diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..c2658d7
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+node_modules/
diff --git a/.prettierrc.yaml b/.prettierrc.yaml
new file mode 100644
index 0000000..95d290b
--- /dev/null
+++ b/.prettierrc.yaml
@@ -0,0 +1,5 @@
+# https://prettier.io/docs/en/configuration.html
+semi: false
+printWidth: 80
+tabWidth: 4
+singleQuote: true
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..57a645f
--- /dev/null
+++ b/README.md
@@ -0,0 +1,4 @@
+# nodejs-purejs-template
+
+Build a nodejs package in pure javascript,  
+but use [JSDoc](https://www.typescriptlang.org/docs/handbook/jsdoc-supported-types.html) to enable typescript check!
diff --git a/add.mjs b/add.mjs
new file mode 100644
index 0000000..02fcb90
--- /dev/null
+++ b/add.mjs
@@ -0,0 +1,8 @@
+/**
+ * @template {number} T
+ * @param {T} a
+ * @param {T} b
+ */
+export function add(a, b) {
+    return a + b
+}
diff --git a/add.test.mjs b/add.test.mjs
new file mode 100644
index 0000000..97fe994
--- /dev/null
+++ b/add.test.mjs
@@ -0,0 +1,8 @@
+import { test } from 'node:test'
+import { add } from './add.mjs'
+import * as assert from 'node:assert'
+
+test('test add()', async () => {
+    assert.equal(add(1, 1), 2)
+    assert.equal(add(1, -1), 0)
+})
diff --git a/cli.mjs b/cli.mjs
new file mode 100644
index 0000000..8036f99
--- /dev/null
+++ b/cli.mjs
@@ -0,0 +1,60 @@
+import { parseArgs } from 'node:util'
+import process from 'node:process'
+import pkg from './package.json' assert { type: 'json' }
+
+// https://nodejs.org/api/util.html#utilparseargsconfig
+const { values, positionals } = parseArgs({
+    options: {
+        help: {
+            type: 'boolean',
+            multiple: false,
+            short: 'h',
+            default: false,
+        },
+        lhs: {
+            type: 'string',
+            short: 'a',
+            default: '0',
+        },
+        rhs: {
+            type: 'string',
+            short: 'b',
+            default: '0',
+        },
+    },
+    strict: true,
+    allowPositionals: true,
+})
+
+if (positionals.length < 1 || values.help) {
+    help()
+}
+
+const command = positionals[0]
+
+switch (command) {
+    case 'help':
+        help()
+        break
+    case 'add':
+        const { lhs, rhs } = values
+        const sum = Number.parseFloat(lhs) + Number.parseFloat(rhs)
+        console.log('%s + %s = %s', lhs, rhs, sum)
+        break
+    default:
+        process.stderr.write(`Unknown command ${command}\n`)
+        process.exit(1)
+}
+
+function help() {
+    process.stdout.write(`\x1b[32m${pkg.name}\x1b[0m v${pkg.version}
+
+  A nodejs template in pure javascript
+
+  \x1b[1mUsage:\x1b[0m
+
+  cli-name add --lhs [number] --rhs [number]    Get sum of lhs and rhs
+  cli-name help                                 Show this help
+`)
+    process.exit(1)
+}
diff --git a/index.mjs b/index.mjs
new file mode 100644
index 0000000..bc37dd2
--- /dev/null
+++ b/index.mjs
@@ -0,0 +1 @@
+export * from './add.mjs'
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..bd9170c
--- /dev/null
+++ b/package.json
@@ -0,0 +1,25 @@
+{
+    "name": "nodejs-purejs-template",
+    "private": true,
+    "version": "0.1.0",
+    "type": "module",
+    "description": "",
+    "main": "index.mjs",
+    "scripts": {
+        "test": "node --test",
+        "watch": "tsc --watch"
+    },
+    "keywords": [],
+    "author": "",
+    "license": "",
+    "engines": {
+        "node": ">16"
+    },
+    "bin": {
+        "cli-name": "./cli.mjs"
+    },
+    "devDependencies": {
+        "@types/node": "^20.10.6",
+        "typescript": "^5.3.3"
+    }
+}
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..44956c9
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,24 @@
+{
+    // https://www.typescriptlang.org/tsconfig#compilerOptions
+    "compilerOptions": {
+        // Modules
+        "rootDir": "./",
+        "module": "NodeNext",
+        "moduleResolution": "NodeNext",
+        "resolveJsonModule": true,
+
+        // Others
+        "target": "ESNext",
+        "noEmit": true,
+        "skipLibCheck": true,
+
+        // JavaScript Support
+        "allowJs": true,
+        "checkJs": true,
+
+        // Type Checking
+        "strict": false, // (without TS it's hard to express some type)
+        "noFallthroughCasesInSwitch": true,
+        "noPropertyAccessFromIndexSignature": true
+    }
+}