diff --git a/README.md b/README.md
index fac9fde..1818f31 100644
--- a/README.md
+++ b/README.md
@@ -70,6 +70,12 @@ interface Person {
     const author = importer.getAllItems<Person>(config.owner);
 
 ```
+# Samples
+
+Sample integration with `xlsx-import` are placed in [./samples](./samples) directory, Currently available:
+
+* [NodeJS sample](./samples/nodejs/README.md) of **importing an invoice** - it is pure JS example which runs on nodejs.
+
 # The configuration:
 
 ## `worksheet` 
diff --git a/samples/nodejs/README.md b/samples/nodejs/README.md
new file mode 100644
index 0000000..dee2b5e
--- /dev/null
+++ b/samples/nodejs/README.md
@@ -0,0 +1,37 @@
+# Hello
+
+This is an example how to use `xlsx-import` in a pure node javascript.
+
+## Usage
+
+```bash
+# install
+npm install
+
+# execute
+node index.js 
+
+
+# or execute and save into file
+node index.js > result.json
+```
+
+## What happened?
+
+1. Read spreadsheet file [Invoice.xlsx](invoice.xlsx)
+2. Following config import invoice data
+3. Map, return and display data _(should be same as [result.json](./result.json))_.
+
+## What is worth to see here?
+
+1. Study importer configs: [`invoiceConfig.js`](configs/invoiceConfig.js)
+2. Usage package in [`importer.js`](importer.js)
+
+## What later:
+
+1. Study documentation: [docs](./../../README.md)
+2. Start using `xlsx-import` in your project
+3. Ask a lot, report bugs and request for help: https://github.com/Siemienik/xlsx-import/issues
+4. [Sponsor `xlsx-import` project](https://github.com/sponsors/Siemienik) 
+
+
diff --git a/samples/nodejs/configs/invoiceConfig.js b/samples/nodejs/configs/invoiceConfig.js
new file mode 100644
index 0000000..1e155c2
--- /dev/null
+++ b/samples/nodejs/configs/invoiceConfig.js
@@ -0,0 +1,45 @@
+const getInvoiceConfig = () => ({
+    seller: {
+        worksheet: 'Invoice',
+        type: 'object',
+        fields: [
+            {row: 2, col: 1, key: 'name'},
+            {row: 4, col: 2, key: 'taxIdNumber'},
+            {row: 3, col: 1, key: 'address'},
+            {row: 9, col: 4, key: 'accountNo'},
+        ]
+    },
+
+    buyer: {
+        worksheet: 'Invoice',
+        type: 'object',
+        fields: [
+            {row: 2, col: 5, key: 'name'},
+            {row: 4, col: 6, key: 'taxIdNumber'},
+            {row: 3, col: 5, key: 'address'},
+        ]
+    },
+
+    misc: {
+        worksheet: 'Invoice',
+        type: 'object',
+        fields: [
+            {row: 6, col: 5, key: 'date', mapper: (v)=>new Date(v)}, //todo mapper
+            {row: 7, col: 5, key: 'dueDate', mapper: (v)=>new Date(v)}, //todo mapper
+        ]
+    },
+
+    items: {
+        worksheet: 'Invoice',
+        type: 'list',
+        rowOffset: 13,
+        columns: [
+            { index: 2, key: 'item'},
+            { index: 4, key: 'unitPrice', mapper: (v)=>Number(v)},
+            { index: 5, key: 'quantity', mapper: (v)=>Number(v)},
+            { index: 6, key: 'price', mapper: (v)=>Number(v)},
+        ]
+    }
+});
+
+module.exports = {getInvoiceConfig};
\ No newline at end of file
diff --git a/samples/nodejs/importer.js b/samples/nodejs/importer.js
new file mode 100644
index 0000000..369d677
--- /dev/null
+++ b/samples/nodejs/importer.js
@@ -0,0 +1,28 @@
+const ImporterFactory = require('xlsx-import/lib/ImporterFactory').default;
+const { getInvoiceConfig } = require('./configs/invoiceConfig');
+
+const factory = new ImporterFactory();
+
+const importInvoice = async (invoicePath) => {
+    const config = getInvoiceConfig();
+
+    const importer = await factory.From(invoicePath);
+
+    const {date, dueDate} = importer.GetAllItems(config.misc)[0];
+    const seller = importer.GetAllItems(config.seller)[0];
+    const buyer = importer.GetAllItems(config.buyer)[0];
+    const items = importer.GetAllItems(config.items);
+
+    const total = items.reduce((p, c) => p + c.price, 0);
+
+    return {
+        date,
+        dueDate,
+        seller,
+        buyer,
+        items,
+        total
+    }
+}
+
+module.exports = {importInvoice};
diff --git a/samples/nodejs/index.js b/samples/nodejs/index.js
new file mode 100644
