diff --git a/test/component_test.cc b/test/component_test.cc
index da1f701137..5462c18451 100644
--- a/test/component_test.cc
+++ b/test/component_test.cc
@@ -10,7 +10,7 @@
 
 using namespace rime;
 
-class Greeting : public Class<Greeting, const string&> {
+class Greeting : public Class<Greeting, string_view> {
  public:
   virtual string Say() = 0;
   virtual ~Greeting() = default;
@@ -31,10 +31,10 @@ class Hello : public Greeting {
 // customize a hello component with parameters
 class HelloComponent : public Hello::Component {
  public:
-  HelloComponent(const string& word) : word_(word) {}
+  HelloComponent(string_view word) : word_(word) {}
   // define a custom creator to provide an additional argument
-  Hello* Create(const string& name) {
-    return new Hello(make_pair(word_, name));
+  Hello* Create(string_view name) {
+    return new Hello(make_pair(word_, string{name}));
   }
 
  private:
diff --git a/test/config_compiler_test.cc b/test/config_compiler_test.cc
index 18e62945b7..a61b6247aa 100644
--- a/test/config_compiler_test.cc
+++ b/test/config_compiler_test.cc
@@ -7,6 +7,7 @@
 #include <gtest/gtest.h>
 #include <rime/component.h>
 #include <rime/config.h>
+#include <rime/algo/strings.h>
 
 using namespace rime;
 
@@ -35,73 +36,90 @@ TEST_F(RimeConfigCompilerTest, IncludeLocalReference) {
     std::ostringstream oss;
     oss << "include_local_reference/@" << i << "/";
     const auto& prefix(oss.str());
-    EXPECT_TRUE(config_->IsNull(prefix + "__include"));
+    EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__include")));
     string actual;
-    EXPECT_TRUE(config_->GetString(prefix + "terrans/player", &actual));
+    EXPECT_TRUE(config_->GetString(
+        rime::strings::concat(prefix, "terrans/player"), &actual));
     EXPECT_EQ("slayers_boxer", actual);
-    EXPECT_TRUE(config_->GetString(prefix + "protoss/player", &actual));
+    EXPECT_TRUE(config_->GetString(
+        rime::strings::concat(prefix, "protoss/player"), &actual));
     EXPECT_EQ("grrrr", actual);
-    EXPECT_TRUE(config_->GetString(prefix + "zerg/player", &actual));
+    EXPECT_TRUE(config_->GetString(rime::strings::concat(prefix, "zerg/player"),
+                                   &actual));
     EXPECT_EQ("yellow", actual);
   }
 }
 
 TEST_F(RimeConfigCompilerTest, IncludeExternalReference) {
-  const string& prefix = "include_external_reference/";
-  EXPECT_TRUE(config_->IsNull(prefix + "terrans/__include"));
+  string_view prefix = "include_external_reference/";
+  EXPECT_TRUE(
+      config_->IsNull(rime::strings::concat(prefix, "terrans/__include")));
   int mineral = 0;
-  EXPECT_TRUE(config_->GetInt(prefix + "terrans/tank/cost/mineral", &mineral));
+  EXPECT_TRUE(config_->GetInt(
+      rime::strings::concat(prefix, "terrans/tank/cost/mineral"), &mineral));
   EXPECT_EQ(150, mineral);
   int gas = 0;
-  EXPECT_TRUE(config_->GetInt(prefix + "terrans/tank/cost/gas", &gas));
+  EXPECT_TRUE(config_->GetInt(
+      rime::strings::concat(prefix, "terrans/tank/cost/gas"), &gas));
   EXPECT_EQ(100, gas);
-  EXPECT_TRUE(config_->IsNull(prefix + "protoss"));
-  EXPECT_TRUE(config_->IsNull(prefix + "zerg"));
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "protoss")));
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "zerg")));
 }
 
