diff --git a/oss-internship-2020/libtiff/test/check_tag.cc b/oss-internship-2020/libtiff/test/check_tag.cc
index 051891b..55f2136 100644
--- a/oss-internship-2020/libtiff/test/check_tag.cc
+++ b/oss-internship-2020/libtiff/test/check_tag.cc
@@ -14,9 +14,9 @@
 
 #include "check_tag.h"  // NOLINT(build/include)
 
-using ::sapi::IsOk;
-using ::testing::Eq;
-using ::testing::IsTrue;
+#include "gtest/gtest.h"
+#include "sandboxed_api/util/status_matchers.h"
+#include "tiffio.h"  // NOLINT(build/include)
 
 void CheckShortField(TiffApi& api, sapi::v::RemotePtr& tif, const ttag_t field,
                      const uint16_t value) {
@@ -24,10 +24,10 @@ void CheckShortField(TiffApi& api, sapi::v::RemotePtr& tif, const ttag_t field,
   absl::StatusOr<int> status_or_int;
 
   status_or_int = api.TIFFGetField1(&tif, field, tmp.PtrBoth());
-  ASSERT_THAT(status_or_int, IsOk()) << "TIFFGetField1 fatal error";
-  EXPECT_THAT(status_or_int.value(), IsTrue())
+  ASSERT_THAT(status_or_int, ::sapi::IsOk()) << "TIFFGetField1 fatal error";
+  EXPECT_THAT(status_or_int.value(), ::testing::IsTrue())
       << "Problem fetching tag " << field;
-  EXPECT_THAT(tmp.GetValue(), Eq(value))
+  EXPECT_THAT(tmp.GetValue(), ::testing::Eq(value))
       << "Wrong SHORT value fetched for tag " << field;
 }
 
@@ -40,12 +40,12 @@ void CheckShortPairedField(TiffApi& api, sapi::v::RemotePtr& tif,
 
   status_or_int =
       api.TIFFGetField2(&tif, field, tmp0.PtrBoth(), tmp1.PtrBoth());
-  ASSERT_THAT(status_or_int, IsOk()) << "TIFFGetField2 fatal error";
-  EXPECT_THAT(status_or_int.value(), IsTrue())
+  ASSERT_THAT(status_or_int, ::sapi::IsOk()) << "TIFFGetField2 fatal error";
+  EXPECT_THAT(status_or_int.value(), ::testing::IsTrue())
       << "Problem fetching tag " << field;
-  EXPECT_THAT(tmp0.GetValue(), Eq(values[0]))
+  EXPECT_THAT(tmp0.GetValue(), ::testing::Eq(values[0]))
       << "Wrong SHORT PAIR[0] fetched for tag " << field;
-  EXPECT_THAT(tmp1.GetValue(), Eq(values[1]))
+  EXPECT_THAT(tmp1.GetValue(), ::testing::Eq(values[1]))
       << "Wrong SHORT PAIR[1] fetched for tag " << field;
 }
 
@@ -55,9 +55,9 @@ void CheckLongField(TiffApi& api, sapi::v::RemotePtr& tif, const ttag_t field,
   absl::StatusOr<int> status_or_int;
 
   status_or_int = api.TIFFGetField1(&tif, field, tmp.PtrBoth());
-  ASSERT_THAT(status_or_int, IsOk()) << "TIFFGetField1 fatal error";
-  EXPECT_THAT(status_or_int.value(), IsTrue())
+  ASSERT_THAT(status_or_int, ::sapi::IsOk()) << "TIFFGetField1 fatal error";
+  EXPECT_THAT(status_or_int.value(), ::testing::IsTrue())
       << "Problem fetching tag " << field;
-  EXPECT_THAT(tmp.GetValue(), Eq(value))
+  EXPECT_THAT(tmp.GetValue(), ::testing::Eq(value))
       << "Wrong LONG value fetched for tag " << field;
 }
diff --git a/oss-internship-2020/libtiff/test/check_tag.h b/oss-internship-2020/libtiff/test/check_tag.h
index b60cd74..c45c582 100644
--- a/oss-internship-2020/libtiff/test/check_tag.h
+++ b/oss-internship-2020/libtiff/test/check_tag.h
@@ -12,10 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include <cstring>
-
-#include "helper.h"  // NOLINT(build/include)
-#include "tiffio.h"  // NOLINT(build/include)
+#include "../sandboxed.h"  // NOLINT(build/include)
+#include "helper.h"        // NOLINT(build/include)
+#include "tiffio.h"        // NOLINT(build/include)
 