index 0000000..30809c6
--- /dev/null
+++ b/samples/nodejs/index.js
@@ -0,0 +1,5 @@
+const {importInvoice} = require("./importer");
+
+importInvoice( __dirname+"/invoice.xlsx").then((invoice)=>{
+    console.log(invoice);
+})
\ No newline at end of file
diff --git a/samples/nodejs/invoice.xlsx b/samples/nodejs/invoice.xlsx
new file mode 100644
index 0000000..c1dcdea
Binary files /dev/null and b/samples/nodejs/invoice.xlsx differ
diff --git a/samples/nodejs/package-lock.json b/samples/nodejs/package-lock.json
new file mode 100644
index 0000000..280d119
--- /dev/null
+++ b/samples/nodejs/package-lock.json
@@ -0,0 +1,688 @@
+{
+  "name": "@xlsx-import/samples-nodejs",
+  "version": "0.0.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "@fast-csv/format": {
+      "version": "4.3.1",
+      "resolved": "https://registry.npmjs.org/@fast-csv/format/-/format-4.3.1.tgz",
+      "integrity": "sha512-Ap6KSt0iJlzrivZU4grQzDGGOQ+vN5kvUeOHLF1BE7nWri1auiodgS3SCffvLe1Zvu79tACe1tw3dyBADk1NsA==",
+      "requires": {
+        "lodash.escaperegexp": "^4.1.2",
+        "lodash.isboolean": "^3.0.3",
+        "lodash.isequal": "^4.5.0",
+        "lodash.isfunction": "^3.0.9",
+        "lodash.isnil": "^4.0.0"
+      }
+    },
+    "@fast-csv/parse": {
+      "version": "4.3.2",
+      "resolved": "https://registry.npmjs.org/@fast-csv/parse/-/parse-4.3.2.tgz",
+      "integrity": "sha512-smFKL1E00zy6SB+MIRL4kJq4ba4Is9mHEf+1kdMH7iLInrKszADyJFGicoRfiFTtAvm+661LJMWjyQHrmx6WeA==",
+      "requires": {
+        "lodash.escaperegexp": "^4.1.2",
+        "lodash.groupby": "^4.6.0",
+        "lodash.isfunction": "^3.0.9",
+        "lodash.isnil": "^4.0.0",
+        "lodash.isundefined": "^3.0.1",
+        "lodash.uniq": "^4.5.0"
+      }
+    },
+    "@types/node": {
+      "version": "14.11.5",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-14.11.5.tgz",
+      "integrity": "sha512-jVFzDV6NTbrLMxm4xDSIW/gKnk8rQLF9wAzLWIOg+5nU6ACrIMndeBdXci0FGtqJbP9tQvm6V39eshc96TO2wQ=="
+    },
+    "archiver": {
+      "version": "4.0.2",
+      "resolved": "https://registry.npmjs.org/archiver/-/archiver-4.0.2.tgz",
+      "integrity": "sha512-B9IZjlGwaxF33UN4oPbfBkyA4V1SxNLeIhR1qY8sRXSsbdUkEHrrOvwlYFPx+8uQeCe9M+FG6KgO+imDmQ79CQ==",
+      "requires": {
+        "archiver-utils": "^2.1.0",
+        "async": "^3.2.0",
+        "buffer-crc32": "^0.2.1",
+        "glob": "^7.1.6",
+        "readable-stream": "^3.6.0",
+        "tar-stream": "^2.1.2",
+        "zip-stream": "^3.0.1"
+      }
+    },
+    "archiver-utils": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/archiver-utils/-/archiver-utils-2.1.0.tgz",
+      "integrity": "sha512-bEL/yUb/fNNiNTuUz979Z0Yg5L+LzLxGJz8x79lYmR54fmTIb6ob/hNQgkQnIUDWIFjZVQwl9Xs356I6BAMHfw==",
+      "requires": {
+        "glob": "^7.1.4",
+        "graceful-fs": "^4.2.0",
+        "lazystream": "^1.0.0",
+        "lodash.defaults": "^4.2.0",
+        "lodash.difference": "^4.5.0",
+        "lodash.flatten": "^4.4.0",
+        "lodash.isplainobject": "^4.0.6",
+        "lodash.union": "^4.6.0",
+        "normalize-path": "^3.0.0",
+        "readable-stream": "^2.0.0"
+      },
+      "dependencies": {
+        "readable-stream": {
+          "version": "2.3.7",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.7.tgz",
+          "integrity": "sha512-Ebho8K4jIbHAxnuxi7o42OrZgF/ZTNcsZj6nRKyUmkhLFq8CHItp/fy6hQZuZmP/n3yZ9VBUbp4zz/mX8hmYPw==",
+          "requires": {
+            "core-util-is": "~1.0.0",
+            "inherits": "~2.0.3",
+            "isarray": "~1.0.0",
+            "process-nextick-args": "~2.0.0",
+            "safe-buffer": "~5.1.1",
+            "string_decoder": "~1.1.1",
+            "util-deprecate": "~1.0.1"
+          }
+        }
+      }
+    },
+    "async": {
+      "version": "3.2.0",
+      "resolved": "https://registry.npmjs.org/async/-/async-3.2.0.tgz",
+      "integrity": "sha512-TR2mEZFVOj2pLStYxLht7TyfuRzaydfpxr3k9RpHIzMgw7A64dzsdqCxH1WJyQdoe8T10nDXd9wnEigmiuHIZw=="
+    },
+    "balanced-match": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.0.tgz",
+      "integrity": "sha1-ibTRmasr7kneFk6gK4nORi1xt2c="
+    },
