@@ -67,5 +67,5 @@ jobs:
           python-version: ${{ matrix.python-version }}
       - name: Run tests
         run: |
-          pip install ".[test]"
-          tox
+          pip install ".[unit-test]"
+          make test-unit
@@ -3,8 +3,7 @@
 ## Source of Truth
 
 - This is the official synchronous Python SDK for the Linode API. Supported
-  Python versions come from [pyproject.toml](pyproject.toml) (`>=3.10`); do not
-  infer support from the older environment names still present in [tox.ini](tox.ini).
+  Python versions come from [pyproject.toml](pyproject.toml) (`>=3.10`).
 - Make changes only in canonical source trees such as `linode_api4/`, `test/`,
   `docs/`, `examples/`, and `.github/`. Do not edit generated copies or output in
   `build/`, `dist/`, `docs/build/`, `docs/_build/`, or `linode_api4.egg-info/`.
 
@@ -102,14 +102,13 @@ Tests
 -----
 
 Tests live in the ``test`` directory.  When invoking tests, make sure you are
-in the root directory of this project.  To run the full suite across all
-supported python versions, use tox_:
+in the root directory of this project.  Install unit-test dependencies and run
+the mocked unit suite with:
 
 .. code-block:: shell
 
-   tox
-
-Running tox also runs pylint and coverage reports.
+   python3 -m pip install -e ".[unit-test]"
+   make test-unit
 
 The test suite uses fixtures stored as JSON in ``test/fixtures``.  These files
 contain sanitized JSON responses from the API - the file name is the URL called
@@ -131,8 +130,6 @@ from the api base url that should be returned, for example::
      linode = self.client.linode.instance_create('g6-standard-2', 'us-east')
      self.assertEqual(linode.id, 123) # passes
 
-.. _tox: http://tox.readthedocs.io
-
 
 Integration Tests
 -----------------
 
@@ -35,6 +35,27 @@ def create(self, region, **kwargs):
         :param ipv4: A reserved IPv4 address to assign to this NodeBalancer.
                      NOTE: Reserved IP feature may not currently be available to all users.
         :type ipv4: str
+        :param type: The NodeBalancer type. Supported values include
+                     ``common``, ``premium``, ``premium_40gb``, and
+                     ``enterprise``. This cannot be changed after creation.
+                     NOTE: Creating premium or enterprise NodeBalancers may not
+                     currently be available to all users.
+        :type type: str
+        :param backend_connectivity: How this NodeBalancer communicates with
+                     backends (``legacy``, ``ipv6``, or ``vpc``). If omitted,
+                     the API infers a value from ``vpcs`` or config nodes, or
+                     returns ``undefined`` until the first node is added.
+                     ``undefined`` cannot be sent by clients. This cannot be
+                     changed after creation.
+                     NOTE: This field may not currently be available to all users.
+        :type backend_connectivity: NodeBalancerBackendConnectivity | str
+        :param vpcs: VPC attachments for this NodeBalancer. Required when
+                     ``backend_connectivity`` is ``vpc``.
+        :type vpcs: list[dict]
+        :param configs: NodeBalancer configs and optional nodes to create
+                     with this NodeBalancer. Node addresses must match the
+                     selected or inferred backend connectivity.
+        :type configs: list[dict]
 
         :returns: The new NodeBalancer
         :rtype: NodeBalancer
 
@@ -790,6 +790,42 @@ class UpgradeInterfacesResult(JSONObject):
     )
 
 
+@dataclass
+class InstanceBackupSchedule(JSONObject):
+    """
+    InstanceBackupSchedule represents when automatic backups of a Linode Instance are taken.
+    """
+
+    include_none_values = True
+
+    day: Optional[str] = None
+    window: Optional[str] = None
+
+
+@dataclass
+class InstanceBackupsOptions(JSONObject):
+    """
+    InstanceBackupsOptions is used to update the backup settings of a Linode Instance.
+    """
+
+    enabled: bool = False
+    schedule: Optional[InstanceBackupSchedule] = None
+
+
+@dataclass
+class InstanceBackups(JSONObject):
+    """
+    InstanceBackups represents the backup settings and status of a Linode Instance.
+    """
+
+    put_class = InstanceBackupsOptions
+
+    enabled: bool = False
+    available: bool = False
+    schedule: Optional[InstanceBackupSchedule] = None
+    last_successful: Optional[str] = None
+
+
 class Instance(Base):
     """
     A Linode Instance.
@@ -811,7 +847,7 @@ class Instance(Base):
         "disks": Property(derived_class=Disk),
         "configs": Property(derived_class=Config),
         "type": Property(slug_relationship=Type),
-        "backups": Property(mutable=True),
+        "backups": Property(mutable=True, json_object=InstanceBackups),
         "ipv4": Property(unordered=True),
         "ipv6": Property(),
         "hypervisor": Property(),
 
