diff --git a/.github/workflows/build_pyvelox.yml b/.github/workflows/build_pyvelox.yml
index 5a397f431580..2cc709875d2e 100644
--- a/.github/workflows/build_pyvelox.yml
+++ b/.github/workflows/build_pyvelox.yml
@@ -48,7 +48,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [8-core-ubuntu, macos-13, macos-14]
+        os: [8-core-ubuntu, macos-15-intel, macos-15]
     steps:
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
         with:
@@ -83,6 +83,7 @@ jobs:
           echo "CMAKE_PREFIX_PATH=$INSTALL_PREFIX" >> $GITHUB_ENV
           echo "INSTALL_PREFIX=$INSTALL_PREFIX" >> $GITHUB_ENV
           echo "DYLD_LIBRARY_PATH=$INSTALL_PREFIX/lib:$DYLD_LIBRARY_PATH" >> $GITHUB_ENV
+          echo "$INSTALL_PREFIX/bin" >> "$GITHUB_PATH"
 
           source scripts/setup-macos.sh
           install_build_prerequisites
diff --git a/velox/expression/VectorReaders.h b/velox/expression/VectorReaders.h
index eb1e683da580..1411bcd33cc2 100644
--- a/velox/expression/VectorReaders.h
+++ b/velox/expression/VectorReaders.h
@@ -115,7 +115,7 @@ struct ConstantVectorReader {
 
   std::optional<exec_in_t> value;
 
-  explicit ConstantVectorReader<T>(ConstantVector<exec_in_t>& vector) {
+  explicit ConstantVectorReader(ConstantVector<exec_in_t>& vector) {
     if (!vector.isNullAt(0)) {
       value = *vector.rawValues();
     }
@@ -160,7 +160,7 @@ struct FlatVectorReader {
   const exec_in_t* values;
   FlatVector<exec_in_t>* vector;
 
-  explicit FlatVectorReader<T>(FlatVector<exec_in_t>& baseVector)
+  explicit FlatVectorReader(FlatVector<exec_in_t>& baseVector)
       : values(baseVector.rawValues()), vector(&baseVector) {}
 
   exec_in_t operator[](vector_size_t offset) const {
diff --git a/velox/functions/sparksql/tests/ToJsonTest.cpp b/velox/functions/sparksql/tests/ToJsonTest.cpp
index 9ce1959cc201..dbcb54c256bc 100644
--- a/velox/functions/sparksql/tests/ToJsonTest.cpp
+++ b/velox/functions/sparksql/tests/ToJsonTest.cpp
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 #include "velox/common/base/tests/GTestUtils.h"
+#include "velox/common/testutil/OptionalEmpty.h"
 #include "velox/functions/sparksql/tests/JsonTestUtil.h"
 
 using namespace facebook::velox::test;
@@ -53,9 +54,9 @@ TEST_F(ToJsonTest, basicStruct) {
 
 TEST_F(ToJsonTest, basicArray) {
   auto input = makeNullableArrayVector<int64_t>(
-      {{{1}},
-       {{2, std::nullopt, 3}},
-       {std::vector<std::optional<int64_t>>{}},
+      {std::vector<std::optional<int64_t>>{1},
+       std::vector<std::optional<int64_t>>{2, std::nullopt, 3},
+       common::testutil::optionalEmpty,
        std::nullopt});
   auto expected = makeNullableFlatVector<std::string>(
       {R"([1])", R"([2,null,3])", R"([])", std::nullopt});
@@ -65,20 +66,24 @@ TEST_F(ToJsonTest, basicArray) {
 TEST_F(ToJsonTest, basicMap) {
   // MAP(VARCHAR, BIGINT)
   auto input = makeNullableMapVector<std::string, int64_t>(
-      {{{{"a", 1}, {"b", 2}, {"c", 3}}},
+      {std::vector<std::pair<std::string, std::optional<int64_t>>>{
+           {"a", 1}, {"b", 2}, {"c", 3}},
        std::nullopt,
-       {std::vector<std::pair<std::string, std::optional<int64_t>>>{}},
-       {{{"a", 1}, {"b", std::nullopt}}}});
+       common::testutil::optionalEmpty,
+       std::vector<std::pair<std::string, std::optional<int64_t>>>{
+           {"a", 1}, {"b", std::nullopt}}});
   auto expected = makeNullableFlatVector<std::string>(
       {R"({"a":1,"b":2,"c":3})", std::nullopt, R"({})", R"({"a":1,"b":null})"});
   testToJson(input, expected);
 