+    "base64-js": {
+      "version": "1.3.1",
+      "resolved": "https://registry.npmjs.org/base64-js/-/base64-js-1.3.1.tgz",
+      "integrity": "sha512-mLQ4i2QO1ytvGWFWmcngKO//JXAQueZvwEKtjgQFM4jIK0kU+ytMfplL8j+n5mspOfjHwoAg+9yhb7BwAHm36g=="
+    },
+    "big-integer": {
+      "version": "1.6.48",
+      "resolved": "https://registry.npmjs.org/big-integer/-/big-integer-1.6.48.tgz",
+      "integrity": "sha512-j51egjPa7/i+RdiRuJbPdJ2FIUYYPhvYLjzoYbcMMm62ooO6F94fETG4MTs46zPAF9Brs04OajboA/qTGuz78w=="
+    },
+    "binary": {
+      "version": "0.3.0",
+      "resolved": "https://registry.npmjs.org/binary/-/binary-0.3.0.tgz",
+      "integrity": "sha1-n2BVO8XOjDOG87VTz/R0Yq3sqnk=",
+      "requires": {
+        "buffers": "~0.1.1",
+        "chainsaw": "~0.1.0"
+      }
+    },
+    "bl": {
+      "version": "4.0.3",
+      "resolved": "https://registry.npmjs.org/bl/-/bl-4.0.3.tgz",
+      "integrity": "sha512-fs4G6/Hu4/EE+F75J8DuN/0IpQqNjAdC7aEQv7Qt8MHGUH7Ckv2MwTEEeN9QehD0pfIDkMI1bkHYkKy7xHyKIg==",
+      "requires": {
+        "buffer": "^5.5.0",
+        "inherits": "^2.0.4",
+        "readable-stream": "^3.4.0"
+      }
+    },
+    "bluebird": {
+      "version": "3.4.7",
+      "resolved": "https://registry.npmjs.org/bluebird/-/bluebird-3.4.7.tgz",
+      "integrity": "sha1-9y12C+Cbf3bQjtj66Ysomo0F+rM="
+    },
+    "brace-expansion": {
+      "version": "1.1.11",
+      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
+      "integrity": "sha512-iCuPHDFgrHX7H2vEI/5xpz07zSHB00TpugqhmYtVmMO6518mCuRMoOYFldEBl0g187ufozdaHgWKcYFb61qGiA==",
+      "requires": {
+        "balanced-match": "^1.0.0",
+        "concat-map": "0.0.1"
+      }
+    },
+    "buffer": {
+      "version": "5.6.0",
+      "resolved": "https://registry.npmjs.org/buffer/-/buffer-5.6.0.tgz",
+      "integrity": "sha512-/gDYp/UtU0eA1ys8bOs9J6a+E/KWIY+DZ+Q2WESNUA0jFRsJOc0SNUO6xJ5SGA1xueg3NL65W6s+NY5l9cunuw==",
+      "requires": {
+        "base64-js": "^1.0.2",
+        "ieee754": "^1.1.4"
+      }
+    },
+    "buffer-crc32": {
+      "version": "0.2.13",
+      "resolved": "https://registry.npmjs.org/buffer-crc32/-/buffer-crc32-0.2.13.tgz",
+      "integrity": "sha1-DTM+PwDqxQqhRUq9MO+MKl2ackI="
+    },
+    "buffer-indexof-polyfill": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/buffer-indexof-polyfill/-/buffer-indexof-polyfill-1.0.2.tgz",
+      "integrity": "sha512-I7wzHwA3t1/lwXQh+A5PbNvJxgfo5r3xulgpYDB5zckTu/Z9oUK9biouBKQUjEqzaz3HnAT6TYoovmE+GqSf7A=="
+    },
+    "buffers": {
+      "version": "0.1.1",
+      "resolved": "https://registry.npmjs.org/buffers/-/buffers-0.1.1.tgz",
+      "integrity": "sha1-skV5w77U1tOWru5tmorn9Ugqt7s="
+    },
+    "chainsaw": {
+      "version": "0.1.0",
+      "resolved": "https://registry.npmjs.org/chainsaw/-/chainsaw-0.1.0.tgz",
+      "integrity": "sha1-XqtQsor+WAdNDVgpE4iCi15fvJg=",
+      "requires": {
+        "traverse": ">=0.3.0 <0.4"
+      }
+    },
+    "compress-commons": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/compress-commons/-/compress-commons-3.0.0.tgz",
+      "integrity": "sha512-FyDqr8TKX5/X0qo+aVfaZ+PVmNJHJeckFBlq8jZGSJOgnynhfifoyl24qaqdUdDIBe0EVTHByN6NAkqYvE/2Xg==",
+      "requires": {
+        "buffer-crc32": "^0.2.13",
+        "crc32-stream": "^3.0.1",
+        "normalize-path": "^3.0.0",
+        "readable-stream": "^2.3.7"
+      },
+      "dependencies": {
+        "readable-stream": {
+          "version": "2.3.7",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.7.tgz",
+          "integrity": "sha512-Ebho8K4jIbHAxnuxi7o42OrZgF/ZTNcsZj6nRKyUmkhLFq8CHItp/fy6hQZuZmP/n3yZ9VBUbp4zz/mX8hmYPw==",
+          "requires": {
+            "core-util-is": "~1.0.0",
+            "inherits": "~2.0.3",
+            "isarray": "~1.0.0",
+            "process-nextick-args": "~2.0.0",
+            "safe-buffer": "~5.1.1",
+            "string_decoder": "~1.1.1",
+            "util-deprecate": "~1.0.1"
+          }
+        }
+      }
+    },
+    "concat-map": {
+      "version": "0.0.1",
+      "resolved": "https://registry.npmjs.org/concat-map/-/concat-map-0.0.1.tgz",
+      "integrity": "sha1-2Klr13/Wjfd5OnMDajug1UBdR3s="
