(read + 1) & 0xf) << 2 | str.at<uint8_t>(read + 2) >> 6),
+            static_cast<uint8_t>(str.at<uint8_t>(read + 2) & 0x3f)};
 
         new_string[write++] = b64Encoding[quartet[0]];
         new_string[write++] = b64Encoding[quartet[1]];