diff --git a/.github/workflows/node.js.yml b/.github/workflows/node.js.yml
index 7d887db..ce8cb9c 100644
--- a/.github/workflows/node.js.yml
+++ b/.github/workflows/node.js.yml
@@ -1,6 +1,3 @@
-# This workflow will do a clean installation of node dependencies, cache/restore them, build the source code and run tests across different versions of node
-# For more information see: https://help.github.com/actions/language-and-framework-guides/using-nodejs-with-github-actions
-
 name: Node.js CI
 
 on:
@@ -15,7 +12,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [18.x, 20.x, 22.x]
+        node-version: [22.x, 24.x, 25.x]
 
     steps:
       - uses: actions/checkout@v4
diff --git a/.npmignore b/.npmignore
index cbc1a6e..a22489e 100644
--- a/.npmignore
+++ b/.npmignore
@@ -1,6 +1,5 @@
 test/
 coverage/
-jest.config.js
 .gitattributes
 package-lock.json
 .github/
diff --git a/README.md b/README.md
index 798552b..7af111d 100644
--- a/README.md
+++ b/README.md
@@ -2,20 +2,12 @@
 
 Join two iterables (e.g. arrays) of objects by a common (user-defined) key, similarly to how SQL JOIN, LEFT JOIN and FULL JOIN work.
 
-[![code style: prettier](https://img.shields.io/badge/code_style-prettier-ff69b4.svg?style=flat-square)](https://github.com/prettier/prettier)
-
 ## Installation
 
 ```sh
 npm install array-join
 ```
 
-or
-
-```sh
-yarn add array-join
-```
-
 ## Usage
 
 `join(leftCollection, rightCollection, getLeftKey, getRightKey, getResultItem)`
@@ -141,14 +133,19 @@ will include non-matching items from both collections
   {
     left: { id: 3, name: 'Alice' },
     right: undefined
-  }
+  },
   {
     left: undefined,
-    right:{ personId: 4, address: { city: 'London', country: 'UK' } }
+    right: { personId: 4, address: { city: 'London', country: 'UK' } }
   }
 ]
 ```
 
+## Breaking changes in version 4
+
+- ESM-only package (CommonJS is no longer supported)
+- Minimum Node.js version is 22
+
 ## Breaking changes in version 3
 
 - Rewritten on TypeScript (which ensures typings to be correct)
diff --git a/jest.config.js b/jest.config.js
deleted file mode 100644
index ca2aa6f..0000000
--- a/jest.config.js
+++ /dev/null
@@ -1,13 +0,0 @@
-module.exports = {
-  testEnvironment: "node",
-  preset: "ts-jest",
-  collectCoverageFrom: ["src/**/*.ts"],
-  coverageThreshold: {
-    global: {
-      branches: 100,
-      functions: 100,
-      lines: 100,
-      statements: 100,
-    },
-  },
-};
diff --git a/package-lock.json b/package-lock.json
index 5d73281..a31d786 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -9,19 +9,19 @@
       "version": "3.2.1",
       "license": "MIT",
       "devDependencies": {
-        "@types/node": "^22.18.10",
-        "prettier": "^3.6.2",
-        "tsx": "^4.20.6",
+        "@types/node": "^24.12.0",
+        "prettier": "^3.8.1",
+        "tsx": "^4.21.0",
         "typescript": "^5.9.3"
       },
       "engines": {
-        "node": ">=18.0.0"
+        "node": ">=22.0.0"
       }
     },
     "node_modules/@esbuild/aix-ppc64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/aix-ppc64/-/aix-ppc64-0.25.11.tgz",
-      "integrity": "sha512-Xt1dOL13m8u0WE8iplx9Ibbm+hFAO0GsU2P34UNoDGvZYkY8ifSiy6Zuc1lYxfG7svWE2fzqCUmFp5HCn51gJg==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/aix-ppc64/-/aix-ppc64-0.27.3.tgz",
+      "integrity": "sha512-9fJMTNFTWZMh5qwrBItuziu834eOCUcEqymSH7pY+zoMVEZg3gcPuBNxH1EvfVYe9h0x/Ptw8KBzv7qxb7l8dg==",