@@ -277,8 +277,8 @@ class MonitorDashboard(Base):
         "id": Property(identifier=True),
         "created": Property(is_datetime=True),
         "label": Property(),
-        "service_type": Property(ServiceType),
-        "type": Property(DashboardType),
+        "service_type": Property(),
+        "type": Property(),
         "group_by": Property(),
         "widgets": Property(json_object=DashboardWidget),
         "updated": Property(is_datetime=True),
@@ -295,7 +295,7 @@ class MonitorService(Base):
     api_endpoint = "/monitor/services/{service_type}"
     id_attribute = "service_type"
     properties = {
-        "service_type": Property(ServiceType),
+        "service_type": Property(),
         "label": Property(),
         "alert": Property(json_object=ServiceAlert),
     }
@@ -496,7 +496,7 @@ class AlertDefinition(DerivedBase):
         "entity_ids": Property(mutable=True),
         "description": Property(mutable=True),
         "service_class": Property(alias_of="class"),
-        "scope": Property(AlertScope),
+        "scope": Property(),
         "regions": Property(mutable=True),
         "entities": Property(json_object=AlertEntities),
         "channel_ids": Property(mutable=True),
 
@@ -7,6 +7,16 @@
 from linode_api4.objects.dbase import DerivedBase
 from linode_api4.objects.networking import Firewall, IPAddress
 from linode_api4.objects.region import Region
+from linode_api4.objects.serializable import StrEnum
+
+
+class NodeBalancerBackendConnectivity(StrEnum):
+    """Backend connectivity modes accepted when creating a NodeBalancer."""
+
+    IPV6 = "ipv6"
+    LEGACY = "legacy"
+    UNDEFINED = "undefined"
+    VPC = "vpc"
 
 
 class NodeBalancerType(Base):
@@ -162,8 +172,10 @@ def node_create(self, label, address, **kwargs):
 
         API documentation: https://techdocs.akamai.com/linode-api/reference/post-node-balancer-node
 
-        :param address: The private IP Address where this backend can be reached.
-                        This must be a private IP address.
+        :param address: The address and port where this backend can be reached.
+                        The address may be a private IPv4 address, a public
+                        IPv6 address, or a VPC address. The address type must
+                        match this NodeBalancer's ``backend_connectivity``.
         :type address: str
 
         :param label: The label for this node. This is for display purposes only.
@@ -255,6 +267,9 @@ class NodeBalancer(Base):
         "tags": Property(mutable=True, unordered=True),
         "client_udp_sess_throttle": Property(mutable=True),
         "locks": Property(unordered=True),
+        "type": Property(),
+        "backend_connectivity": Property(),
+        "backend_ipv6_prefix": Property(),
     }
 
     # create derived objects
 
@@ -35,32 +35,38 @@ dependencies = ["requests", "polling", "deprecated"]
 dynamic = ["version"]
 
 [project.optional-dependencies]
-test = ["tox>=4.4.0"]
-
-dev = [
-    "tox>=4.4.0",
-    "mock>=5.0.0",
+test-shared = [
     "pytest>=7.3.1",
     "httpretty>=1.1.4",
+    "pytest-rerunfailures",
+]
+unit-test = [
+    "linode_api4[test-shared]",
+    "mock>=5.0.0",
+]
+int-test = [
+    "linode_api4[test-shared]",
+    "cryptography",
+]
+lint = [
     "black>=23.1.0",
     "isort>=5.12.0",
     "autoflake>=2.0.1",
     "pylint",
     "twine>=4.0.2",
     "build>=0.10.0",
-    "Sphinx>=6.0.0",
-    "sphinx-autobuild>=2021.3.14",
-    "sphinxcontrib-fulltoc>=1.2.0",
-    "build>=0.10.0",
-    "twine>=4.0.2",
-    "pytest-rerunfailures",
 ]
-
 doc = [
     "Sphinx>=6.0.0",
     "sphinx-autobuild>=2021.3.14",
     "sphinxcontrib-fulltoc>=1.2.0",
 ]
+dev = [
+    "linode_api4[unit-test]",
+    "linode_api4[int-test]",
+    "linode_api4[lint]",
+    "linode_api4[doc]",
+]
 
 [project.urls]
 Homepage = "https://github.com/linode/linode_api4-python"
 
@@ -19,6 +19,8 @@
       "label": "linode123",
       "backups": {
         "enabled": true,
+        "available": true,
+        "last_successful": "2018-01-01T00:01:01",
         "schedule": {
           "window": "W02",
           "day": "Scheduling"
 
@@ -8,6 +8,9 @@
       "ipv4": "203.0.113.1",
       "ipv6": null,
       "label": "balancer12345",
+      "type": "premium",
+      "backend_connectivity": "ipv6",
+      "backend_ipv6_prefix": "2600:3c22:1:20:0:3039::/96",
       "region": "us-east",
       "tags": [
         "example tag",