 void CheckShortField(TiffApi&, sapi::v::RemotePtr& tif, const ttag_t field,
                      const uint16_t value);
diff --git a/oss-internship-2020/libtiff/test/defer_strile_writing.cc b/oss-internship-2020/libtiff/test/defer_strile_writing.cc
index 017c2a8..502d1e4 100644
--- a/oss-internship-2020/libtiff/test/defer_strile_writing.cc
+++ b/oss-internship-2020/libtiff/test/defer_strile_writing.cc
@@ -12,9 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include <cstdint>
-
+#include "../sandboxed.h"  // NOLINT(build/include)
+#include "gtest/gtest.h"
 #include "helper.h"  // NOLINT(build/include)
+#include "sandboxed_api/sandbox2/util/fileops.h"
+#include "sandboxed_api/sandbox2/util/path.h"
+#include "sandboxed_api/sandbox2/util/temp_file.h"
+#include "sandboxed_api/util/status_matchers.h"
 #include "tiffio.h"  // NOLINT(build/include)
 
 namespace {
diff --git a/oss-internship-2020/libtiff/test/helper.cc b/oss-internship-2020/libtiff/test/helper.cc
index 18e1205..aec8178 100644
--- a/oss-internship-2020/libtiff/test/helper.cc
+++ b/oss-internship-2020/libtiff/test/helper.cc
@@ -14,6 +14,10 @@
 
 #include "helper.h"  // NOLINT(build/include)
 
+#include "../sandboxed.h"  // NOLINT(build/include)
+#include "sandboxed_api/sandbox2/util/fileops.h"
+#include "sandboxed_api/sandbox2/util/path.h"
+
 std::string GetImagesFolder() {
   std::string cwd = sandbox2::file_util::fileops::GetCWD();
   auto find = cwd.rfind("/build");
diff --git a/oss-internship-2020/libtiff/test/helper.h b/oss-internship-2020/libtiff/test/helper.h
index 5c920f8..b5e5afd 100644
--- a/oss-internship-2020/libtiff/test/helper.h
+++ b/oss-internship-2020/libtiff/test/helper.h
@@ -12,14 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include <optional>
 #include <string>
 
-#include "../sandboxed.h"  // NOLINT(build/include)
-#include "gtest/gtest.h"
-#include "sandboxed_api/sandbox2/util/fileops.h"
-#include "sandboxed_api/sandbox2/util/path.h"
-#include "sandboxed_api/sandbox2/util/temp_file.h"
-#include "sandboxed_api/util/status_matchers.h"
-
 std::string GetFilePath(const std::string& filename);
diff --git a/oss-internship-2020/libtiff/test/long_tag.cc b/oss-internship-2020/libtiff/test/long_tag.cc
index 5843e35..a7d1dfc 100644
--- a/oss-internship-2020/libtiff/test/long_tag.cc
+++ b/oss-internship-2020/libtiff/test/long_tag.cc
@@ -15,7 +15,12 @@
 #include <array>
 
 #include "check_tag.h"  // NOLINT(build/include)
-#include "tiffio.h"     // NOLINT(build/include)
+#include "gtest/gtest.h"
+#include "sandboxed_api/sandbox2/util/fileops.h"
+#include "sandboxed_api/sandbox2/util/path.h"
+#include "sandboxed_api/sandbox2/util/temp_file.h"
+#include "sandboxed_api/util/status_matchers.h"
+#include "tiffio.h"  // NOLINT(build/include)
 
 namespace {
 
diff --git a/oss-internship-2020/libtiff/test/raw_decode.cc b/oss-internship-2020/libtiff/test/raw_decode.cc
index 83b7edc..09aee53 100644
--- a/oss-internship-2020/libtiff/test/raw_decode.cc
+++ b/oss-internship-2020/libtiff/test/raw_decode.cc
@@ -15,9 +15,12 @@
 #include <array>
 #include <cstring>
 
+#include "../sandboxed.h"  // NOLINT(build/include)
 #include "absl/algorithm/container.h"
 #include "absl/strings/str_join.h"
+#include "gtest/gtest.h"
 #include "helper.h"  // NOLINT(build/include)
+#include "sandboxed_api/util/status_matchers.h"
 #include "tiffio.h"  // NOLINT(build/include)
 
 namespace {
diff --git a/oss-internship-2020/libtiff/test/short_tag.cc b/oss-internship-2020/libtiff/test/short_tag.cc
index f2c1d6b..091a2f8 100644
--- a/oss-internship-2020/libtiff/test/short_tag.cc
+++ b/oss-internship-2020/libtiff/test/short_tag.cc
@@ -13,10 +13,14 @@
 // limitations under the License.
 
 #include <array>
-#include <cstdint>
 
 #include "check_tag.h"  // NOLINT(build/include)
-#include "tiffio.h"     // NOLINT(build/include)
+#include "gtest/gtest.h"
+#include "sandboxed_api/sandbox2/util/fileops.h"
+#include "sandboxed_api/sandbox2/util/path.h"
+#include "sandboxed_api/sandbox2/util/temp_file.h"
+#include "sandboxed_api/util/status_matchers.h"
+#include "tiffio.h"  // NOLINT(build/include)
 
 namespace {