       "cpu": [
         "ppc64"
       ],
@@ -36,9 +36,9 @@
       }
     },
     "node_modules/@esbuild/android-arm": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/android-arm/-/android-arm-0.25.11.tgz",
-      "integrity": "sha512-uoa7dU+Dt3HYsethkJ1k6Z9YdcHjTrSb5NUy66ZfZaSV8hEYGD5ZHbEMXnqLFlbBflLsl89Zke7CAdDJ4JI+Gg==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/android-arm/-/android-arm-0.27.3.tgz",
+      "integrity": "sha512-i5D1hPY7GIQmXlXhs2w8AWHhenb00+GxjxRncS2ZM7YNVGNfaMxgzSGuO8o8SJzRc/oZwU2bcScvVERk03QhzA==",
       "cpu": [
         "arm"
       ],
@@ -53,9 +53,9 @@
       }
     },
     "node_modules/@esbuild/android-arm64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/android-arm64/-/android-arm64-0.25.11.tgz",
-      "integrity": "sha512-9slpyFBc4FPPz48+f6jyiXOx/Y4v34TUeDDXJpZqAWQn/08lKGeD8aDp9TMn9jDz2CiEuHwfhRmGBvpnd/PWIQ==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/android-arm64/-/android-arm64-0.27.3.tgz",
+      "integrity": "sha512-YdghPYUmj/FX2SYKJ0OZxf+iaKgMsKHVPF1MAq/P8WirnSpCStzKJFjOjzsW0QQ7oIAiccHdcqjbHmJxRb/dmg==",
       "cpu": [
         "arm64"
       ],
@@ -70,9 +70,9 @@
       }
     },
     "node_modules/@esbuild/android-x64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/android-x64/-/android-x64-0.25.11.tgz",
-      "integrity": "sha512-Sgiab4xBjPU1QoPEIqS3Xx+R2lezu0LKIEcYe6pftr56PqPygbB7+szVnzoShbx64MUupqoE0KyRlN7gezbl8g==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/android-x64/-/android-x64-0.27.3.tgz",
+      "integrity": "sha512-IN/0BNTkHtk8lkOM8JWAYFg4ORxBkZQf9zXiEOfERX/CzxW3Vg1ewAhU7QSWQpVIzTW+b8Xy+lGzdYXV6UZObQ==",
       "cpu": [
         "x64"
       ],
@@ -87,9 +87,9 @@
       }
     },
     "node_modules/@esbuild/darwin-arm64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/darwin-arm64/-/darwin-arm64-0.25.11.tgz",
-      "integrity": "sha512-VekY0PBCukppoQrycFxUqkCojnTQhdec0vevUL/EDOCnXd9LKWqD/bHwMPzigIJXPhC59Vd1WFIL57SKs2mg4w==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/darwin-arm64/-/darwin-arm64-0.27.3.tgz",
+      "integrity": "sha512-Re491k7ByTVRy0t3EKWajdLIr0gz2kKKfzafkth4Q8A5n1xTHrkqZgLLjFEHVD+AXdUGgQMq+Godfq45mGpCKg==",
       "cpu": [
         "arm64"
       ],
@@ -104,9 +104,9 @@
       }
     },
     "node_modules/@esbuild/darwin-x64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/darwin-x64/-/darwin-x64-0.25.11.tgz",
-      "integrity": "sha512-+hfp3yfBalNEpTGp9loYgbknjR695HkqtY3d3/JjSRUyPg/xd6q+mQqIb5qdywnDxRZykIHs3axEqU6l1+oWEQ==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/darwin-x64/-/darwin-x64-0.27.3.tgz",
+      "integrity": "sha512-vHk/hA7/1AckjGzRqi6wbo+jaShzRowYip6rt6q7VYEDX4LEy1pZfDpdxCBnGtl+A5zq8iXDcyuxwtv3hNtHFg==",
       "cpu": [
         "x64"
       ],
@@ -121,9 +121,9 @@
       }
     },
     "node_modules/@esbuild/freebsd-arm64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/freebsd-arm64/-/freebsd-arm64-0.25.11.tgz",
-      "integrity": "sha512-CmKjrnayyTJF2eVuO//uSjl/K3KsMIeYeyN7FyDBjsR3lnSJHaXlVoAK8DZa7lXWChbuOk7NjAc7ygAwrnPBhA==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/freebsd-arm64/-/freebsd-arm64-0.27.3.tgz",
+      "integrity": "sha512-ipTYM2fjt3kQAYOvo6vcxJx3nBYAzPjgTCk7QEgZG8AUO3ydUhvelmhrbOheMnGOlaSFUoHXB6un+A7q4ygY9w==",
       "cpu": [
         "arm64"
       ],
@@ -138,9 +138,9 @@
       }
     },
     "node_modules/@esbuild/freebsd-x64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/freebsd-x64/-/freebsd-x64-0.25.11.tgz",
