diff --git a/.github/workflows/html.yaml b/.github/workflows/html.yaml
index d0084ae032..580962771e 100644
--- a/.github/workflows/html.yaml
+++ b/.github/workflows/html.yaml
@@ -23,11 +23,13 @@ jobs:
       INVENTREE_MEDIA_ROOT: ./media
       INVENTREE_STATIC_ROOT: ./static
     steps:
-      - name: Install node.js
-        uses: actions/setup-node@v2
-      - run: npm install
       - name: Checkout Code
         uses: actions/checkout@v2
+      - name: Install node.js
+        uses: actions/setup-node@v2
+        with:
+          node-version: '16'
+      - run: npm install
       - name: Setup Python
         uses: actions/setup-python@v2
         with:
@@ -41,7 +43,6 @@ jobs:
           invoke static
       - name: Check HTML Files
         run: |
-          npm install markuplint
           npx markuplint InvenTree/build/templates/build/*.html
           npx markuplint InvenTree/company/templates/company/*.html
           npx markuplint InvenTree/order/templates/order/*.html
diff --git a/.github/workflows/javascript.yaml b/.github/workflows/javascript.yaml
index a07b516ac6..98251b2426 100644
--- a/.github/workflows/javascript.yaml
+++ b/.github/workflows/javascript.yaml
@@ -23,11 +23,13 @@ jobs:
       INVENTREE_MEDIA_ROOT: ./media
       INVENTREE_STATIC_ROOT: ./static
     steps:
-      - name: Install node.js
-        uses: actions/setup-node@v2
-      - run: npm install
       - name: Checkout Code
         uses: actions/checkout@v2
+      - name: Install node.js
+        uses: actions/setup-node@v2
+        with:
+          node-version: '16'
+      - run: npm install
       - name: Setup Python
         uses: actions/setup-python@v2
         with:
@@ -45,6 +47,5 @@ jobs:
           python check_js_templates.py
       - name: Lint Javascript Files
         run: |
-          npm install eslint eslint-config-google
           invoke render-js-files
           npx eslint js_tmp/*.js
\ No newline at end of file
diff --git a/.gitignore b/.gitignore
index 420524d06f..74669a5756 100644
--- a/.gitignore
+++ b/.gitignore
@@ -78,5 +78,4 @@ locale_stats.json
 
 # node.js
 package-lock.json
-package.json
 node_modules/
\ No newline at end of file
diff --git a/InvenTree/InvenTree/models.py b/InvenTree/InvenTree/models.py
index 0448a69781..b42d54cbe9 100644
--- a/InvenTree/InvenTree/models.py
+++ b/InvenTree/InvenTree/models.py
@@ -49,6 +49,9 @@ class ReferenceIndexingMixin(models.Model):
     """
     A mixin for keeping track of numerical copies of the "reference" field.
 
+    !!DANGER!! always add `ReferenceIndexingSerializerMixin`to all your models serializers to
+    ensure the reference field is not too big
+
     Here, we attempt to convert a "reference" field value (char) to an integer,
     for performing fast natural sorting.
 
@@ -69,22 +72,25 @@ class ReferenceIndexingMixin(models.Model):
 
         reference = getattr(self, 'reference', '')
 
-        # Default value if we cannot convert to an integer
-        ref_int = 0
+        self.reference_int = extract_int(reference)
 
-        # Look at the start of the string - can it be "integerized"?
-        result = re.match(r"^(\d+)", reference)
+    reference_int = models.BigIntegerField(default=0)
 
-        if result and len(result.groups()) == 1:
-            ref = result.groups()[0]
-            try:
-                ref_int = int(ref)
-            except:
-                ref_int = 0
 
-        self.reference_int = ref_int
+def extract_int(reference):
+    # Default value if we cannot convert to an integer
+    ref_int = 0
 
-    reference_int = models.IntegerField(default=0)
+    # Look at the start of the string - can it be "integerized"?
+    result = re.match(r"^(\d+)", reference)
+
+    if result and len(result.groups()) == 1:
+        ref = result.groups()[0]
+        try:
+            ref_int = int(ref)
+        except:
+            ref_int = 0
+    return ref_int
 
 
 class InvenTreeAttachment(models.Model):
diff --git a/InvenTree/InvenTree/serializers.py b/InvenTree/InvenTree/serializers.py
index 3785cfb292..59ba0295cb 100644
--- a/InvenTree/InvenTree/serializers.py
+++ b/InvenTree/InvenTree/serializers.py
@@ -16,6 +16,7 @@ from django.conf import settings
 from django.contrib.auth.models import User
 from django.core.exceptions import ValidationError as DjangoValidationError
 from django.utils.translation import ugettext_lazy as _
+from django.db import models
 
 from djmoney.contrib.django_rest_framework.fields import MoneyField
 from djmoney.money import Money
@@ -27,6 +28,8 @@ from rest_framework.fields import empty
 from rest_framework.exceptions import ValidationError
 from rest_framework.serializers import DecimalField
 
