diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 53e5059a..b7a0b55f 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -15,12 +15,22 @@ The repository is organized as follows:
 │   ├── browser_app_entry.tsx   # Entry point for browser app, hosted on GitHub pages.
 │   └── vscode_entry.tsx        # Entry point for VS Code app, output placed under `vscode/assets`.
 ├── vscode/             # The VS Code extension.
-└── rustlib/            # Rust library exporting Wasm functions.
-    └── pkg/            # Output directory for rustlib, installed from package.json via `"./rustlib/pkg"`.
+├── rustlib/            # Rust library exporting Wasm functions.
+│   └── pkg/            # Output directory for rustlib, installed from package.json via `"./rustlib/pkg"`.
+└── tslib/              # TypeScript library shared for common use.
+    ├── react/                  # Common React components.
+    ├── storage/                # Common code for handling storage.
+    └── types/                  # Common TypeScript types.
 ```
 
 ## Python package
 
+#### Building TypeScript packages
+
+```
+$ make tslib
+```
+
 #### Compiling TypeScript files
 
 Node.js v16 is required to compile TypeScript files.
diff --git a/optuna_dashboard/package-lock.json b/optuna_dashboard/package-lock.json
index d888df64..df49f5e1 100644
--- a/optuna_dashboard/package-lock.json
+++ b/optuna_dashboard/package-lock.json
@@ -60,7 +60,10 @@
       "name": "@optuna/types",
       "version": "0.0.1",
       "dev": true,
-      "license": "MIT"
+      "license": "MIT",
+      "devDependencies": {
+        "typescript": "^5.4.5"
+      }
     },
     "node_modules/@ampproject/remapping": {
       "version": "2.3.0",
diff --git a/tslib/react/package-lock.json b/tslib/react/package-lock.json
index 9ae27b21..c2a6befa 100644
--- a/tslib/react/package-lock.json
+++ b/tslib/react/package-lock.json
@@ -43,19 +43,25 @@
       }
     },
     "../storage": {
+      "name": "@optuna/storage",
       "version": "0.0.1",
       "license": "MIT",
       "dependencies": {
         "@sqlite.org/sqlite-wasm": "^3.45.1-build1"
       },
       "devDependencies": {
-        "@optuna/types": "../types/"
+        "@optuna/types": "../types/",
+        "typescript": "^5.4.5"
       }
     },
     "../types": {
+      "name": "@optuna/types",
       "version": "0.0.1",
       "dev": true,
-      "license": "MIT"
+      "license": "MIT",
+      "devDependencies": {
+        "typescript": "^5.4.5"
+      }
     },
     "node_modules/@adobe/css-tools": {
       "version": "4.3.3",
diff --git a/tslib/storage/package-lock.json b/tslib/storage/package-lock.json
index 754056e1..6f6cda06 100644
--- a/tslib/storage/package-lock.json
+++ b/tslib/storage/package-lock.json
@@ -12,7 +12,8 @@
         "@sqlite.org/sqlite-wasm": "^3.45.1-build1"
       },
       "devDependencies": {
-        "@optuna/types": "../types/"
+        "@optuna/types": "../types/",
+        "typescript": "^5.4.5"
       }
     },
     "../entity": {
@@ -25,7 +26,10 @@
       "name": "@optuna/types",
       "version": "0.0.1",
       "dev": true,
-      "license": "MIT"
+      "license": "MIT",
+      "devDependencies": {
+        "typescript": "^5.4.5"
+      }
     },
     "node_modules/@optuna/types": {
       "resolved": "../types",
@@ -38,6 +42,19 @@
       "bin": {
         "sqlite-wasm": "bin/index.js"
       }
+    },
+    "node_modules/typescript": {
+      "version": "5.4.5",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.4.5.tgz",
+      "integrity": "sha512-vcI4UpRgg81oIRUFwR0WSIHKt11nJ7SAVlYNIu+QpqeyXP+gpQJy/Z4+F0aGxSE4MqwjyXvW/TzgkLAx2AGHwQ==",
+      "dev": true,
+      "bin": {
+        "tsc": "bin/tsc",
+        "tsserver": "bin/tsserver"
+      },
+      "engines": {
+        "node": ">=14.17"
+      }
     }
   }
 }
diff --git a/tslib/storage/package.json b/tslib/storage/package.json
index bc2c5707..d02b75ed 100644
--- a/tslib/storage/package.json
+++ b/tslib/storage/package.json
@@ -26,6 +26,7 @@
     "@sqlite.org/sqlite-wasm": "^3.45.1-build1"
   },
   "devDependencies": {
-    "@optuna/types": "../types/"
+    "@optuna/types": "../types/",
+    "typescript": "^5.4.5"
   }
 }
diff --git a/tslib/types/package-lock.json b/tslib/types/package-lock.json
index 77fdf974..8b7fe247 100644
--- a/tslib/types/package-lock.json
+++ b/tslib/types/package-lock.json
@@ -7,7 +7,23 @@
     "": {
       "name": "@optuna/types",
       "version": "0.0.1",
-      "license": "MIT"
+      "license": "MIT",
+      "devDependencies": {
+        "typescript": "^5.4.5"
+      }
+    },
+    "node_modules/typescript": {
+      "version": "5.4.5",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.4.5.tgz",
+      "integrity": "sha512-vcI4UpRgg81oIRUFwR0WSIHKt11nJ7SAVlYNIu+QpqeyXP+gpQJy/Z4+F0aGxSE4MqwjyXvW/TzgkLAx2AGHwQ==",
+      "dev": true,
+      "bin": {
+        "tsc": "bin/tsc",
+        "tsserver": "bin/tsserver"
+      },
+      "engines": {
+        "node": ">=14.17"
+      }
     }
   }
 }
diff --git a/tslib/types/package.json b/tslib/types/package.json
index 2123fd9d..7cdeb1ac 100644
--- a/tslib/types/package.json
+++ b/tslib/types/package.json
@@ -19,5 +19,8 @@
   "bugs": {
     "url": "https://github.com/optuna/optuna-dashboard/issues"
   },
-  "homepage": "https://github.com/optuna/optuna-dashboard#readme"
+  "homepage": "https://github.com/optuna/optuna-dashboard#readme",
+  "devDependencies": {
+    "typescript": "^5.4.5"
+  }
 }