+    },
+    "core-util-is": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/core-util-is/-/core-util-is-1.0.2.tgz",
+      "integrity": "sha1-tf1UIgqivFq1eqtxQMlAdUUDwac="
+    },
+    "crc": {
+      "version": "3.8.0",
+      "resolved": "https://registry.npmjs.org/crc/-/crc-3.8.0.tgz",
+      "integrity": "sha512-iX3mfgcTMIq3ZKLIsVFAbv7+Mc10kxabAGQb8HvjA1o3T1PIYprbakQ65d3I+2HGHt6nSKkM9PYjgoJO2KcFBQ==",
+      "requires": {
+        "buffer": "^5.1.0"
+      }
+    },
+    "crc32-stream": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/crc32-stream/-/crc32-stream-3.0.1.tgz",
+      "integrity": "sha512-mctvpXlbzsvK+6z8kJwSJ5crm7yBwrQMTybJzMw1O4lLGJqjlDCXY2Zw7KheiA6XBEcBmfLx1D88mjRGVJtY9w==",
+      "requires": {
+        "crc": "^3.4.4",
+        "readable-stream": "^3.4.0"
+      }
+    },
+    "dayjs": {
+      "version": "1.9.1",
+      "resolved": "https://registry.npmjs.org/dayjs/-/dayjs-1.9.1.tgz",
+      "integrity": "sha512-01NCTBg8cuMJG1OQc6PR7T66+AFYiPwgDvdJmvJBn29NGzIG+DIFxPLNjHzwz3cpFIvG+NcwIjP9hSaPVoOaDg=="
+    },
+    "duplexer2": {
+      "version": "0.1.4",
+      "resolved": "https://registry.npmjs.org/duplexer2/-/duplexer2-0.1.4.tgz",
+      "integrity": "sha1-ixLauHjA1p4+eJEFFmKjL8a93ME=",
+      "requires": {
+        "readable-stream": "^2.0.2"
+      },
+      "dependencies": {
+        "readable-stream": {
+          "version": "2.3.7",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.7.tgz",
+          "integrity": "sha512-Ebho8K4jIbHAxnuxi7o42OrZgF/ZTNcsZj6nRKyUmkhLFq8CHItp/fy6hQZuZmP/n3yZ9VBUbp4zz/mX8hmYPw==",
+          "requires": {
+            "core-util-is": "~1.0.0",
+            "inherits": "~2.0.3",
+            "isarray": "~1.0.0",
+            "process-nextick-args": "~2.0.0",
+            "safe-buffer": "~5.1.1",
+            "string_decoder": "~1.1.1",
+            "util-deprecate": "~1.0.1"
+          }
+        }
+      }
+    },
+    "end-of-stream": {
+      "version": "1.4.4",
+      "resolved": "https://registry.npmjs.org/end-of-stream/-/end-of-stream-1.4.4.tgz",
+      "integrity": "sha512-+uw1inIHVPQoaVuHzRyXd21icM+cnt4CzD5rW+NC1wjOUSTOs+Te7FOv7AhN7vS9x/oIyhLP5PR1H+phQAHu5Q==",
+      "requires": {
+        "once": "^1.4.0"
+      }
+    },
+    "exceljs": {
+      "version": "4.1.1",
+      "resolved": "https://registry.npmjs.org/exceljs/-/exceljs-4.1.1.tgz",
+      "integrity": "sha512-DWdCXInpk69qY+Xf7VLiQJulg5B6VpcbSidsgLl92Pu0v9/sh83VLkAsaWbw58Ap8gfhH2sVoGyxHMqRKnyAPA==",
+      "requires": {
+        "archiver": "^4.0.1",
+        "dayjs": "^1.8.26",
+        "fast-csv": "^4.1.2",
+        "jszip": "^3.4.0",
+        "readable-stream": "^3.6.0",
+        "saxes": "^5.0.1",
+        "tmp": "^0.2.0",
+        "unzipper": "^0.10.11",
+        "uuid": "^7.0.3"
+      }
+    },
+    "fast-csv": {
+      "version": "4.3.2",
+      "resolved": "https://registry.npmjs.org/fast-csv/-/fast-csv-4.3.2.tgz",
+      "integrity": "sha512-tmvVMsliprsl7P1z++XuhfGZPTz/h2sTLhs5PYVhtOSsu7t0T2q1TdWq/CORQsD9Cc2oPiTchpf7gACLXArNYQ==",
+      "requires": {
+        "@fast-csv/format": "4.3.1",
+        "@fast-csv/parse": "4.3.2",
+        "@types/node": "^14.0.1"
+      }
+    },
+    "fs-constants": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/fs-constants/-/fs-constants-1.0.0.tgz",
+      "integrity": "sha512-y6OAwoSIf7FyjMIv94u+b5rdheZEjzR63GTyZJm5qh4Bi+2YgwLCcI/fPFZkL5PSixOt6ZNKm+w+Hfp/Bciwow=="
+    },
+    "fs.realpath": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/fs.realpath/-/fs.realpath-1.0.0.tgz",
+      "integrity": "sha1-FQStJSMVjKpA20onh8sBQRmU6k8="
+    },
+    "fstream": {
+      "version": "1.0.12",
+      "resolved": "https://registry.npmjs.org/fstream/-/fstream-1.0.12.tgz",
+      "integrity": "sha512-WvJ193OHa0GHPEL+AycEJgxvBEwyfRkN1vhjca23OaPVMCaLCXTd5qAu82AjTcgP1UJmytkOKb63Ypde7raDIg==",
+      "requires": {
+        "graceful-fs": "^4.1.2",
+        "inherits": "~2.0.0",
+        "mkdirp": ">=0.5 0",
+        "rimraf": "2"
+      },
+      "dependencies": {
+        "rimraf": {
+          "version": "2.7.1",
+          "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-2.7.1.tgz",