-      "integrity": "sha512-Dyq+5oscTJvMaYPvW3x3FLpi2+gSZTCE/1ffdwuM6G1ARang/mb3jvjxs0mw6n3Lsw84ocfo9CrNMqc5lTfGOw==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/freebsd-x64/-/freebsd-x64-0.27.3.tgz",
+      "integrity": "sha512-dDk0X87T7mI6U3K9VjWtHOXqwAMJBNN2r7bejDsc+j03SEjtD9HrOl8gVFByeM0aJksoUuUVU9TBaZa2rgj0oA==",
       "cpu": [
         "x64"
       ],
@@ -155,9 +155,9 @@
       }
     },
     "node_modules/@esbuild/linux-arm": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/linux-arm/-/linux-arm-0.25.11.tgz",
-      "integrity": "sha512-TBMv6B4kCfrGJ8cUPo7vd6NECZH/8hPpBHHlYI3qzoYFvWu2AdTvZNuU/7hsbKWqu/COU7NIK12dHAAqBLLXgw==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/linux-arm/-/linux-arm-0.27.3.tgz",
+      "integrity": "sha512-s6nPv2QkSupJwLYyfS+gwdirm0ukyTFNl3KTgZEAiJDd+iHZcbTPPcWCcRYH+WlNbwChgH2QkE9NSlNrMT8Gfw==",
       "cpu": [
         "arm"
       ],
@@ -172,9 +172,9 @@
       }
     },
     "node_modules/@esbuild/linux-arm64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/linux-arm64/-/linux-arm64-0.25.11.tgz",
-      "integrity": "sha512-Qr8AzcplUhGvdyUF08A1kHU3Vr2O88xxP0Tm8GcdVOUm25XYcMPp2YqSVHbLuXzYQMf9Bh/iKx7YPqECs6ffLA==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/linux-arm64/-/linux-arm64-0.27.3.tgz",
+      "integrity": "sha512-sZOuFz/xWnZ4KH3YfFrKCf1WyPZHakVzTiqji3WDc0BCl2kBwiJLCXpzLzUBLgmp4veFZdvN5ChW4Eq/8Fc2Fg==",
       "cpu": [
         "arm64"
       ],
@@ -189,9 +189,9 @@
       }
     },
     "node_modules/@esbuild/linux-ia32": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/linux-ia32/-/linux-ia32-0.25.11.tgz",
-      "integrity": "sha512-TmnJg8BMGPehs5JKrCLqyWTVAvielc615jbkOirATQvWWB1NMXY77oLMzsUjRLa0+ngecEmDGqt5jiDC6bfvOw==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/linux-ia32/-/linux-ia32-0.27.3.tgz",
+      "integrity": "sha512-yGlQYjdxtLdh0a3jHjuwOrxQjOZYD/C9PfdbgJJF3TIZWnm/tMd/RcNiLngiu4iwcBAOezdnSLAwQDPqTmtTYg==",
       "cpu": [
         "ia32"
       ],
@@ -206,9 +206,9 @@
       }
     },
     "node_modules/@esbuild/linux-loong64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/linux-loong64/-/linux-loong64-0.25.11.tgz",
-      "integrity": "sha512-DIGXL2+gvDaXlaq8xruNXUJdT5tF+SBbJQKbWy/0J7OhU8gOHOzKmGIlfTTl6nHaCOoipxQbuJi7O++ldrxgMw==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/linux-loong64/-/linux-loong64-0.27.3.tgz",
+      "integrity": "sha512-WO60Sn8ly3gtzhyjATDgieJNet/KqsDlX5nRC5Y3oTFcS1l0KWba+SEa9Ja1GfDqSF1z6hif/SkpQJbL63cgOA==",
       "cpu": [
         "loong64"
       ],
@@ -223,9 +223,9 @@
       }
     },
     "node_modules/@esbuild/linux-mips64el": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/linux-mips64el/-/linux-mips64el-0.25.11.tgz",
-      "integrity": "sha512-Osx1nALUJu4pU43o9OyjSCXokFkFbyzjXb6VhGIJZQ5JZi8ylCQ9/LFagolPsHtgw6himDSyb5ETSfmp4rpiKQ==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/linux-mips64el/-/linux-mips64el-0.27.3.tgz",
+      "integrity": "sha512-APsymYA6sGcZ4pD6k+UxbDjOFSvPWyZhjaiPyl/f79xKxwTnrn5QUnXR5prvetuaSMsb4jgeHewIDCIWljrSxw==",
       "cpu": [
         "mips64el"
       ],
@@ -240,9 +240,9 @@
       }
     },
     "node_modules/@esbuild/linux-ppc64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/linux-ppc64/-/linux-ppc64-0.25.11.tgz",
-      "integrity": "sha512-nbLFgsQQEsBa8XSgSTSlrnBSrpoWh7ioFDUmwo158gIm5NNP+17IYmNWzaIzWmgCxq56vfr34xGkOcZ7jX6CPw==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/linux-ppc64/-/linux-ppc64-0.27.3.tgz",
