diff --git a/cmds/idmap2/include/idmap2/BinaryStreamVisitor.h b/cmds/idmap2/include/idmap2/BinaryStreamVisitor.h
index 5e189f2..7b38bd1 100644
--- a/cmds/idmap2/include/idmap2/BinaryStreamVisitor.h
+++ b/cmds/idmap2/include/idmap2/BinaryStreamVisitor.h
@@ -39,7 +39,7 @@
   void Write8(uint8_t value);
   void Write16(uint16_t value);
   void Write32(uint32_t value);
-  void WriteString(const StringPiece& value);
+  void WriteString(StringPiece value);
   std::ostream& stream_;
 };
 
diff --git a/cmds/idmap2/libidmap2/BinaryStreamVisitor.cpp b/cmds/idmap2/libidmap2/BinaryStreamVisitor.cpp
index 4b271a1..8976924 100644
--- a/cmds/idmap2/libidmap2/BinaryStreamVisitor.cpp
+++ b/cmds/idmap2/libidmap2/BinaryStreamVisitor.cpp
@@ -38,7 +38,7 @@
   stream_.write(reinterpret_cast<char*>(&x), sizeof(uint32_t));
 }
 
-void BinaryStreamVisitor::WriteString(const StringPiece& value) {
+void BinaryStreamVisitor::WriteString(StringPiece value) {
   // pad with null to nearest word boundary;
   size_t padding_size = CalculatePadding(value.size());
   Write32(value.size());
diff --git a/cmds/idmap2/libidmap2/FabricatedOverlay.cpp b/cmds/idmap2/libidmap2/FabricatedOverlay.cpp
index d517e29..dd5be21c 100644
--- a/cmds/idmap2/libidmap2/FabricatedOverlay.cpp
+++ b/cmds/idmap2/libidmap2/FabricatedOverlay.cpp
@@ -101,10 +101,10 @@
 }
 
 Result<FabricatedOverlay> FabricatedOverlay::Builder::Build() {
-  using ConfigMap = std::map<std::string, TargetValue>;
-  using EntryMap = std::map<std::string, ConfigMap>;
-  using TypeMap = std::map<std::string, EntryMap>;
-  using PackageMap = std::map<std::string, TypeMap>;
+  using ConfigMap = std::map<std::string, TargetValue, std::less<>>;
+  using EntryMap = std::map<std::string, ConfigMap, std::less<>>;
+  using TypeMap = std::map<std::string, EntryMap, std::less<>>;
+  using PackageMap = std::map<std::string, TypeMap, std::less<>>;
   PackageMap package_map;
   android::StringPool string_pool;
   for (const auto& res_entry : entries_) {
@@ -116,8 +116,7 @@
       return Error("failed to parse resource name '%s'", res_entry.resource_name.c_str());
     }
 
-    std::string package_name =
-        package_substr.empty() ? target_package_name_ : package_substr.to_string();
+    std::string_view package_name = package_substr.empty() ? target_package_name_ : package_substr;
     if (type_name.empty()) {
       return Error("resource name '%s' missing type name", res_entry.resource_name.c_str());
     }
@@ -133,17 +132,14 @@
                     .first;
     }
 
-    auto type = package->second.find(type_name.to_string());
+    auto type = package->second.find(type_name);
     if (type == package->second.end()) {
-      type =
-          package->second
-              .insert(std::make_pair(type_name.to_string(), EntryMap()))
-              .first;
+      type = package->second.insert(std::make_pair(type_name, EntryMap())).first;
     }
 
-    auto entry = type->second.find(entry_name.to_string());
+    auto entry = type->second.find(entry_name);
     if (entry == type->second.end()) {
-      entry = type->second.insert(std::make_pair(entry_name.to_string(), ConfigMap())).first;
+      entry = type->second.insert(std::make_pair(entry_name, ConfigMap())).first;
     }
 
     auto value = entry->second.find(res_entry.configuration);
diff --git a/cmds/idmap2/libidmap2/Idmap.cpp b/cmds/idmap2/libidmap2/Idmap.cpp
index 813dff1..7c0b937 100644
--- a/cmds/idmap2/libidmap2/Idmap.cpp
+++ b/cmds/idmap2/libidmap2/Idmap.cpp
@@ -317,7 +317,7 @@
   }
 
   std::unique_ptr<IdmapData> data(new IdmapData());
-  data->string_pool_data_ = resource_mapping.GetStringPoolData().to_string();
+  data->string_pool_data_ = std::string(resource_mapping.GetStringPoolData());
   uint32_t inline_value_count = 0;
   std::set<std::string> config_set;
   for (const auto& mapping : resource_mapping.GetTargetToOverlayMap()) {
diff --git a/cmds/idmap2/libidmap2/PolicyUtils.cpp b/cmds/idmap2/libidmap2/PolicyUtils.cpp
index 4e3f54d2..76c70ca 100644
--- a/cmds/idmap2/libidmap2/PolicyUtils.cpp
+++ b/cmds/idmap2/libidmap2/PolicyUtils.cpp
@@ -53,7 +53,7 @@
 
   for (const auto& policy : kPolicyStringToFlag) {
     if ((bitmask & policy.second) != 0) {
-      policies.emplace_back(policy.first.to_string());
+      policies.emplace_back(policy.first);
     }
   }