diff --git a/mix.exs b/mix.exs
index d8547ca..ce2b0ab 100644
--- a/mix.exs
+++ b/mix.exs
@@ -94,7 +94,7 @@ defmodule Diffo.MixProject do
       {:ash_outstanding, "~> 0.2.3"},
       {:ash_jason, "~> 3.0"},
       {:ash_state_machine, "~> 0.2.12"},
-      {:ash_neo4j, ash_neo4j_version("~> 0.2.14")},
+      {:ash_neo4j, ash_neo4j_version("~> 0.2.15")},
       {:ash, ash_version("~> 3.0 and >= 3.19.1")},
       {:uuid, "~> 1.1"},
       {:igniter, ">= 0.6.29 and < 1.0.0-0",
diff --git a/mix.lock b/mix.lock
index 4f6bc67..842db11 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,7 +1,7 @@
 %{
   "ash": {:hex, :ash, "3.19.3", "58b1bb3aea3d1d45d1c990059ffd0753409cc92fc4afe387376cb155e2a8c2a0", [:mix], [{:crux, ">= 0.1.2 and < 1.0.0-0", [hex: :crux, repo: "hexpm", optional: false]}, {:decimal, "~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:ecto, "~> 3.7", [hex: :ecto, repo: "hexpm", optional: false]}, {:ets, "~> 0.8", [hex: :ets, repo: "hexpm", optional: false]}, {:igniter, ">= 0.6.29 and < 1.0.0-0", [hex: :igniter, repo: "hexpm", optional: true]}, {:jason, ">= 1.0.0", [hex: :jason, repo: "hexpm", optional: false]}, {:picosat_elixir, "~> 0.2", [hex: :picosat_elixir, repo: "hexpm", optional: true]}, {:plug, ">= 0.0.0", [hex: :plug, repo: "hexpm", optional: true]}, {:reactor, "~> 1.0", [hex: :reactor, repo: "hexpm", optional: false]}, {:simple_sat, ">= 0.1.1 and < 1.0.0-0", [hex: :simple_sat, repo: "hexpm", optional: true]}, {:spark, ">= 2.3.14 and < 3.0.0-0", [hex: :spark, repo: "hexpm", optional: false]}, {:splode, "~> 0.3", [hex: :splode, repo: "hexpm", optional: false]}, {:stream_data, "~> 1.0", [hex: :stream_data, repo: "hexpm", optional: false]}, {:telemetry, "~> 1.1", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "94b628319f2e144affaf1f8008277bad3340a198d48e6d2ed372990ac1643f9b"},
   "ash_jason": {:hex, :ash_jason, "3.1.0", "84a88dfe5e25a20d55cf2d2664885cd086fa45871e8777aedc3ad96a282e2a6f", [:mix], [{:ash, ">= 3.6.2 and < 4.0.0-0", [hex: :ash, repo: "hexpm", optional: false]}, {:jason, "~> 1.4", [hex: :jason, repo: "hexpm", optional: false]}, {:spark, ">= 2.1.21 and < 3.0.0", [hex: :spark, repo: "hexpm", optional: false]}], "hexpm", "71e6bbc421fb2cf7079f8804814145cca458116c839fc798f9606b806e07eb2b"},