+      "integrity": "sha512-eizBnTeBefojtDb9nSh4vvVQ3V9Qf9Df01PfawPcRzJH4gFSgrObw+LveUyDoKU3kxi5+9RJTCWlj4FjYXVPEA==",
       "cpu": [
         "ppc64"
       ],
@@ -257,9 +257,9 @@
       }
     },
     "node_modules/@esbuild/linux-riscv64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/linux-riscv64/-/linux-riscv64-0.25.11.tgz",
-      "integrity": "sha512-HfyAmqZi9uBAbgKYP1yGuI7tSREXwIb438q0nqvlpxAOs3XnZ8RsisRfmVsgV486NdjD7Mw2UrFSw51lzUk1ww==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/linux-riscv64/-/linux-riscv64-0.27.3.tgz",
+      "integrity": "sha512-3Emwh0r5wmfm3ssTWRQSyVhbOHvqegUDRd0WhmXKX2mkHJe1SFCMJhagUleMq+Uci34wLSipf8Lagt4LlpRFWQ==",
       "cpu": [
         "riscv64"
       ],
@@ -274,9 +274,9 @@
       }
     },
     "node_modules/@esbuild/linux-s390x": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/linux-s390x/-/linux-s390x-0.25.11.tgz",
-      "integrity": "sha512-HjLqVgSSYnVXRisyfmzsH6mXqyvj0SA7pG5g+9W7ESgwA70AXYNpfKBqh1KbTxmQVaYxpzA/SvlB9oclGPbApw==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/linux-s390x/-/linux-s390x-0.27.3.tgz",
+      "integrity": "sha512-pBHUx9LzXWBc7MFIEEL0yD/ZVtNgLytvx60gES28GcWMqil8ElCYR4kvbV2BDqsHOvVDRrOxGySBM9Fcv744hw==",
       "cpu": [
         "s390x"
       ],
@@ -291,9 +291,9 @@
       }
     },
     "node_modules/@esbuild/linux-x64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/linux-x64/-/linux-x64-0.25.11.tgz",
-      "integrity": "sha512-HSFAT4+WYjIhrHxKBwGmOOSpphjYkcswF449j6EjsjbinTZbp8PJtjsVK1XFJStdzXdy/jaddAep2FGY+wyFAQ==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/linux-x64/-/linux-x64-0.27.3.tgz",
+      "integrity": "sha512-Czi8yzXUWIQYAtL/2y6vogER8pvcsOsk5cpwL4Gk5nJqH5UZiVByIY8Eorm5R13gq+DQKYg0+JyQoytLQas4dA==",
       "cpu": [
         "x64"
       ],
@@ -308,9 +308,9 @@
       }
     },
     "node_modules/@esbuild/netbsd-arm64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/netbsd-arm64/-/netbsd-arm64-0.25.11.tgz",
-      "integrity": "sha512-hr9Oxj1Fa4r04dNpWr3P8QKVVsjQhqrMSUzZzf+LZcYjZNqhA3IAfPQdEh1FLVUJSiu6sgAwp3OmwBfbFgG2Xg==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/netbsd-arm64/-/netbsd-arm64-0.27.3.tgz",
+      "integrity": "sha512-sDpk0RgmTCR/5HguIZa9n9u+HVKf40fbEUt+iTzSnCaGvY9kFP0YKBWZtJaraonFnqef5SlJ8/TiPAxzyS+UoA==",
       "cpu": [
         "arm64"
       ],
@@ -325,9 +325,9 @@
       }
     },
     "node_modules/@esbuild/netbsd-x64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/netbsd-x64/-/netbsd-x64-0.25.11.tgz",
-      "integrity": "sha512-u7tKA+qbzBydyj0vgpu+5h5AeudxOAGncb8N6C9Kh1N4n7wU1Xw1JDApsRjpShRpXRQlJLb9wY28ELpwdPcZ7A==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/netbsd-x64/-/netbsd-x64-0.27.3.tgz",
+      "integrity": "sha512-P14lFKJl/DdaE00LItAukUdZO5iqNH7+PjoBm+fLQjtxfcfFE20Xf5CrLsmZdq5LFFZzb5JMZ9grUwvtVYzjiA==",
       "cpu": [
         "x64"
       ],
@@ -342,9 +342,9 @@
       }
     },
     "node_modules/@esbuild/openbsd-arm64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/openbsd-arm64/-/openbsd-arm64-0.25.11.tgz",
-      "integrity": "sha512-Qq6YHhayieor3DxFOoYM1q0q1uMFYb7cSpLD2qzDSvK1NAvqFi8Xgivv0cFC6J+hWVw2teCYltyy9/m/14ryHg==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/openbsd-arm64/-/openbsd-arm64-0.27.3.tgz",
+      "integrity": "sha512-AIcMP77AvirGbRl/UZFTq5hjXK+2wC7qFRGoHSDrZ5v5b8DK/GYpXW3CPRL53NkvDqb9D+alBiC/dV0Fb7eJcw==",