 TEST_F(RimeConfigCompilerTest, IncludeExternalFile) {
-  const string& prefix = "include_external_file/";
-  EXPECT_TRUE(config_->IsNull(prefix + "__include"));
-  EXPECT_TRUE(config_->IsMap(prefix + "terrans"));
-  EXPECT_TRUE(config_->IsMap(prefix + "protoss"));
-  EXPECT_TRUE(config_->IsMap(prefix + "zerg"));
+  string_view prefix = "include_external_file/";
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__include")));
+  EXPECT_TRUE(config_->IsMap(rime::strings::concat(prefix, "terrans")));
+  EXPECT_TRUE(config_->IsMap(rime::strings::concat(prefix, "protoss")));
+  EXPECT_TRUE(config_->IsMap(rime::strings::concat(prefix, "zerg")));
   int number = 0;
-  EXPECT_TRUE(config_->GetInt(prefix + "terrans/supply/produced", &number));
+  EXPECT_TRUE(config_->GetInt(
+      rime::strings::concat(prefix, "terrans/supply/produced"), &number));
   EXPECT_EQ(28, number);
-  EXPECT_TRUE(config_->IsList(prefix + "protoss/air_force"));
+  EXPECT_TRUE(
+      config_->IsList(rime::strings::concat(prefix, "protoss/air_force")));
   string name;
-  EXPECT_TRUE(config_->GetString(prefix + "zerg/queen", &name));
+  EXPECT_TRUE(
+      config_->GetString(rime::strings::concat(prefix, "zerg/queen"), &name));
   EXPECT_EQ("Kerrigan", name);
 }
 
 TEST_F(RimeConfigCompilerTest, PatchReference) {
-  const string& prefix = "patch_reference/";
-  EXPECT_TRUE(config_->IsNull(prefix + "__patch"));
-  EXPECT_EQ(4, config_->GetListSize(prefix + "battlefields"));
+  string_view prefix = "patch_reference/";
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__patch")));
+  EXPECT_EQ(
+      4, config_->GetListSize(rime::strings::concat(prefix, "battlefields")));
   string map;
-  EXPECT_TRUE(config_->GetString(prefix + "battlefields/@3", &map));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "battlefields/@3"), &map));
   EXPECT_EQ("match point", map);
 }
 
 TEST_F(RimeConfigCompilerTest, PatchLiteral) {
-  const string& prefix = "patch_literal/";
-  EXPECT_TRUE(config_->IsNull(prefix + "__patch"));
-  EXPECT_EQ(6, config_->GetListSize(prefix + "zerg/ground_units"));
+  string_view prefix = "patch_literal/";
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__patch")));
+  EXPECT_EQ(6, config_->GetListSize(
+                   rime::strings::concat(prefix, "zerg/ground_units")));
   string unit;
-  EXPECT_TRUE(config_->GetString(prefix + "zerg/ground_units/@5", &unit));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "zerg/ground_units/@5"), &unit));
   EXPECT_EQ("lurker", unit);
   // assert that we patched on a copy of the included node
   EXPECT_EQ(5, config_->GetListSize("/starcraft/zerg/ground_units"));
 }
 
 TEST_F(RimeConfigCompilerTest, PatchList) {
-  const string& prefix = "patch_list/";
-  EXPECT_TRUE(config_->IsNull(prefix + "protoss/__patch"));
-  EXPECT_EQ(8, config_->GetListSize(prefix + "protoss/ground_units"));
+  string_view prefix = "patch_list/";
+  EXPECT_TRUE(
+      config_->IsNull(rime::strings::concat(prefix, "protoss/__patch")));
+  EXPECT_EQ(8, config_->GetListSize(
+                   rime::strings::concat(prefix, "protoss/ground_units")));
   string unit;
-  EXPECT_TRUE(config_->GetString(prefix + "protoss/ground_units/@6", &unit));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "protoss/ground_units/@6"), &unit));
   EXPECT_EQ("dark templar", unit);
-  EXPECT_TRUE(config_->GetString(prefix + "protoss/ground_units/@7", &unit));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "protoss/ground_units/@7"), &unit));
   EXPECT_EQ("dark archon", unit);
   // assert that we patched on a copy of the included node
   EXPECT_EQ(6, config_->GetListSize("/starcraft/protoss/ground_units"));
@@ -113,30 +131,41 @@ class RimeConfigDependencyTest : public RimeConfigCompilerTestBase {
 };
 
 TEST_F(RimeConfigDependencyTest, DependencyChaining) {
-  const string& prefix = "dependency_chaining/";
-  EXPECT_TRUE(config_->IsNull(prefix + "alpha/__include"));
-  EXPECT_TRUE(config_->IsNull(prefix + "beta/__include"));
-  EXPECT_TRUE(config_->IsNull(prefix + "delta/__include"));
+  string_view prefix = "dependency_chaining/";
+  EXPECT_TRUE(
+      config_->IsNull(rime::strings::concat(prefix, "alpha/__include")));
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "beta/__include")));
+  EXPECT_TRUE(
+      config_->IsNull(rime::strings::concat(prefix, "delta/__include")));
   string value;
-  EXPECT_TRUE(config_->GetString(prefix + "alpha", &value));
+  EXPECT_TRUE(
+      config_->GetString(rime::strings::concat(prefix, "alpha"), &value));
   EXPECT_EQ("success", value);
-  EXPECT_TRUE(config_->GetString(prefix + "beta", &value));
+  EXPECT_TRUE(
+      config_->GetString(rime::strings::concat(prefix, "beta"), &value));
   EXPECT_EQ("success", value);
-  EXPECT_TRUE(config_->GetString(prefix + "delta", &value));
+  EXPECT_TRUE(
+      config_->GetString(rime::strings::concat(prefix, "delta"), &value));
   EXPECT_EQ("success", value);
 }
 