   // MAP(BIGINT, VARCHAR)
   input = makeNullableMapVector<int64_t, std::string>(
-      {{{{1, "a"}, {2, "b"}, {3, "c"}}},
+      {std::vector<std::pair<int64_t, std::optional<std::string>>>{
+           {1, "a"}, {2, "b"}, {3, "c"}},
        std::nullopt,
-       {std::vector<std::pair<int64_t, std::optional<std::string>>>{}},
-       {{{1, "a"}, {2, std::nullopt}}}});
+       common::testutil::optionalEmpty,
+       std::vector<std::pair<int64_t, std::optional<std::string>>>{
+           {1, "a"}, {2, std::nullopt}}});
   expected = makeNullableFlatVector<std::string>(
       {R"({"1":"a","2":"b","3":"c"})",
        std::nullopt,
@@ -284,10 +289,10 @@ TEST_F(ToJsonTest, nestedMap) {
   auto data1 = makeNullableFlatVector<int32_t>(
       {0, 18321, -25567, 2932896, std::nullopt}, DateType::get());
   auto data2 = makeNullableArrayVector<std::string>(
-      {{{"a", "b", std::nullopt}},
-       {std::vector<std::optional<std::string>>{}},
-       {{"d", "e"}},
-       {{"f", std::nullopt, "h"}},
+      {std::vector<std::optional<std::string>>{"a", "b", std::nullopt},
+       common::testutil::optionalEmpty,
+       std::vector<std::optional<std::string>>{"d", "e"},
+       std::vector<std::optional<std::string>>{"f", std::nullopt, "h"},
        std::nullopt});
   auto data3 = makeNullableFlatVector<double>(
       {1.0, kNaNDouble, kInfDouble, -kInfDouble, std::nullopt});
diff --git a/velox/vector/tests/FlatMapVectorTest.cpp b/velox/vector/tests/FlatMapVectorTest.cpp
index 651834074d3e..bfe88b62da8f 100644
--- a/velox/vector/tests/FlatMapVectorTest.cpp
+++ b/velox/vector/tests/FlatMapVectorTest.cpp
@@ -17,9 +17,9 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
-#include "velox/common/base/VeloxException.h"
 #include "velox/common/base/tests/GTestUtils.h"
 #include "velox/common/memory/Memory.h"
+#include "velox/common/testutil/OptionalEmpty.h"
 #include "velox/vector/tests/utils/VectorMaker.h"
 #include "velox/vector/tests/utils/VectorTestBase.h"
 
@@ -443,17 +443,14 @@ TEST_F(FlatMapVectorTest, sortedKeyIndices) {
 }
 
 TEST_F(FlatMapVectorTest, toString) {
-  auto vector = maker_.flatMapVectorNullable<int64_t, int64_t>({
-      std::optional{std::vector<std::pair<int64_t, std::optional<int64_t>>>{}},
-      std::optional<std::vector<std::pair<int64_t, std::optional<int64_t>>>>{
-          std::nullopt},
-      std::optional<std::vector<std::pair<int64_t, std::optional<int64_t>>>>{
-          {{1, {0}}}},
-      std::optional<std::vector<std::pair<int64_t, std::optional<int64_t>>>>{
-          {{1, {1}}, {2, {std::nullopt}}}},
-      std::optional<std::vector<std::pair<int64_t, std::optional<int64_t>>>>{
-          {{0, {0}}, {1, {1}}, {2, {2}}, {3, {3}}, {4, {4}}, {5, {5}}}},
-  });
+  auto vector = maker_.flatMapVectorNullable<int64_t, int64_t>(
+      {common::testutil::optionalEmpty,
+       std::nullopt,
+       std::vector<std::pair<int64_t, std::optional<int64_t>>>{{1, 0}},
+       std::vector<std::pair<int64_t, std::optional<int64_t>>>{
+           {1, 1}, {2, std::nullopt}},
+       std::vector<std::pair<int64_t, std::optional<int64_t>>>{
+           {0, 0}, {1, 1}, {2, 2}, {3, 3}, {4, 4}, {5, 5}}});
 
   EXPECT_EQ(
       vector->toString(), "[FLAT_MAP MAP<BIGINT,BIGINT>: 5 elements, 1 nulls]");