+          "integrity": "sha512-uWjbaKIK3T1OSVptzX7Nl6PvQ3qAGtKEtVRjRuazjfL3Bx5eI409VZSqgND+4UNnmzLVdPj9FqFJNPqBZFve4w==",
+          "requires": {
+            "glob": "^7.1.3"
+          }
+        }
+      }
+    },
+    "glob": {
+      "version": "7.1.6",
+      "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.6.tgz",
+      "integrity": "sha512-LwaxwyZ72Lk7vZINtNNrywX0ZuLyStrdDtabefZKAY5ZGJhVtgdznluResxNmPitE0SAO+O26sWTHeKSI2wMBA==",
+      "requires": {
+        "fs.realpath": "^1.0.0",
+        "inflight": "^1.0.4",
+        "inherits": "2",
+        "minimatch": "^3.0.4",
+        "once": "^1.3.0",
+        "path-is-absolute": "^1.0.0"
+      }
+    },
+    "graceful-fs": {
+      "version": "4.2.4",
+      "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.4.tgz",
+      "integrity": "sha512-WjKPNJF79dtJAVniUlGGWHYGz2jWxT6VhN/4m1NdkbZ2nOsEF+cI1Edgql5zCRhs/VsQYRvrXctxktVXZUkixw=="
+    },
+    "ieee754": {
+      "version": "1.1.13",
+      "resolved": "https://registry.npmjs.org/ieee754/-/ieee754-1.1.13.tgz",
+      "integrity": "sha512-4vf7I2LYV/HaWerSo3XmlMkp5eZ83i+/CDluXi/IGTs/O1sejBNhTtnxzmRZfvOUqj7lZjqHkeTvpgSFDlWZTg=="
+    },
+    "immediate": {
+      "version": "3.0.6",
+      "resolved": "https://registry.npmjs.org/immediate/-/immediate-3.0.6.tgz",
+      "integrity": "sha1-nbHb0Pr43m++D13V5Wu2BigN5ps="
+    },
+    "inflight": {
+      "version": "1.0.6",
+      "resolved": "https://registry.npmjs.org/inflight/-/inflight-1.0.6.tgz",
+      "integrity": "sha1-Sb1jMdfQLQwJvJEKEHW6gWW1bfk=",
+      "requires": {
+        "once": "^1.3.0",
+        "wrappy": "1"
+      }
+    },
+    "inherits": {
+      "version": "2.0.4",
+      "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
+      "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ=="
+    },
+    "isarray": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/isarray/-/isarray-1.0.0.tgz",
+      "integrity": "sha1-u5NdSFgsuhaMBoNJV6VKPgcSTxE="
+    },
+    "jszip": {
+      "version": "3.5.0",
+      "resolved": "https://registry.npmjs.org/jszip/-/jszip-3.5.0.tgz",
+      "integrity": "sha512-WRtu7TPCmYePR1nazfrtuF216cIVon/3GWOvHS9QR5bIwSbnxtdpma6un3jyGGNhHsKCSzn5Ypk+EkDRvTGiFA==",
+      "requires": {
+        "lie": "~3.3.0",
+        "pako": "~1.0.2",
+        "readable-stream": "~2.3.6",
+        "set-immediate-shim": "~1.0.1"
+      },
+      "dependencies": {
+        "readable-stream": {
+          "version": "2.3.7",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.7.tgz",
+          "integrity": "sha512-Ebho8K4jIbHAxnuxi7o42OrZgF/ZTNcsZj6nRKyUmkhLFq8CHItp/fy6hQZuZmP/n3yZ9VBUbp4zz/mX8hmYPw==",
+          "requires": {
+            "core-util-is": "~1.0.0",
+            "inherits": "~2.0.3",
+            "isarray": "~1.0.0",
+            "process-nextick-args": "~2.0.0",
+            "safe-buffer": "~5.1.1",
+            "string_decoder": "~1.1.1",
+            "util-deprecate": "~1.0.1"
+          }
+        }
+      }
+    },
+    "lazystream": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/lazystream/-/lazystream-1.0.0.tgz",
+      "integrity": "sha1-9plf4PggOS9hOWvolGJAe7dxaOQ=",
+      "requires": {
+        "readable-stream": "^2.0.5"
+      },
+      "dependencies": {
+        "readable-stream": {
+          "version": "2.3.7",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.7.tgz",
+          "integrity": "sha512-Ebho8K4jIbHAxnuxi7o42OrZgF/ZTNcsZj6nRKyUmkhLFq8CHItp/fy6hQZuZmP/n3yZ9VBUbp4zz/mX8hmYPw==",
+          "requires": {
+            "core-util-is": "~1.0.0",
+            "inherits": "~2.0.3",
+            "isarray": "~1.0.0",
+            "process-nextick-args": "~2.0.0",
+            "safe-buffer": "~5.1.1",
+            "string_decoder": "~1.1.1",
+            "util-deprecate": "~1.0.1"
+          }
+        }
+      }
+    },
+    "lie": {
+      "version": "3.3.0",
+      "resolved": "https://registry.npmjs.org/lie/-/lie-3.3.0.tgz",
+      "integrity": "sha512-UaiMJzeWRlEujzAuw5LokY1L5ecNQYZKfmyZ9L7wDHb/p5etKaxXhohBcrw0EYby+G/NA52vRSN4N39dxHAIwQ==",
+      "requires": {
+        "immediate": "~3.0.5"