-  "ash_neo4j": {:hex, :ash_neo4j, "0.2.14", "c6bb1b895510ab423afc4225840d4c4e94716490316bf75aa8da1da464f53e0a", [:mix], [{:ash, ">= 3.19.1 and < 4.0.0-0", [hex: :ash, repo: "hexpm", optional: false]}, {:bolty, ">= 0.0.7", [hex: :bolty, repo: "hexpm", optional: false]}, {:igniter, ">= 0.6.29 and < 1.0.0-0", [hex: :igniter, repo: "hexpm", optional: true]}, {:jason, "~> 1.4", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "888bd4a9fcc3c231642dfb4cb9110d9aef8a57ff61f16f078bfd278cde17cd69"},
+  "ash_neo4j": {:hex, :ash_neo4j, "0.2.15", "1380f3a3f6b43fb346308808d621bd19b891b859431fd4b1ac26472fcee5b372", [:mix], [{:ash, ">= 3.19.1 and < 4.0.0-0", [hex: :ash, repo: "hexpm", optional: false]}, {:bolty, ">= 0.0.7", [hex: :bolty, repo: "hexpm", optional: false]}, {:igniter, ">= 0.6.29 and < 1.0.0-0", [hex: :igniter, repo: "hexpm", optional: true]}, {:jason, "~> 1.4", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "8be0a84e02ce70d691b3619c1f7cb7c8e1d9daf001673a227b27762f3690ac40"},
   "ash_outstanding": {:hex, :ash_outstanding, "0.2.4", "c72b91f1b8e4859fb033eddf66d0ba36cfd8af0c2a9748c7ef9e6ccfdb5d093d", [:mix], [{:ash, ">= 3.6.2 and < 4.0.0-0", [hex: :ash, repo: "hexpm", optional: false]}, {:outstanding, "~> 0.2.4", [hex: :outstanding, repo: "hexpm", optional: false]}], "hexpm", "64ba8f582ce69c9050352c75f0895db186c7a56f35039dab34c8e1ab7516f9ce"},
   "ash_state_machine": {:hex, :ash_state_machine, "0.2.12", "c0f7ebb8a176584f70c6ed196b7d0118c930d73e0590ade705d2dddc48aa7311", [:mix], [{:ash, ">= 3.4.66 and < 4.0.0-0", [hex: :ash, repo: "hexpm", optional: false]}], "hexpm", "394ce761ce82358e3c715e1cae6c5cf1390be27c03a8b661f2e5a2fda849873d"},
   "bolty": {:hex, :bolty, "0.0.7", "257889f71bd16a9291bda8290c1018123c4084c8761f905b97d7176e65d8b111", [:mix], [{:db_connection, "~> 2.7.0", [hex: :db_connection, repo: "hexpm", optional: false]}, {:jason, "~> 1.4", [hex: :jason, repo: "hexpm", optional: true]}, {:poison, "~> 6.0", [hex: :poison, repo: "hexpm", optional: true]}], "hexpm", "fc8f88b86d292ad1336f9e246a6c0452e64774b38fac0351c141549420946e5e"},
diff --git a/test/assigner/assigner_test.exs b/test/assigner/assigner_test.exs
index 4ca6133..4ac163c 100644
--- a/test/assigner/assigner_test.exs
+++ b/test/assigner/assigner_test.exs
@@ -10,7 +10,7 @@ defmodule Diffo.Test.AssignerTest do
   alias Diffo.Provider.Assignment
 