+from .models import extract_int
+
 
 class InvenTreeMoneySerializer(MoneyField):
     """
@@ -239,6 +242,17 @@ class InvenTreeModelSerializer(serializers.ModelSerializer):
         return data
 
 
+class ReferenceIndexingSerializerMixin():
+    """
+    This serializer mixin ensures the the reference is not to big / small
+    for the BigIntegerField
+    """
+    def validate_reference(self, value):
+        if extract_int(value) > models.BigIntegerField.MAX_BIGINT:
+            raise serializers.ValidationError('reference is to to big')
+        return value
+
+
 class InvenTreeAttachmentSerializerField(serializers.FileField):
     """
     Override the DRF native FileField serializer,
diff --git a/InvenTree/build/migrations/0034_alter_build_reference_int.py b/InvenTree/build/migrations/0034_alter_build_reference_int.py
new file mode 100644
index 0000000000..8b14d3812e
--- /dev/null
+++ b/InvenTree/build/migrations/0034_alter_build_reference_int.py
@@ -0,0 +1,18 @@
+# Generated by Django 3.2.5 on 2021-12-01 21:39
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('build', '0033_auto_20211128_0151'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='build',
+            name='reference_int',
+            field=models.BigIntegerField(default=0),
+        ),
+    ]
diff --git a/InvenTree/build/serializers.py b/InvenTree/build/serializers.py
index 4ef4157bb6..2ea898f66c 100644
--- a/InvenTree/build/serializers.py
+++ b/InvenTree/build/serializers.py
@@ -16,7 +16,7 @@ from rest_framework import serializers
 from rest_framework.serializers import ValidationError
 
 from InvenTree.serializers import InvenTreeModelSerializer, InvenTreeAttachmentSerializer
-from InvenTree.serializers import UserSerializerBrief
+from InvenTree.serializers import UserSerializerBrief, ReferenceIndexingSerializerMixin
 
 import InvenTree.helpers
 from InvenTree.serializers import InvenTreeDecimalField
@@ -32,7 +32,7 @@ from users.serializers import OwnerSerializer
 from .models import Build, BuildItem, BuildOrderAttachment
 
 
-class BuildSerializer(InvenTreeModelSerializer):
+class BuildSerializer(ReferenceIndexingSerializerMixin, InvenTreeModelSerializer):
     """
     Serializes a Build object
     """
diff --git a/InvenTree/order/migrations/0054_auto_20211201_2139.py b/InvenTree/order/migrations/0054_auto_20211201_2139.py
new file mode 100644
index 0000000000..8a66bbea12
--- /dev/null
+++ b/InvenTree/order/migrations/0054_auto_20211201_2139.py
@@ -0,0 +1,23 @@
+# Generated by Django 3.2.5 on 2021-12-01 21:39
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('order', '0053_auto_20211128_0151'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='purchaseorder',
+            name='reference_int',
+            field=models.BigIntegerField(default=0),
+        ),
+        migrations.AlterField(
+            model_name='salesorder',
+            name='reference_int',
+            field=models.BigIntegerField(default=0),
+        ),
+    ]
diff --git a/InvenTree/order/serializers.py b/InvenTree/order/serializers.py
index b336042684..11508070d5 100644
--- a/InvenTree/order/serializers.py
+++ b/InvenTree/order/serializers.py
@@ -26,6 +26,7 @@ from InvenTree.helpers import normalize
 from InvenTree.serializers import InvenTreeModelSerializer
 from InvenTree.serializers import InvenTreeDecimalField
 from InvenTree.serializers import InvenTreeMoneySerializer
+from InvenTree.serializers import ReferenceIndexingSerializerMixin
 from InvenTree.status_codes import StockStatus
 
 import order.models
@@ -38,10 +39,8 @@ import stock.serializers
 from users.serializers import OwnerSerializer
 