 // Unit test for https://github.com/rime/librime/issues/141
 TEST_F(RimeConfigDependencyTest, DependencyPriorities) {
-  const string& prefix = "dependency_priorities/";
-  EXPECT_TRUE(config_->IsNull(prefix + "terrans/__include"));
-  EXPECT_TRUE(config_->IsNull(prefix + "terrans/__patch"));
-  EXPECT_TRUE(config_->IsNull(prefix + "protoss/__include"));
-  EXPECT_TRUE(config_->IsNull(prefix + "protoss/__patch"));
+  string_view prefix = "dependency_priorities/";
+  EXPECT_TRUE(
+      config_->IsNull(rime::strings::concat(prefix, "terrans/__include")));
+  EXPECT_TRUE(
+      config_->IsNull(rime::strings::concat(prefix, "terrans/__patch")));
+  EXPECT_TRUE(
+      config_->IsNull(rime::strings::concat(prefix, "protoss/__include")));
+  EXPECT_TRUE(
+      config_->IsNull(rime::strings::concat(prefix, "protoss/__patch")));
   string player;
-  EXPECT_TRUE(config_->GetString(prefix + "terrans/player", &player));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "terrans/player"), &player));
   EXPECT_EQ("nada", player);
-  EXPECT_TRUE(config_->GetString(prefix + "protoss/player", &player));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "protoss/player"), &player));
   EXPECT_EQ("bisu", player);
 }
 
@@ -148,11 +177,12 @@ class RimeConfigOptionalReferenceTest : public RimeConfigCompilerTestBase {
 };
 
 TEST_F(RimeConfigOptionalReferenceTest, OptionalReference) {
-  const string& prefix = "/";
-  EXPECT_TRUE(config_->IsNull(prefix + "__include"));
-  EXPECT_TRUE(config_->IsNull(prefix + "__patch"));
+  string_view prefix = "/";
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__include")));
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__patch")));
   bool untouched;
-  EXPECT_TRUE(config_->GetBool(prefix + "untouched", &untouched));
+  EXPECT_TRUE(
+      config_->GetBool(rime::strings::concat(prefix, "untouched"), &untouched));
   EXPECT_TRUE(untouched);
 }
 
@@ -162,16 +192,18 @@ class RimeConfigMergeTest : public RimeConfigCompilerTestBase {
 };
 
 TEST_F(RimeConfigMergeTest, AppendWithInclude) {
-  const string& prefix = "append_with_include/";
-  EXPECT_TRUE(config_->IsNull(prefix + "list/__include"));
-  EXPECT_TRUE(config_->IsNull(prefix + "list/__append"));
+  string_view prefix = "append_with_include/";
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "list/__include")));
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "list/__append")));
 
-  EXPECT_TRUE(config_->IsList(prefix + "list"));
-  EXPECT_EQ(6 + 2, config_->GetListSize(prefix + "list"));
+  EXPECT_TRUE(config_->IsList(rime::strings::concat(prefix, "list")));
+  EXPECT_EQ(6 + 2, config_->GetListSize(rime::strings::concat(prefix, "list")));
   string unit;
-  EXPECT_TRUE(config_->GetString(prefix + "list/@6", &unit));
+  EXPECT_TRUE(
+      config_->GetString(rime::strings::concat(prefix, "list/@6"), &unit));
   EXPECT_EQ("dark templar", unit);
-  EXPECT_TRUE(config_->GetString(prefix + "list/@7", &unit));
+  EXPECT_TRUE(
+      config_->GetString(rime::strings::concat(prefix, "list/@7"), &unit));
   EXPECT_EQ("dark archon", unit);
 
   // verify that we append to a copy and the original list is untouched
@@ -179,22 +211,27 @@ TEST_F(RimeConfigMergeTest, AppendWithInclude) {
 }
 
 TEST_F(RimeConfigMergeTest, AppendWithPatch) {
-  const string& prefix = "append_with_patch/";
-  EXPECT_TRUE(config_->IsNull(prefix + "__include"));
-  EXPECT_TRUE(config_->IsNull(prefix + "__patch"));
+  string_view prefix = "append_with_patch/";
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__include")));
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__patch")));
 
   string player;
-  EXPECT_TRUE(config_->GetString(prefix + "terrans/player", &player));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "terrans/player"), &player));
   EXPECT_EQ("slayers_boxer, nada", player);
 