       "cpu": [
         "arm64"
       ],
@@ -359,9 +359,9 @@
       }
     },
     "node_modules/@esbuild/openbsd-x64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/openbsd-x64/-/openbsd-x64-0.25.11.tgz",
-      "integrity": "sha512-CN+7c++kkbrckTOz5hrehxWN7uIhFFlmS/hqziSFVWpAzpWrQoAG4chH+nN3Be+Kzv/uuo7zhX716x3Sn2Jduw==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/openbsd-x64/-/openbsd-x64-0.27.3.tgz",
+      "integrity": "sha512-DnW2sRrBzA+YnE70LKqnM3P+z8vehfJWHXECbwBmH/CU51z6FiqTQTHFenPlHmo3a8UgpLyH3PT+87OViOh1AQ==",
       "cpu": [
         "x64"
       ],
@@ -376,9 +376,9 @@
       }
     },
     "node_modules/@esbuild/openharmony-arm64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/openharmony-arm64/-/openharmony-arm64-0.25.11.tgz",
-      "integrity": "sha512-rOREuNIQgaiR+9QuNkbkxubbp8MSO9rONmwP5nKncnWJ9v5jQ4JxFnLu4zDSRPf3x4u+2VN4pM4RdyIzDty/wQ==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/openharmony-arm64/-/openharmony-arm64-0.27.3.tgz",
+      "integrity": "sha512-NinAEgr/etERPTsZJ7aEZQvvg/A6IsZG/LgZy+81wON2huV7SrK3e63dU0XhyZP4RKGyTm7aOgmQk0bGp0fy2g==",
       "cpu": [
         "arm64"
       ],
@@ -393,9 +393,9 @@
       }
     },
     "node_modules/@esbuild/sunos-x64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/sunos-x64/-/sunos-x64-0.25.11.tgz",
-      "integrity": "sha512-nq2xdYaWxyg9DcIyXkZhcYulC6pQ2FuCgem3LI92IwMgIZ69KHeY8T4Y88pcwoLIjbed8n36CyKoYRDygNSGhA==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/sunos-x64/-/sunos-x64-0.27.3.tgz",
+      "integrity": "sha512-PanZ+nEz+eWoBJ8/f8HKxTTD172SKwdXebZ0ndd953gt1HRBbhMsaNqjTyYLGLPdoWHy4zLU7bDVJztF5f3BHA==",
       "cpu": [
         "x64"
       ],
@@ -410,9 +410,9 @@
       }
     },
     "node_modules/@esbuild/win32-arm64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/win32-arm64/-/win32-arm64-0.25.11.tgz",
-      "integrity": "sha512-3XxECOWJq1qMZ3MN8srCJ/QfoLpL+VaxD/WfNRm1O3B4+AZ/BnLVgFbUV3eiRYDMXetciH16dwPbbHqwe1uU0Q==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/win32-arm64/-/win32-arm64-0.27.3.tgz",
+      "integrity": "sha512-B2t59lWWYrbRDw/tjiWOuzSsFh1Y/E95ofKz7rIVYSQkUYBjfSgf6oeYPNWHToFRr2zx52JKApIcAS/D5TUBnA==",
       "cpu": [
         "arm64"
       ],
@@ -427,9 +427,9 @@
       }
     },
     "node_modules/@esbuild/win32-ia32": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/win32-ia32/-/win32-ia32-0.25.11.tgz",
-      "integrity": "sha512-3ukss6gb9XZ8TlRyJlgLn17ecsK4NSQTmdIXRASVsiS2sQ6zPPZklNJT5GR5tE/MUarymmy8kCEf5xPCNCqVOA==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/win32-ia32/-/win32-ia32-0.27.3.tgz",
+      "integrity": "sha512-QLKSFeXNS8+tHW7tZpMtjlNb7HKau0QDpwm49u0vUp9y1WOF+PEzkU84y9GqYaAVW8aH8f3GcBck26jh54cX4Q==",
       "cpu": [
         "ia32"
       ],
@@ -444,9 +444,9 @@
       }
     },
     "node_modules/@esbuild/win32-x64": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/@esbuild/win32-x64/-/win32-x64-0.25.11.tgz",
-      "integrity": "sha512-D7Hpz6A2L4hzsRpPaCYkQnGOotdUpDzSGRIv9I+1ITdHROSFUWW95ZPZWQmGka1Fg7W3zFJowyn9WGwMJ0+KPA==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/@esbuild/win32-x64/-/win32-x64-0.27.3.tgz",
+      "integrity": "sha512-4uJGhsxuptu3OcpVAzli+/gWusVGwZZHTlS63hh++ehExkVT8SgiEf7/uC/PclrPPkLhZqGgCTjd0VWLo6xMqA==",
       "cpu": [
         "x64"
       ],
@@ -461,19 +461,19 @@
       }
     },
     "node_modules/@types/node": {
-      "version": "22.18.10",