+      }
+    },
+    "listenercount": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/listenercount/-/listenercount-1.0.1.tgz",
+      "integrity": "sha1-hMinKrWcRyUyFIDJdeZQg0LnCTc="
+    },
+    "lodash.defaults": {
+      "version": "4.2.0",
+      "resolved": "https://registry.npmjs.org/lodash.defaults/-/lodash.defaults-4.2.0.tgz",
+      "integrity": "sha1-0JF4cW/+pN3p5ft7N/bwgCJ0WAw="
+    },
+    "lodash.difference": {
+      "version": "4.5.0",
+      "resolved": "https://registry.npmjs.org/lodash.difference/-/lodash.difference-4.5.0.tgz",
+      "integrity": "sha1-nMtOUF1Ia5FlE0V3KIWi3yf9AXw="
+    },
+    "lodash.escaperegexp": {
+      "version": "4.1.2",
+      "resolved": "https://registry.npmjs.org/lodash.escaperegexp/-/lodash.escaperegexp-4.1.2.tgz",
+      "integrity": "sha1-ZHYsSGGAglGKw99Mz11YhtriA0c="
+    },
+    "lodash.flatten": {
+      "version": "4.4.0",
+      "resolved": "https://registry.npmjs.org/lodash.flatten/-/lodash.flatten-4.4.0.tgz",
+      "integrity": "sha1-8xwiIlqWMtK7+OSt2+8kCqdlph8="
+    },
+    "lodash.groupby": {
+      "version": "4.6.0",
+      "resolved": "https://registry.npmjs.org/lodash.groupby/-/lodash.groupby-4.6.0.tgz",
+      "integrity": "sha1-Cwih3PaDl8OXhVwyOXg4Mt90A9E="
+    },
+    "lodash.isboolean": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/lodash.isboolean/-/lodash.isboolean-3.0.3.tgz",
+      "integrity": "sha1-bC4XHbKiV82WgC/UOwGyDV9YcPY="
+    },
+    "lodash.isequal": {
+      "version": "4.5.0",
+      "resolved": "https://registry.npmjs.org/lodash.isequal/-/lodash.isequal-4.5.0.tgz",
+      "integrity": "sha1-QVxEePK8wwEgwizhDtMib30+GOA="
+    },
+    "lodash.isfunction": {
+      "version": "3.0.9",
+      "resolved": "https://registry.npmjs.org/lodash.isfunction/-/lodash.isfunction-3.0.9.tgz",
+      "integrity": "sha512-AirXNj15uRIMMPihnkInB4i3NHeb4iBtNg9WRWuK2o31S+ePwwNmDPaTL3o7dTJ+VXNZim7rFs4rxN4YU1oUJw=="
+    },
+    "lodash.isnil": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/lodash.isnil/-/lodash.isnil-4.0.0.tgz",
+      "integrity": "sha1-SeKM1VkBNFjIFMVHnTxmOiG/qmw="
+    },
+    "lodash.isplainobject": {
+      "version": "4.0.6",
+      "resolved": "https://registry.npmjs.org/lodash.isplainobject/-/lodash.isplainobject-4.0.6.tgz",
+      "integrity": "sha1-fFJqUtibRcRcxpC4gWO+BJf1UMs="
+    },
+    "lodash.isundefined": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/lodash.isundefined/-/lodash.isundefined-3.0.1.tgz",
+      "integrity": "sha1-I+89lTVWUgOmbO/VuDD4SJEa+0g="
+    },
+    "lodash.union": {
+      "version": "4.6.0",
+      "resolved": "https://registry.npmjs.org/lodash.union/-/lodash.union-4.6.0.tgz",
+      "integrity": "sha1-SLtQiECfFvGCFmZkHETdGqrjzYg="
+    },
+    "lodash.uniq": {
+      "version": "4.5.0",
+      "resolved": "https://registry.npmjs.org/lodash.uniq/-/lodash.uniq-4.5.0.tgz",
+      "integrity": "sha1-0CJTc662Uq3BvILklFM5qEJ1R3M="
+    },
+    "minimatch": {
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-3.0.4.tgz",
+      "integrity": "sha512-yJHVQEhyqPLUTgt9B83PXu6W3rx4MvvHvSUvToogpwoGDOUQ+yDrR0HRot+yOCdCO7u4hX3pWft6kWBBcqh0UA==",
+      "requires": {
+        "brace-expansion": "^1.1.7"
+      }
+    },
+    "minimist": {
+      "version": "1.2.5",
+      "resolved": "https://registry.npmjs.org/minimist/-/minimist-1.2.5.tgz",
+      "integrity": "sha512-FM9nNUYrRBAELZQT3xeZQ7fmMOBg6nWNmJKTcgsJeaLstP/UODVpGsr5OhXhhXg6f+qtJ8uiZ+PUxkDWcgIXLw=="
+    },
+    "mkdirp": {
+      "version": "0.5.5",
+      "resolved": "https://registry.npmjs.org/mkdirp/-/mkdirp-0.5.5.tgz",
+      "integrity": "sha512-NKmAlESf6jMGym1++R0Ra7wvhV+wFW63FaSOFPwRahvea0gMUcGUhVeAg/0BC0wiv9ih5NYPB1Wn1UEI1/L+xQ==",
+      "requires": {
+        "minimist": "^1.2.5"
+      }
+    },
+    "normalize-path": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/normalize-path/-/normalize-path-3.0.0.tgz",
+      "integrity": "sha512-6eZs5Ls3WtCisHWp9S2GUy8dqkpGi4BVSz3GaqiE6ezub0512ESztXUwUB6C6IKbQkY2Pnb/mD4WYojCRwcwLA=="
+    },
+    "once": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/once/-/once-1.4.0.tgz",