-  EXPECT_EQ(2, config_->GetListSize(prefix + "terrans/air_units"));
+  EXPECT_EQ(2, config_->GetListSize(
+                   rime::strings::concat(prefix, "terrans/air_units")));
   string unit;
-  EXPECT_TRUE(config_->GetString(prefix + "terrans/air_units/@0", &unit));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "terrans/air_units/@0"), &unit));
   EXPECT_EQ("wraith", unit);
-  EXPECT_TRUE(config_->GetString(prefix + "terrans/air_units/@1", &unit));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "terrans/air_units/@1"), &unit));
   EXPECT_EQ("battlecruiser", unit);
 
-  EXPECT_EQ(6 + 2, config_->GetListSize(prefix + "protoss/ground_units"));
+  EXPECT_EQ(6 + 2, config_->GetListSize(
+                       rime::strings::concat(prefix, "protoss/ground_units")));
 
   // verify that we append to a copy and the original list is untouched
   EXPECT_TRUE(config_->GetString("/starcraft/terrans/player", &player));
@@ -204,35 +241,50 @@ TEST_F(RimeConfigMergeTest, AppendWithPatch) {
 }
 
 TEST_F(RimeConfigMergeTest, MergeTree) {
-  const string& prefix = "merge_tree/";
-  EXPECT_TRUE(config_->IsNull(prefix + "__include"));
+  string_view prefix = "merge_tree/";
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__include")));
 
   string player;
-  EXPECT_TRUE(config_->GetString(prefix + "terrans/player", &player));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "terrans/player"), &player));
   EXPECT_EQ("slayers_boxer", player);
-  EXPECT_TRUE(config_->IsNull(prefix + "terrans/air_units"));
-  EXPECT_TRUE(config_->IsList(prefix + "terrans/ground_units"));
-  EXPECT_EQ(5 + 2, config_->GetListSize(prefix + "terrans/ground_units"));
+  EXPECT_TRUE(
+      config_->IsNull(rime::strings::concat(prefix, "terrans/air_units")));
+  EXPECT_TRUE(
+      config_->IsList(rime::strings::concat(prefix, "terrans/ground_units")));
+  EXPECT_EQ(5 + 2, config_->GetListSize(
+                       rime::strings::concat(prefix, "terrans/ground_units")));
   string unit;
-  EXPECT_TRUE(config_->GetString(prefix + "terrans/ground_units/@5", &unit));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "terrans/ground_units/@5"), &unit));
   EXPECT_EQ("medic", unit);
-  EXPECT_TRUE(config_->GetString(prefix + "terrans/ground_units/@6", &unit));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "terrans/ground_units/@6"), &unit));
   EXPECT_EQ("goliath", unit);
 
-  EXPECT_TRUE(config_->GetString(prefix + "protoss/player", &player));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "protoss/player"), &player));
   EXPECT_EQ("grrrr", player);
-  EXPECT_TRUE(config_->IsNull(prefix + "protoss/ground_units/__append"));
-  EXPECT_TRUE(config_->IsList(prefix + "protoss/ground_units"));
-  EXPECT_EQ(6 + 2, config_->GetListSize(prefix + "protoss/ground_units"));
-  EXPECT_TRUE(config_->GetString(prefix + "protoss/ground_units/@6", &unit));
+  EXPECT_TRUE(config_->IsNull(
+      rime::strings::concat(prefix, "protoss/ground_units/__append")));
+  EXPECT_TRUE(
+      config_->IsList(rime::strings::concat(prefix, "protoss/ground_units")));
+  EXPECT_EQ(6 + 2, config_->GetListSize(
+                       rime::strings::concat(prefix, "protoss/ground_units")));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "protoss/ground_units/@6"), &unit));
   EXPECT_EQ("dark templar", unit);
-  EXPECT_TRUE(config_->GetString(prefix + "protoss/ground_units/@7", &unit));
+  EXPECT_TRUE(config_->GetString(
+      rime::strings::concat(prefix, "protoss/ground_units/@7"), &unit));
   EXPECT_EQ("dark archon", unit);
 