-      "resolved": "https://registry.npmjs.org/@types/node/-/node-22.18.10.tgz",
-      "integrity": "sha512-anNG/V/Efn/YZY4pRzbACnKxNKoBng2VTFydVu8RRs5hQjikP8CQfaeAV59VFSCzKNp90mXiVXW2QzV56rwMrg==",
+      "version": "24.12.0",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-24.12.0.tgz",
+      "integrity": "sha512-GYDxsZi3ChgmckRT9HPU0WEhKLP08ev/Yfcq2AstjrDASOYCSXeyjDsHg4v5t4jOj7cyDX3vmprafKlWIG9MXQ==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "undici-types": "~6.21.0"
+        "undici-types": "~7.16.0"
       }
     },
     "node_modules/esbuild": {
-      "version": "0.25.11",
-      "resolved": "https://registry.npmjs.org/esbuild/-/esbuild-0.25.11.tgz",
-      "integrity": "sha512-KohQwyzrKTQmhXDW1PjCv3Tyspn9n5GcY2RTDqeORIdIJY8yKIF7sTSopFmn/wpMPW4rdPXI0UE5LJLuq3bx0Q==",
+      "version": "0.27.3",
+      "resolved": "https://registry.npmjs.org/esbuild/-/esbuild-0.27.3.tgz",
+      "integrity": "sha512-8VwMnyGCONIs6cWue2IdpHxHnAjzxnw2Zr7MkVxB2vjmQ2ivqGFb4LEG3SMnv0Gb2F/G/2yA8zUaiL1gywDCCg==",
       "dev": true,
       "hasInstallScript": true,
       "license": "MIT",
@@ -484,32 +484,32 @@
         "node": ">=18"
       },
       "optionalDependencies": {
-        "@esbuild/aix-ppc64": "0.25.11",
-        "@esbuild/android-arm": "0.25.11",
-        "@esbuild/android-arm64": "0.25.11",
-        "@esbuild/android-x64": "0.25.11",
-        "@esbuild/darwin-arm64": "0.25.11",
-        "@esbuild/darwin-x64": "0.25.11",
-        "@esbuild/freebsd-arm64": "0.25.11",
-        "@esbuild/freebsd-x64": "0.25.11",
-        "@esbuild/linux-arm": "0.25.11",
-        "@esbuild/linux-arm64": "0.25.11",
-        "@esbuild/linux-ia32": "0.25.11",
-        "@esbuild/linux-loong64": "0.25.11",
-        "@esbuild/linux-mips64el": "0.25.11",
-        "@esbuild/linux-ppc64": "0.25.11",
-        "@esbuild/linux-riscv64": "0.25.11",
-        "@esbuild/linux-s390x": "0.25.11",
-        "@esbuild/linux-x64": "0.25.11",
-        "@esbuild/netbsd-arm64": "0.25.11",
-        "@esbuild/netbsd-x64": "0.25.11",
-        "@esbuild/openbsd-arm64": "0.25.11",
-        "@esbuild/openbsd-x64": "0.25.11",
-        "@esbuild/openharmony-arm64": "0.25.11",
-        "@esbuild/sunos-x64": "0.25.11",
-        "@esbuild/win32-arm64": "0.25.11",
-        "@esbuild/win32-ia32": "0.25.11",
-        "@esbuild/win32-x64": "0.25.11"
+        "@esbuild/aix-ppc64": "0.27.3",
+        "@esbuild/android-arm": "0.27.3",
+        "@esbuild/android-arm64": "0.27.3",
+        "@esbuild/android-x64": "0.27.3",
+        "@esbuild/darwin-arm64": "0.27.3",
+        "@esbuild/darwin-x64": "0.27.3",
+        "@esbuild/freebsd-arm64": "0.27.3",
+        "@esbuild/freebsd-x64": "0.27.3",
+        "@esbuild/linux-arm": "0.27.3",
+        "@esbuild/linux-arm64": "0.27.3",
+        "@esbuild/linux-ia32": "0.27.3",
+        "@esbuild/linux-loong64": "0.27.3",
+        "@esbuild/linux-mips64el": "0.27.3",
+        "@esbuild/linux-ppc64": "0.27.3",
+        "@esbuild/linux-riscv64": "0.27.3",
+        "@esbuild/linux-s390x": "0.27.3",
+        "@esbuild/linux-x64": "0.27.3",
+        "@esbuild/netbsd-arm64": "0.27.3",
+        "@esbuild/netbsd-x64": "0.27.3",
+        "@esbuild/openbsd-arm64": "0.27.3",
+        "@esbuild/openbsd-x64": "0.27.3",
+        "@esbuild/openharmony-arm64": "0.27.3",
+        "@esbuild/sunos-x64": "0.27.3",
+        "@esbuild/win32-arm64": "0.27.3",
+        "@esbuild/win32-ia32": "0.27.3",