   alias Diffo.Test.Characteristics
-  alias Diffo.Test.Domain
+  alias Diffo.Test.Servo
   alias Diffo.Test.Card
 
   setup_all do
@@ -25,7 +25,7 @@ defmodule Diffo.Test.AssignerTest do
 
   describe "build card" do
     test "create a card" do
-      {:ok, card} = Domain.build_card(%{})
+      {:ok, card} = Servo.build_card(%{})
 
       # check the instance is a Card
       assert is_struct(card, Card)
@@ -67,14 +67,14 @@ defmodule Diffo.Test.AssignerTest do
     end
 
     test "define card" do
-      {:ok, card} = Domain.build_card(%{})
+      {:ok, card} = Servo.build_card(%{})
 
       updates = [
         card: [family: :ISAM, model: "EBLT48", technology: :adsl2Plus],
         ports: [first: 1, last: 48, free: 48, type: "ADSL2+"]
       ]
 
-      {:ok, card} = Domain.define_card(card, %{characteristic_value_updates: updates})
+      {:ok, card} = Servo.define_card(card, %{characteristic_value_updates: updates})
 
       encoding = Jason.encode!(card) |> Diffo.Util.summarise_dates()
 
@@ -83,19 +83,19 @@ defmodule Diffo.Test.AssignerTest do
     end
 
     test "auto assign port to resource" do
-      {:ok, assignee} = Domain.build_shelf()
+      {:ok, assignee} = Servo.build_shelf()
 
-      {:ok, card} = Domain.build_card(%{})
+      {:ok, card} = Servo.build_card(%{})
 
       updates = [
         card: [family: :ISAM, model: "EBLT48", technology: :adsl2Plus],
         ports: [first: 1, last: 48, free: 48, type: "ADSL2+"]
       ]
 
-      {:ok, card} = Domain.define_card(card, %{characteristic_value_updates: updates})
+      {:ok, card} = Servo.define_card(card, %{characteristic_value_updates: updates})
 
       {:ok, card} =
-        Domain.assign_port(card, %{
+        Servo.assign_port(card, %{
           assignment: %Assignment{assignee_id: assignee.id, operation: :auto_assign}
         })
 
@@ -108,24 +108,24 @@ defmodule Diffo.Test.AssignerTest do
     end
 
     test "auto assign two ports to same resource" do
-      {:ok, assignee} = Domain.build_shelf()
+      {:ok, assignee} = Servo.build_shelf()
 
-      {:ok, card} = Domain.build_card(%{})
+      {:ok, card} = Servo.build_card(%{})
 
       updates = [
         card: [family: :ISAM, model: "EBLT48", technology: :adsl2Plus],
         ports: [first: 1, last: 48, free: 48, type: "ADSL2+"]
       ]
 
-      {:ok, card} = Domain.define_card(card, %{characteristic_value_updates: updates})
+      {:ok, card} = Servo.define_card(card, %{characteristic_value_updates: updates})
 
       {:ok, card} =
-        Domain.assign_port(card, %{
+        Servo.assign_port(card, %{
           assignment: %Assignment{assignee_id: assignee.id, operation: :auto_assign}
         })
 
       {:ok, card} =
-        Domain.assign_port(card, %{
+        Servo.assign_port(card, %{
           assignment: %Assignment{assignee_id: assignee.id, operation: :auto_assign}
         })
 
@@ -138,24 +138,24 @@ defmodule Diffo.Test.AssignerTest do
     end
 
     test "specific assignment rejects duplicate request" do
-      {:ok, assignee} = Domain.build_shelf()
+      {:ok, assignee} = Servo.build_shelf()
 
-      {:ok, card} = Domain.build_card(%{})
+      {:ok, card} = Servo.build_card(%{})
 
       updates = [
         card: [family: :ISAM, model: "EBLT48", technology: :adsl2Plus],
         ports: [first: 1, last: 48, free: 48, type: "ADSL2+"]
       ]
 
-      {:ok, card} = Domain.define_card(card, %{characteristic_value_updates: updates})
+      {:ok, card} = Servo.define_card(card, %{characteristic_value_updates: updates})
 
       {:ok, card} =
-        Domain.assign_port(card, %{
+        Servo.assign_port(card, %{
           assignment: %Assignment{id: 5, assignee_id: assignee.id, operation: :assign}
         })
 
       {:error, _error} =
-        Domain.assign_port(card, %{
+        Servo.assign_port(card, %{
           assignment: %Assignment{id: 5, assignee_id: assignee.id, operation: :assign}
         })
 
@@ -168,19 +168,19 @@ defmodule Diffo.Test.AssignerTest do
     end
 
     test "unassign an auto-assigned port from a resource" do
-      {:ok, assignee} = Domain.build_shelf()
+      {:ok, assignee} = Servo.build_shelf()
 
-      {:ok, card} = Domain.build_card(%{})
+      {:ok, card} = Servo.build_card(%{})
 
       updates = [
         card: [family: :ISAM, model: "EBLT48", technology: :adsl2Plus],
         ports: [first: 1, last: 48, free: 48, type: "ADSL2+"]
       ]
 