+      "integrity": "sha1-WDsap3WWHUsROsF9nFC6753Xa9E=",
+      "requires": {
+        "wrappy": "1"
+      }
+    },
+    "pako": {
+      "version": "1.0.11",
+      "resolved": "https://registry.npmjs.org/pako/-/pako-1.0.11.tgz",
+      "integrity": "sha512-4hLB8Py4zZce5s4yd9XzopqwVv/yGNhV1Bl8NTmCq1763HeK2+EwVTv+leGeL13Dnh2wfbqowVPXCIO0z4taYw=="
+    },
+    "path-is-absolute": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/path-is-absolute/-/path-is-absolute-1.0.1.tgz",
+      "integrity": "sha1-F0uSaHNVNP+8es5r9TpanhtcX18="
+    },
+    "process-nextick-args": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/process-nextick-args/-/process-nextick-args-2.0.1.tgz",
+      "integrity": "sha512-3ouUOpQhtgrbOa17J7+uxOTpITYWaGP7/AhoR3+A+/1e9skrzelGi/dXzEYyvbxubEF6Wn2ypscTKiKJFFn1ag=="
+    },
+    "readable-stream": {
+      "version": "3.6.0",
+      "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-3.6.0.tgz",
+      "integrity": "sha512-BViHy7LKeTz4oNnkcLJ+lVSL6vpiFeX6/d3oSH8zCW7UxP2onchk+vTGB143xuFjHS3deTgkKoXXymXqymiIdA==",
+      "requires": {
+        "inherits": "^2.0.3",
+        "string_decoder": "^1.1.1",
+        "util-deprecate": "^1.0.1"
+      }
+    },
+    "rimraf": {
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-3.0.2.tgz",
+      "integrity": "sha512-JZkJMZkAGFFPP2YqXZXPbMlMBgsxzE8ILs4lMIX/2o0L9UBw9O/Y3o6wFw/i9YLapcUJWwqbi3kdxIPdC62TIA==",
+      "requires": {
+        "glob": "^7.1.3"
+      }
+    },
+    "safe-buffer": {
+      "version": "5.1.2",
+      "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.1.2.tgz",
+      "integrity": "sha512-Gd2UZBJDkXlY7GbJxfsE8/nvKkUEU1G38c1siN6QP6a9PT9MmHB8GnpscSmMJSoF8LOIrt8ud/wPtojys4G6+g=="
+    },
+    "saxes": {
+      "version": "5.0.1",
+      "resolved": "https://registry.npmjs.org/saxes/-/saxes-5.0.1.tgz",
+      "integrity": "sha512-5LBh1Tls8c9xgGjw3QrMwETmTMVk0oFgvrFSvWx62llR2hcEInrKNZ2GZCCuuy2lvWrdl5jhbpeqc5hRYKFOcw==",
+      "requires": {
+        "xmlchars": "^2.2.0"
+      }
+    },
+    "set-immediate-shim": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/set-immediate-shim/-/set-immediate-shim-1.0.1.tgz",
+      "integrity": "sha1-SysbJ+uAip+NzEgaWOXlb1mfP2E="
+    },
+    "setimmediate": {
+      "version": "1.0.5",
+      "resolved": "https://registry.npmjs.org/setimmediate/-/setimmediate-1.0.5.tgz",
+      "integrity": "sha1-KQy7Iy4waULX1+qbg3Mqt4VvgoU="
+    },
+    "string_decoder": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
+      "integrity": "sha512-n/ShnvDi6FHbbVfviro+WojiFzv+s8MPMHBczVePfUpDJLwoLT0ht1l4YwBCbi8pJAveEEdnkHyPyTP/mzRfwg==",
+      "requires": {
+        "safe-buffer": "~5.1.0"
+      }
+    },
+    "tar-stream": {
+      "version": "2.1.4",
+      "resolved": "https://registry.npmjs.org/tar-stream/-/tar-stream-2.1.4.tgz",
+      "integrity": "sha512-o3pS2zlG4gxr67GmFYBLlq+dM8gyRGUOvsrHclSkvtVtQbjV0s/+ZE8OpICbaj8clrX3tjeHngYGP7rweaBnuw==",
+      "requires": {
+        "bl": "^4.0.3",
+        "end-of-stream": "^1.4.1",
+        "fs-constants": "^1.0.0",
+        "inherits": "^2.0.3",
+        "readable-stream": "^3.1.1"
+      }
+    },
+    "tmp": {
+      "version": "0.2.1",
+      "resolved": "https://registry.npmjs.org/tmp/-/tmp-0.2.1.tgz",
+      "integrity": "sha512-76SUhtfqR2Ijn+xllcI5P1oyannHNHByD80W1q447gU3mp9G9PSpGdWmjUOHRDPiHYacIk66W7ubDTuPF3BEtQ==",
+      "requires": {
+        "rimraf": "^3.0.0"
+      }
+    },
+    "traverse": {
+      "version": "0.3.9",
+      "resolved": "https://registry.npmjs.org/traverse/-/traverse-0.3.9.tgz",
+      "integrity": "sha1-cXuPIgzAu3tE5AUUwisui7xw2Lk="
+    },
+    "unzipper": {
+      "version": "0.10.11",
+      "resolved": "https://registry.npmjs.org/unzipper/-/unzipper-0.10.11.tgz",
+      "integrity": "sha512-+BrAq2oFqWod5IESRjL3S8baohbevGcVA+teAIOYWM3pDVdseogqbzhhvvmiyQrUNKFUnDMtELW3X8ykbyDCJw==",
+      "requires": {
+        "big-integer": "^1.6.17",
+        "binary": "~0.3.0",
+        "bluebird": "~3.4.1",
+        "buffer-indexof-polyfill": "~1.0.0",
+        "duplexer2": "~0.1.4",
+        "fstream": "^1.0.12",
+        "graceful-fs": "^4.2.2",
+        "listenercount": "~1.0.1",