+        "@esbuild/win32-x64": "0.27.3"
       }
     },
     "node_modules/fsevents": {
@@ -528,9 +528,9 @@
       }
     },
     "node_modules/get-tsconfig": {
-      "version": "4.12.0",
-      "resolved": "https://registry.npmjs.org/get-tsconfig/-/get-tsconfig-4.12.0.tgz",
-      "integrity": "sha512-LScr2aNr2FbjAjZh2C6X6BxRx1/x+aTDExct/xyq2XKbYOiG5c0aK7pMsSuyc0brz3ibr/lbQiHD9jzt4lccJw==",
+      "version": "4.13.6",
+      "resolved": "https://registry.npmjs.org/get-tsconfig/-/get-tsconfig-4.13.6.tgz",
+      "integrity": "sha512-shZT/QMiSHc/YBLxxOkMtgSid5HFoauqCE3/exfsEcwg1WkeqjG+V40yBbBrsD+jW2HDXcs28xOfcbm2jI8Ddw==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -541,9 +541,9 @@
       }
     },
     "node_modules/prettier": {
-      "version": "3.6.2",
-      "resolved": "https://registry.npmjs.org/prettier/-/prettier-3.6.2.tgz",
-      "integrity": "sha512-I7AIg5boAr5R0FFtJ6rCfD+LFsWHp81dolrFD8S79U9tb8Az2nGrJncnMSnys+bpQJfRUzqs9hnA81OAA3hCuQ==",
+      "version": "3.8.1",
+      "resolved": "https://registry.npmjs.org/prettier/-/prettier-3.8.1.tgz",
+      "integrity": "sha512-UOnG6LftzbdaHZcKoPFtOcCKztrQ57WkHDeRD9t/PTQtmT0NHSeWWepj6pS0z/N7+08BHFDQVUrfmfMRcZwbMg==",
       "dev": true,
       "license": "MIT",
       "bin": {
@@ -567,13 +567,13 @@
       }
     },
     "node_modules/tsx": {
-      "version": "4.20.6",
-      "resolved": "https://registry.npmjs.org/tsx/-/tsx-4.20.6.tgz",
-      "integrity": "sha512-ytQKuwgmrrkDTFP4LjR0ToE2nqgy886GpvRSpU0JAnrdBYppuY5rLkRUYPU1yCryb24SsKBTL/hlDQAEFVwtZg==",
+      "version": "4.21.0",
+      "resolved": "https://registry.npmjs.org/tsx/-/tsx-4.21.0.tgz",
+      "integrity": "sha512-5C1sg4USs1lfG0GFb2RLXsdpXqBSEhAaA/0kPL01wxzpMqLILNxIxIOKiILz+cdg/pLnOUxFYOR5yhHU666wbw==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "esbuild": "~0.25.0",
+        "esbuild": "~0.27.0",
         "get-tsconfig": "^4.7.5"
       },
       "bin": {
@@ -601,9 +601,9 @@
       }
     },
     "node_modules/undici-types": {
-      "version": "6.21.0",
-      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-6.21.0.tgz",
-      "integrity": "sha512-iwDZqg0QAGrg9Rav5H4n0M64c3mkR59cJ6wQp+7C4nI0gsmExaedaYLNO44eT4AtBBwjbTiGPMlt2Md0T9H9JQ==",
+      "version": "7.16.0",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-7.16.0.tgz",
+      "integrity": "sha512-Zz+aZWSj8LE6zoxD+xrjh4VfkIG8Ya6LvYkZqtUQGJPZjYl53ypCaUwWqo7eI0x66KBGeRo+mlBEkMSeSZ38Nw==",
       "dev": true,
       "license": "MIT"
     }
diff --git a/package.json b/package.json
index c223857..64b58db 100644
--- a/package.json
+++ b/package.json
@@ -6,8 +6,14 @@
     "type": "git",
     "url": "git+https://github.com/iredchuk/array-join"
   },
+  "type": "module",
   "main": "./dist/index.js",
-  "exports": "./dist/index.js",
+  "exports": {
+    ".": {
+      "types": "./dist/index.d.ts",
+      "default": "./dist/index.js"
+    }
+  },
   "types": "./dist/index.d.ts",
   "author": {
     "name": "Igor Redchuk",
@@ -24,7 +30,7 @@
   ],
   "license": "MIT",
   "engines": {
-    "node": ">=18.0.0"
+    "node": ">=22.0.0"
   },
   "scripts": {
     "test": "tsx --test --experimental-test-coverage test/*.test.ts",
@@ -33,9 +39,9 @@
     "prepare": "npm test && npm run build"
   },
   "devDependencies": {
-    "@types/node": "^22.18.10",
-    "prettier": "^3.6.2",
-    "tsx": "^4.20.6",
+    "@types/node": "^24.12.0",
+    "prettier": "^3.8.1",
+    "tsx": "^4.21.0",