 
-class POSerializer(InvenTreeModelSerializer):
-    """
-    Serializer for a PurchaseOrder object
-    """
+class POSerializer(ReferenceIndexingSerializerMixin, InvenTreeModelSerializer):
+    """ Serializer for a PurchaseOrder object """
 
     def __init__(self, *args, **kwargs):
 
@@ -395,7 +394,7 @@ class POAttachmentSerializer(InvenTreeAttachmentSerializer):
         ]
 
 
-class SalesOrderSerializer(InvenTreeModelSerializer):
+class SalesOrderSerializer(ReferenceIndexingSerializerMixin, InvenTreeModelSerializer):
     """
     Serializers for the SalesOrder object
     """
diff --git a/InvenTree/order/test_api.py b/InvenTree/order/test_api.py
index c8cb30b0b7..2ea2086431 100644
--- a/InvenTree/order/test_api.py
+++ b/InvenTree/order/test_api.py
@@ -106,6 +106,25 @@ class PurchaseOrderTest(OrderTest):
         self.assertEqual(data['pk'], 1)
         self.assertEqual(data['description'], 'Ordering some screws')
 
+    def test_po_reference(self):
+        """test that a reference with a too big / small reference is not possible"""
+        # get permissions
+        self.assignRole('purchase_order.add')
+
+        url = reverse('api-po-list')
+        huge_numer = 9223372036854775808
+
+        # too big
+        self.post(
+            url,
+            {
+                'supplier': 1,
+                'reference': huge_numer,
+                'description': 'PO not created via the API',
+            },
+            expected_code=400
+        )
+
     def test_po_attachments(self):
 
         url = reverse('api-po-attachment-list')
diff --git a/InvenTree/stock/models.py b/InvenTree/stock/models.py
index 8457ca39ab..0aa63687c9 100644
--- a/InvenTree/stock/models.py
+++ b/InvenTree/stock/models.py
@@ -7,7 +7,6 @@ Stock database model definitions
 from __future__ import unicode_literals
 
 import os
-import re
 
 from django.utils.translation import gettext_lazy as _
 from django.core.exceptions import ValidationError, FieldError
@@ -39,6 +38,7 @@ import label.models
 from InvenTree.status_codes import StockStatus, StockHistoryCode
 from InvenTree.models import InvenTreeTree, InvenTreeAttachment
 from InvenTree.fields import InvenTreeModelMoneyField, InvenTreeURLField
+from InvenTree.serializers import extract_int
 
 from users.models import Owner
 
@@ -236,17 +236,7 @@ class StockItem(MPTTModel):
         serial_int = 0
 
         if serial is not None:
-
-            serial = str(serial)
-
-            # Look at the start of the string - can it be "integerized"?
-            result = re.match(r'^(\d+)', serial)
-
-            if result and len(result.groups()) == 1:
-                try:
-                    serial_int = int(result.groups()[0])
-                except:
-                    serial_int = 0
+            serial_int = extract_int(str(serial))
 
         self.serial_int = serial_int
 
diff --git a/InvenTree/stock/serializers.py b/InvenTree/stock/serializers.py
index c74d674275..9bd5ea64be 100644
--- a/InvenTree/stock/serializers.py
+++ b/InvenTree/stock/serializers.py
@@ -32,7 +32,7 @@ from company.serializers import SupplierPartSerializer
 
 import InvenTree.helpers
 import InvenTree.serializers
-from InvenTree.serializers import InvenTreeDecimalField
+from InvenTree.serializers import InvenTreeDecimalField, extract_int
 
 from part.serializers import PartBriefSerializer
 
@@ -73,6 +73,11 @@ class StockItemSerializerBrief(InvenTree.serializers.InvenTreeModelSerializer):
             'uid',
         ]
 
+    def validate_serial(self, value):
+        if extract_int(value) > 2147483647:
+            raise serializers.ValidationError('serial is to to big')
+        return value
+
 
 class StockItemSerializer(InvenTree.serializers.InvenTreeModelSerializer):
     """ Serializer for a StockItem:
diff --git a/package.json b/package.json
new file mode 100644
index 0000000000..b4f14ec92f
--- /dev/null
+++ b/package.json
@@ -0,0 +1,7 @@
+{
+  "dependencies": {
+    "eslint": "^8.3.0",
+    "eslint-config-google": "^0.14.0",
+    "markuplint": "^1.11.4"
+  }
+}