-      {:ok, card} = Domain.define_card(card, %{characteristic_value_updates: updates})
+      {:ok, card} = Servo.define_card(card, %{characteristic_value_updates: updates})
 
       {:ok, card} =
-        Domain.assign_port(card, %{
+        Servo.assign_port(card, %{
           assignment: %Assignment{assignee_id: assignee.id, operation: :auto_assign}
         })
 
@@ -193,7 +193,7 @@ defmodule Diffo.Test.AssignerTest do
         |> Map.get(:value)
 
       {:ok, card} =
-        Domain.assign_port(card, %{
+        Servo.assign_port(card, %{
           assignment: %Assignment{
             id: assigned_port,
             assignee_id: assignee.id,
diff --git a/test/provider/instance_test.exs b/test/provider/instance_test.exs
index 7733ec8..2e92c93 100644
--- a/test/provider/instance_test.exs
+++ b/test/provider/instance_test.exs
@@ -12,7 +12,7 @@ defmodule Diffo.Provider.InstanceTest do
   end
 
   setup do
-    on_exit(fn ->
+   on_exit(fn ->
       AshNeo4j.Neo4jHelper.delete_all()
     end)
   end
@@ -80,6 +80,10 @@ defmodule Diffo.Provider.InstanceTest do
       refute instance.service_operating_status
       assert instance.specification.id == specification.id
       assert instance.href == "serviceInventoryManagement/v4/service/fibreAccess/#{instance.id}"
+
+      # both specification and instance nodes are labelled :Provider
+      {:ok, response} = AshNeo4j.Neo4jHelper.read_nodes(:Provider)
+      assert length(response.results) == 2
     end
 
     test "create a service instance with a supplied id - success" do
diff --git a/test/provider/specification_test.exs b/test/provider/specification_test.exs
index 44125bb..05f2377 100644
--- a/test/provider/specification_test.exs
+++ b/test/provider/specification_test.exs
@@ -247,7 +247,6 @@ defmodule Diffo.Provider.SpecificationTest do
       assert is_struct(error, Ash.Error.Invalid)
     end
 
-    @tag debug: true
     test "delete specification - failure, related instance" do
       specification = Diffo.Provider.create_specification!(%{name: "bdslAccess"})
       instance = Diffo.Provider.create_instance!(%{specified_by: specification.id})
diff --git a/test/support/resource/card.ex b/test/support/resource/card.ex
index ad043f6..4056a1b 100644
--- a/test/support/resource/card.ex
+++ b/test/support/resource/card.ex
@@ -15,12 +15,12 @@ defmodule Diffo.Test.Card do
   alias Diffo.Provider.Assigner
   alias Diffo.Provider.Assignment
   alias Diffo.Provider.AssignableValue
-  alias Diffo.Test.Domain
+  alias Diffo.Test.Servo
   alias Diffo.Test.CardValue
 
   use Ash.Resource,
     fragments: [BaseInstance],
-    domain: Domain
+    domain: Servo
 
   resource do
     description "An Ash Resource representing a Card"
@@ -58,7 +58,7 @@ defmodule Diffo.Test.Card do
              end)
 
       change after_action(fn changeset, result, _context ->
-               ActionHelper.build_after(changeset, result, Domain, :get_card_by_id)
+               ActionHelper.build_after(changeset, result, Servo, :get_card_by_id)
              end)
 
       change load [:href]
@@ -71,7 +71,7 @@ defmodule Diffo.Test.Card do
 
       change after_action(fn changeset, result, _context ->
                with {:ok, result} <- Characteristic.update_values(result, changeset),
-                    {:ok, result} <- Domain.get_card_by_id(result.id),
+                    {:ok, result} <- Servo.get_card_by_id(result.id),
                     do: {:ok, result}
              end)
     end
@@ -82,7 +82,7 @@ defmodule Diffo.Test.Card do
 
