diff --git a/fs_mgr/blockdev.cpp b/fs_mgr/blockdev.cpp
index 14b217c..388dadc 100644
--- a/fs_mgr/blockdev.cpp
+++ b/fs_mgr/blockdev.cpp
@@ -30,7 +30,6 @@
 using android::base::ErrnoError;
 using android::base::Error;
 using android::base::Result;
-using android::base::ResultError;
 using android::base::StartsWith;
 using android::base::StringPrintf;
 using android::base::unique_fd;
@@ -94,10 +93,8 @@
     std::string blockdev = "/dev/block/" + BlockdevName(statbuf.st_dev);
     LOG(DEBUG) << __func__ << ": " << file_path << " -> " << blockdev;
     if (blockdev.empty()) {
-        const std::string err_msg =
-                StringPrintf("Failed to convert %u:%u (path %s)", major(statbuf.st_dev),
-                             minor(statbuf.st_dev), file_path.c_str());
-        return ResultError(err_msg, 0);
+        return Errorf("Failed to convert {}:{} (path {})", major(statbuf.st_dev),
+                      minor(statbuf.st_dev), file_path.c_str());
     }
     auto& dm = DeviceMapper::Instance();
     for (;;) {
@@ -110,7 +107,7 @@
     }
     std::optional<std::string> maybe_blockdev = android::dm::ExtractBlockDeviceName(blockdev);
     if (!maybe_blockdev) {
-        return ResultError("Failed to remove /dev/block/ prefix from " + blockdev, 0);
+        return Errorf("Failed to remove /dev/block/ prefix from {}", blockdev);
     }
     blockdev = PartitionParent(*maybe_blockdev);
     LOG(DEBUG) << __func__ << ": "
@@ -119,7 +116,7 @@
             StringPrintf("/sys/class/block/%s/mq/0/nr_tags", blockdev.c_str());
     std::string nr_tags;
     if (!android::base::ReadFileToString(nr_tags_path, &nr_tags)) {
-        return ResultError("Failed to read " + nr_tags_path, 0);
+        return Errorf("Failed to read {}", nr_tags_path);
     }
     rtrim(nr_tags);
     LOG(DEBUG) << __func__ << ": " << file_path << " is backed by /dev/" << blockdev
@@ -137,11 +134,9 @@
 
     const std::string loop_device_name = Basename(loop_device_path);
 
-    const Result<uint32_t> qd = BlockDeviceQueueDepth(file_path);
+    const auto qd = BlockDeviceQueueDepth(file_path);
     if (!qd.ok()) {
-        LOG(DEBUG) << __func__ << ": "
-                   << "BlockDeviceQueueDepth() returned " << qd.error();
-        return ResultError(qd.error());
+        return qd.error();
     }
     const std::string nr_requests = StringPrintf("%u", *qd);
     const std::string sysfs_path =
diff --git a/fs_mgr/fs_mgr.cpp b/fs_mgr/fs_mgr.cpp
index a320c0e..137b066 100644
--- a/fs_mgr/fs_mgr.cpp
+++ b/fs_mgr/fs_mgr.cpp
@@ -2044,7 +2044,9 @@
 
     ConfigureIoScheduler(loop_device);
 
-    ConfigureQueueDepth(loop_device, "/");
+    if (auto ret = ConfigureQueueDepth(loop_device, "/"); !ret.ok()) {
+        LOG(DEBUG) << "Failed to config queue depth: " << ret.error().message();
+    }
 
     // set block size & direct IO
     unique_fd loop_fd(TEMP_FAILURE_RETRY(open(loop_device.c_str(), O_RDWR | O_CLOEXEC)));
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 8045c71..cc445be 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -88,6 +88,7 @@
 using namespace std::literals::string_literals;
 
 using android::base::Basename;
+using android::base::ResultError;
 using android::base::SetProperty;
 using android::base::Split;
 using android::base::StartsWith;
@@ -116,7 +117,7 @@
                         android::base::GetMinimumLogSeverity() > android::base::DEBUG) {}
 
     template <typename T>
-    operator android::base::expected<T, ResultError>() {
+    operator android::base::expected<T, ResultError<int>>() {
         if (ignore_error_) {
             return {};
         }
@@ -130,7 +131,7 @@
     }
 
   private:
-    Error error_;
+    Error<> error_;
     bool ignore_error_;
 };
 
diff --git a/init/subcontext.cpp b/init/subcontext.cpp
index 6eaa80f..7aa4a9d 100644
--- a/init/subcontext.cpp
+++ b/init/subcontext.cpp
@@ -297,7 +297,7 @@
 
     if (subcontext_reply->reply_case() == SubcontextReply::kFailure) {
         auto& failure = subcontext_reply->failure();
-        return ResultError(failure.error_string(), failure.error_errno());
+        return ResultError<>(failure.error_string(), failure.error_errno());
     }
 
     if (subcontext_reply->reply_case() != SubcontextReply::kSuccess) {
@@ -321,7 +321,7 @@
 
     if (subcontext_reply->reply_case() == SubcontextReply::kFailure) {
         auto& failure = subcontext_reply->failure();
-        return ResultError(failure.error_string(), failure.error_errno());
+        return ResultError<>(failure.error_string(), failure.error_errno());
     }
 
     if (subcontext_reply->reply_case() != SubcontextReply::kExpandArgsReply) {