+        "readable-stream": "~2.3.6",
+        "setimmediate": "~1.0.4"
+      },
+      "dependencies": {
+        "readable-stream": {
+          "version": "2.3.7",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.7.tgz",
+          "integrity": "sha512-Ebho8K4jIbHAxnuxi7o42OrZgF/ZTNcsZj6nRKyUmkhLFq8CHItp/fy6hQZuZmP/n3yZ9VBUbp4zz/mX8hmYPw==",
+          "requires": {
+            "core-util-is": "~1.0.0",
+            "inherits": "~2.0.3",
+            "isarray": "~1.0.0",
+            "process-nextick-args": "~2.0.0",
+            "safe-buffer": "~5.1.1",
+            "string_decoder": "~1.1.1",
+            "util-deprecate": "~1.0.1"
+          }
+        }
+      }
+    },
+    "util-deprecate": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/util-deprecate/-/util-deprecate-1.0.2.tgz",
+      "integrity": "sha1-RQ1Nyfpw3nMnYvvS1KKJgUGaDM8="
+    },
+    "uuid": {
+      "version": "7.0.3",
+      "resolved": "https://registry.npmjs.org/uuid/-/uuid-7.0.3.tgz",
+      "integrity": "sha512-DPSke0pXhTZgoF/d+WSt2QaKMCFSfx7QegxEWT+JOuHF5aWrKEn0G+ztjuJg/gG8/ItK+rbPCD/yNv8yyih6Cg=="
+    },
+    "wrappy": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
+      "integrity": "sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8="
+    },
+    "xlsx-import": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/xlsx-import/-/xlsx-import-2.3.0.tgz",
+      "integrity": "sha512-LpkE2gCkfKM7RW9X3fcinhrlvBk8P4vLtfDDTq4dtaByleGteTF40nZVqZlJe+kKSgn+SjAClwUpIaLD404qpQ==",
+      "requires": {
+        "exceljs": "^4.1.1"
+      }
+    },
+    "xmlchars": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/xmlchars/-/xmlchars-2.2.0.tgz",
+      "integrity": "sha512-JZnDKK8B0RCDw84FNdDAIpZK+JuJw+s7Lz8nksI7SIuU3UXJJslUthsi+uWBUYOwPFwW7W7PRLRfUKpxjtjFCw=="
+    },
+    "zip-stream": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/zip-stream/-/zip-stream-3.0.1.tgz",
+      "integrity": "sha512-r+JdDipt93ttDjsOVPU5zaq5bAyY+3H19bDrThkvuVxC0xMQzU1PJcS6D+KrP3u96gH9XLomcHPb+2skoDjulQ==",
+      "requires": {
+        "archiver-utils": "^2.1.0",
+        "compress-commons": "^3.0.0",
+        "readable-stream": "^3.6.0"
+      }
+    }
+  }
+}
diff --git a/samples/nodejs/package.json b/samples/nodejs/package.json
new file mode 100644
index 0000000..2f0618b
--- /dev/null
+++ b/samples/nodejs/package.json
@@ -0,0 +1,14 @@
+{
+  "name": "@xlsx-import/samples-nodejs",
+  "version": "0.0.0",
+  "description": "Nodejs example usage of xlsx-import",
+  "main": "index.js",
+  "scripts": {
+    "start": "node index.js"
+  },
+  "author": "Paweł Siemienik <siemienik.pawel@gmail.com>",
+  "license": "MIT",
+  "dependencies": {
+    "xlsx-import": "^2.3.0"
+  }
+}
diff --git a/samples/nodejs/result.json b/samples/nodejs/result.json
new file mode 100644
index 0000000..3328878
--- /dev/null
+++ b/samples/nodejs/result.json
@@ -0,0 +1,42 @@
+{
+  date: 2020-10-08T00:00:00.000Z,
+  dueDate: 2020-10-29T00:00:00.000Z,
+  seller: {
+    name: 'Krupnik LTD.',
+    taxIdNumber: '123456789',
+    address: 'ul. Usbewifi 5/G, MiastoNaK',
+    accountNo: 'PL 12 1234 1234 1234 1234 1234 1234'
+  },
+  buyer: {
+    name: 'Bigos INC.',
+    taxIdNumber: '987654321',
+    address: 'ul. Agiede 2020, MiastoNaK'
+  },
+  items: [
+    {
+      item: 'Mleczko do prania',
+      unitPrice: 16.45,
+      quantity: 2,
+      price: 32.9
+    },
+    {
+      item: 'Płyn do płukania',
+      unitPrice: 14.55,
+      quantity: 1,
+      price: 14.55
+    },
+    {
+      item: 'Pokarm dla smoka',
+      unitPrice: 79.99,
+      quantity: 10,
+      price: 799.9
+    },
+    {
+      item: 'Instrukcja jak latać na smoku',
+      unitPrice: 19.89,
+      quantity: 1,
+      price: 19.89
+    }
+  ],
+  total: 867.24
+}
diff --git a/src/mappers/index.ts b/src/mappers/index.ts
index dcf549b..87cd520 100644
--- a/src/mappers/index.ts
+++ b/src/mappers/index.ts
@@ -1,4 +1,3 @@
-import { ValueMapper } from '../abstracts/ValueMapper';
 import { stringMapper } from './stringMapper';
 
 /** probably `MAPPER_DEFAULT` should never be changed. Designed for internal usages when mapper isn't precised. */