       change after_action(fn changeset, result, _context ->
                with {:ok, result} <- Relationship.relate_instance(result, changeset),
-                    {:ok, result} <- Domain.get_card_by_id(result.id),
+                    {:ok, result} <- Servo.get_card_by_id(result.id),
                     do: {:ok, result}
              end)
     end
@@ -93,7 +93,7 @@ defmodule Diffo.Test.Card do
 
       change after_action(fn changeset, result, _context ->
                with {:ok, result} <- Assigner.assign(result, changeset, :ports, :port),
-                    {:ok, result} <- Domain.get_card_by_id(result.id),
+                    {:ok, result} <- Servo.get_card_by_id(result.id),
                     do: {:ok, result}
              end)
     end
diff --git a/test/support/resource/shelf.ex b/test/support/resource/shelf.ex
index e41a7db..8a48617 100644
--- a/test/support/resource/shelf.ex
+++ b/test/support/resource/shelf.ex
@@ -17,12 +17,12 @@ defmodule Diffo.Test.Shelf do
   alias Diffo.Provider.Assignment
   alias Diffo.Provider.AssignableValue
 
-  alias Diffo.Test.Domain
+  alias Diffo.Test.Servo
   alias Diffo.Test.ShelfValue
 
   use Ash.Resource,
     fragments: [BaseInstance],
-    domain: Domain
+    domain: Servo
 
   resource do
     description "An Ash Resource representing a Shelf"
@@ -60,7 +60,7 @@ defmodule Diffo.Test.Shelf do
              end)
 
       change after_action(fn changeset, result, _context ->
-               ActionHelper.build_after(changeset, result, Domain, :get_shelf_by_id)
+               ActionHelper.build_after(changeset, result, Servo, :get_shelf_by_id)
              end)
 
       change load [:href]
@@ -73,7 +73,7 @@ defmodule Diffo.Test.Shelf do
 
       change after_action(fn changeset, result, _context ->
                with {:ok, result} <- Characteristic.update_values(result, changeset),
-                    {:ok, result} <- Domain.get_shelf_by_id(result.id),
+                    {:ok, result} <- Servo.get_shelf_by_id(result.id),
                     do: {:ok, result}
              end)
     end
@@ -84,7 +84,7 @@ defmodule Diffo.Test.Shelf do
 
       change after_action(fn changeset, result, _context ->
                with {:ok, result} <- Relationship.relate_instance(result, changeset),
-                    {:ok, result} <- Domain.get_shelf_by_id(result.id),
+                    {:ok, result} <- Servo.get_shelf_by_id(result.id),
                     do: {:ok, result}
              end)
     end
@@ -95,7 +95,7 @@ defmodule Diffo.Test.Shelf do
 
       change after_action(fn changeset, result, _context ->
                with {:ok, result} <- Assigner.assign(result, changeset, :slots, :slot),
-                    {:ok, result} <- Domain.get_shelf_by_id(result.id),
+                    {:ok, result} <- Servo.get_shelf_by_id(result.id),
                     do: {:ok, result}
              end)
     end
diff --git a/test/support/domain.ex b/test/support/servo.ex
similarity index 87%
rename from test/support/domain.ex
rename to test/support/servo.ex
index c364ffa..793df85 100644
--- a/test/support/domain.ex
+++ b/test/support/servo.ex
@@ -2,11 +2,11 @@
 #
 # SPDX-License-Identifier: MIT
 
-defmodule Diffo.Test.Domain do
+defmodule Diffo.Test.Servo do
   @moduledoc """
   Diffo - TMF Service and Resource Management with a difference
 
-  Domain - domain for testing
+  Servo - a service and resource management domain
   """
   use Ash.Domain,
     otp_app: :diffo,
@@ -16,7 +16,7 @@ defmodule Diffo.Test.Domain do
   alias Diffo.Test.Card
 
   domain do
-    description "A domain for testing"
+    description "service and resource management"
   end
 
   resources do