     "typescript": "^5.9.3"
   }
 }
diff --git a/src/index.ts b/src/index.ts
index 00d8b72..0e996b7 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -3,18 +3,15 @@ const createMap = <TItem, TKey>(
   getKey: (a: TItem) => TKey
 ): Map<TKey, TItem[]> => {
   const map = new Map<TKey, TItem[]>();
-
   for (const item of collection) {
-    const value = getKey(item);
-    if (map.has(value)) {
-      const items = map.get(value);
-      items!.push(item);
-      map.set(value, items!);
+    const key = getKey(item);
+    const existing = map.get(key);
+    if (existing) {
+      existing.push(item);
     } else {
-      map.set(value, [item]);
+      map.set(key, [item]);
     }
   }
-
   return map;
 };
 
@@ -39,30 +36,27 @@ const joinIntern = <TLeft, TRight, TKey, TResult>(
 
   const result: TResult[] = [];
 
-  for (const key of leftMap.keys()) {
-    if (rightMap.has(key)) {
-      const leftItems = leftMap.get(key);
-      const rightItems = rightMap.get(key);
-      leftItems!.forEach((leftItem) =>
-        rightItems!.forEach((rightItem) =>
-          result.push(getResultItem(leftItem, rightItem))
-        )
-      );
+  for (const [key, leftItems] of leftMap) {
+    const rightItems = rightMap.get(key);
+    if (rightItems) {
+      for (const leftItem of leftItems) {
+        for (const rightItem of rightItems) {
+          result.push(getResultItem(leftItem, rightItem));
+        }
+      }
     } else if (alwaysIncludeLeftItems) {
-      const leftItems = leftMap.get(key);
-      leftItems!.forEach((leftItem) =>
-        result.push(getResultItem(leftItem, undefined))
-      );
+      for (const leftItem of leftItems) {
+        result.push(getResultItem(leftItem, undefined));
+      }
     }
   }
 
   if (alwaysIncludeRightItems) {
-    for (const key of rightMap.keys()) {
+    for (const [key, rightItems] of rightMap) {
       if (!leftMap.has(key)) {
-        const rightItems = rightMap.get(key);
-        rightItems!.forEach((rightItem) =>
-          result.push(getResultItem(undefined, rightItem))
-        );
+        for (const rightItem of rightItems) {
+          result.push(getResultItem(undefined, rightItem));
+        }
       }
     }
   }
diff --git a/test/index.test.ts b/test/index.test.ts
index df9a1c2..5ae5607 100644
--- a/test/index.test.ts
+++ b/test/index.test.ts
@@ -1,6 +1,6 @@
-import assert from "node:assert/strict";
+import * as assert from "node:assert/strict";
 import { describe, test } from "node:test";
-import { fullJoin, join, leftJoin } from "../src/index";
+import { fullJoin, join, leftJoin } from "../src/index.js";
 
 interface LeftItem {
   id: number;
diff --git a/tsconfig.json b/tsconfig.json
index 0432a15..2dbfb57 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,18 +1,13 @@
 {
   "compilerOptions": {
-    "target": "ES2020",
-    "module": "CommonJS",
-    "moduleResolution": "node",
-    "esModuleInterop": true,
+    "target": "ES2022",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "verbatimModuleSyntax": true,
     "noEmit": true,
     "strict": true,
-    "allowSyntheticDefaultImports": true,
-    "forceConsistentCasingInFileNames": true,
-    "isolatedModules": true,
     "resolveJsonModule": true,
-    "noEmitOnError": true,
     "noFallthroughCasesInSwitch": true,
-    "noImplicitAny": true,
     "noImplicitReturns": true,
     "noImplicitOverride": true,
     "noPropertyAccessFromIndexSignature": true,