-  EXPECT_TRUE(config_->GetString(prefix + "zerg/player", &player));
+  EXPECT_TRUE(config_->GetString(rime::strings::concat(prefix, "zerg/player"),
+                                 &player));
   EXPECT_EQ("yellow", player);
-  EXPECT_TRUE(config_->IsList(prefix + "zerg/ground_units"));
-  EXPECT_EQ(0, config_->GetListSize(prefix + "zerg/ground_units"));
+  EXPECT_TRUE(
+      config_->IsList(rime::strings::concat(prefix, "zerg/ground_units")));
+  EXPECT_EQ(0, config_->GetListSize(
+                   rime::strings::concat(prefix, "zerg/ground_units")));
 
   // verify that we merge to a copy and the original list is untouched
   EXPECT_TRUE(config_->IsNull("/starcraft/terrans/ground_units"));
@@ -248,19 +300,21 @@ class RimeConfigCircularDependencyTest : public RimeConfigCompilerTestBase {
 };
 
 TEST_F(RimeConfigMergeTest, CreateListWithInplacePatch) {
-  const string& prefix = "create_list_with_inplace_patch/";
-  EXPECT_TRUE(config_->IsList(prefix + "all_ground_units"));
-  EXPECT_EQ(16, config_->GetListSize(prefix + "all_ground_units"));
+  string_view prefix = "create_list_with_inplace_patch/";
+  EXPECT_TRUE(
+      config_->IsList(rime::strings::concat(prefix, "all_ground_units")));
+  EXPECT_EQ(16, config_->GetListSize(
+                    rime::strings::concat(prefix, "all_ground_units")));
 }
 
 TEST_F(RimeConfigCircularDependencyTest, BestEffortResolution) {
-  const string& prefix = "test/";
-  EXPECT_TRUE(config_->IsNull(prefix + "__patch"));
-  EXPECT_TRUE(config_->IsNull(prefix + "work/__include"));
+  string_view prefix = "test/";
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "__patch")));
+  EXPECT_TRUE(config_->IsNull(rime::strings::concat(prefix, "work/__include")));
   string home;
-  EXPECT_TRUE(config_->GetString(prefix + "home", &home));
+  EXPECT_TRUE(config_->GetString(rime::strings::concat(prefix, "home"), &home));
   EXPECT_EQ("naive", home);
   string work;
-  EXPECT_TRUE(config_->GetString(prefix + "work", &work));
+  EXPECT_TRUE(config_->GetString(rime::strings::concat(prefix, "work"), &work));
   EXPECT_EQ("excited", work);
 }
diff --git a/tools/rime_console.cc b/tools/rime_console.cc
index 6907351933..07092b0162 100644
--- a/tools/rime_console.cc
+++ b/tools/rime_console.cc
@@ -68,7 +68,7 @@ class RimeConsole {
     }
   }
 
-  void ProcessLine(const string& line) {
+  void ProcessLine(string_view line) {
     KeySequence keys;
     if (!keys.Parse(line)) {
       LOG(ERROR) << "error parsing input: '" << line << "'";
diff --git a/tools/rime_deployer.cc b/tools/rime_deployer.cc
index 8360ac5b90..e030ddcfb9 100644
--- a/tools/rime_deployer.cc
+++ b/tools/rime_deployer.cc
@@ -46,7 +46,7 @@ int add_schema(int count, char* schemas[]) {
   return 0;
 }
 
-int set_active_schema(const string& schema_id) {
+int set_active_schema(string_view schema_id) {
   Config config;
   if (!config.LoadFromFile(path{"user.yaml"})) {
     LOG(INFO) << "creating new file 'user.yaml'.";
diff --git a/tools/rime_patch.cc b/tools/rime_patch.cc
index 652a1c3216..c12a03e7ed 100644
--- a/tools/rime_patch.cc
+++ b/tools/rime_patch.cc
@@ -17,9 +17,7 @@
 
 using namespace rime;
 
-int apply_patch(const string& config_id,
-                const string& key,
-                const string& yaml) {
+int apply_patch(string_view config_id, string_view key, string_view yaml) {
   RimeApi* rime = rime_get_api();
   RimeModule* module = rime->find_module("levers");
   if (!module) {
@@ -31,12 +29,12 @@ int apply_patch(const string& config_id,
   int ret = 1;
 
   RimeConfig value = {0};  // should be zero-initialized
-  if (rime->config_load_string(&value, yaml.c_str())) {
+  if (rime->config_load_string(&value, yaml.data())) {
     RimeCustomSettings* settings =
-        levers->custom_settings_init(config_id.c_str(), "rime_patch");
+        levers->custom_settings_init(config_id.data(), "rime_patch");
     levers->load_settings(settings);
 
-    if (levers->customize_item(settings, key.c_str(), &value)) {
+    if (levers->customize_item(settings, key.data(), &value)) {
       levers->save_settings(settings);
       std::cerr << "patch applied." << std::endl;
       ret = 0;