diff --git a/lib/polar/machines.ex b/lib/polar/machines.ex
index 303fe5b..1e2ef74 100644
--- a/lib/polar/machines.ex
+++ b/lib/polar/machines.ex
@@ -21,7 +21,7 @@ defmodule Polar.Machines do
 
   alias __MODULE__.Assessment
 
-  defdelegate create_assessment(version, params),
+  defdelegate get_or_create_assessment(version, params),
     to: Assessment.Manager,
-    as: :create
+    as: :get_or_create
 end
diff --git a/lib/polar/machines/assessment.ex b/lib/polar/machines/assessment.ex
index aac62e8..a896bda 100644
--- a/lib/polar/machines/assessment.ex
+++ b/lib/polar/machines/assessment.ex
@@ -17,19 +17,19 @@ defmodule Polar.Machines.Assessment do
   @valid_attrs ~w(
     check_id 
     cluster_id
-    machine_type
+    instance_type
   )a
 
   @required_attrs ~w(
     check_id
     cluster_id
-    machine_type
+    instance_type
   )a
 
   schema "assessments" do
     field :current_state, :string, default: "created"
 
-    field :machine_type, :string
+    field :instance_type, :string
 
     belongs_to :check, Check
     belongs_to :cluster, Cluster
@@ -44,6 +44,6 @@ defmodule Polar.Machines.Assessment do
     assessment
     |> cast(attrs, @valid_attrs)
     |> validate_required(@required_attrs)
-    |> validate_inclusion(:machine_type, ["container", "vm"])
+    |> validate_inclusion(:instance_type, ["container", "vm"])
   end
 end
diff --git a/lib/polar/machines/assessment/manager.ex b/lib/polar/machines/assessment/manager.ex
index 621f840..e46e548 100644
--- a/lib/polar/machines/assessment/manager.ex
+++ b/lib/polar/machines/assessment/manager.ex
@@ -2,6 +2,25 @@ defmodule Polar.Machines.Assessment.Manager do
   alias Polar.Repo
   alias Polar.Machines.Assessment
 
+  def get_or_create(version, params) do
+    check_id = Map.get(params, "check_id") || params.check_id
+    instance_type = Map.get(params, "instance_type") || params.instance_type
+
+    Assessment
+    |> Repo.get_by(
+      version_id: version.id,
+      check_id: check_id,
+      instance_type: instance_type
+    )
+    |> case do
+      %Assessment{} = assessment ->
+        assessment
+
+      nil ->
+        create(version, params)
+    end
+  end
+
   def create(version, params) do
     %Assessment{version_id: version.id}
     |> Assessment.changeset(params)
diff --git a/lib/polar_web/controllers/publish/testing/assessment_controller.ex b/lib/polar_web/controllers/publish/testing/assessment_controller.ex
index 27694e1..2cb4738 100644
--- a/lib/polar_web/controllers/publish/testing/assessment_controller.ex
+++ b/lib/polar_web/controllers/publish/testing/assessment_controller.ex
@@ -11,7 +11,7 @@ defmodule PolarWeb.Publish.Testing.AssessmentController do
         "assessment" => assessment_params
       }) do
     with %Version{} = check <- Repo.get(Version, version_id),
-         {:ok, assessment} <- Machines.create_assessment(check, assessment_params) do
+         {:ok, assessment} <- Machines.get_or_create_assessment(check, assessment_params) do
       assessment = Repo.preload(assessment, [:check])
 
       conn
diff --git a/priv/repo/migrations/20240628092615_add_instance_type_to_assessments.exs b/priv/repo/migrations/20240628092615_add_instance_type_to_assessments.exs
new file mode 100644
index 0000000..dada87b
--- /dev/null
+++ b/priv/repo/migrations/20240628092615_add_instance_type_to_assessments.exs
@@ -0,0 +1,12 @@
+defmodule Polar.Repo.Migrations.AddInstanceTypeToAssessments do
+  use Ecto.Migration
+
+  def change do
+    alter table(:assessments) do
+      add :instance_type, :string, null: false
+    end
+
+    drop index(:assessments, [:check_id, :version_id], unique: true)
+    create index(:assessments, [:check_id, :version_id, :instance_type], unique: true)
+  end
+end
diff --git a/priv/repo/migrations/20240628092615_add_machine_type_to_assessments.exs b/priv/repo/migrations/20240628092615_add_machine_type_to_assessments.exs
deleted file mode 100644
index d6690f2..0000000
--- a/priv/repo/migrations/20240628092615_add_machine_type_to_assessments.exs
+++ /dev/null
@@ -1,12 +0,0 @@
-defmodule Polar.Repo.Migrations.AddMachineTypeToAssessments do
-  use Ecto.Migration
-
-  def change do
-    alter table(:assessments) do
-      add :machine_type, :string, null: false
-    end
-
-    drop index(:assessments, [:check_id, :version_id], unique: true)
-    create index(:assessments, [:check_id, :version_id, :machine_type], unique: true)
-  end
-end
diff --git a/test/polar/machines/assessment/manager_test.exs b/test/polar/machines/assessment/manager_test.exs
index c6f872d..a38ed69 100644
--- a/test/polar/machines/assessment/manager_test.exs
+++ b/test/polar/machines/assessment/manager_test.exs
@@ -45,9 +45,10 @@ defmodule Polar.Machines.Assessment.ManagerTest do
   describe "create assessment" do
     test "successfully create assessment", %{check: check, cluster: cluster, version: version} do
       assert {:ok, assessment} =
-               Machines.create_assessment(version, %{
+               Machines.get_or_create_assessment(version, %{
                  check_id: check.id,
-                 cluster_id: cluster.id
+                 cluster_id: cluster.id,
+                 instance_type: "container"
                })
 
       assert assessment.current_state == "created"
diff --git a/test/polar/machines/assessment/transitions_test.exs b/test/polar/machines/assessment/transitions_test.exs
index 8dc081f..830998f 100644
--- a/test/polar/machines/assessment/transitions_test.exs
+++ b/test/polar/machines/assessment/transitions_test.exs
@@ -43,9 +43,10 @@ defmodule Polar.Machines.Assessment.TransitionsTest do
       Streams.create_version(product, valid_version_attributes(2))
 
     {:ok, assessment} =
-      Machines.create_assessment(version, %{
+      Machines.get_or_create_assessment(version, %{
         check_id: check.id,
-        cluster_id: cluster.id
+        cluster_id: cluster.id,
+        instance_type: "container"
       })
 
     {:ok, assessment: assessment, user: user}
diff --git a/test/polar_web/controllers/publish/event_controller_test.exs b/test/polar_web/controllers/publish/event_controller_test.exs
index 8e1c440..3f17d83 100644
--- a/test/polar_web/controllers/publish/event_controller_test.exs
+++ b/test/polar_web/controllers/publish/event_controller_test.exs
@@ -68,7 +68,11 @@ defmodule PolarWeb.Publish.EventControllerTest do
         })
 
       {:ok, assessment} =
-        Machines.create_assessment(version, %{check_id: check.id, cluster_id: cluster.id})
+        Machines.get_or_create_assessment(version, %{
+          check_id: check.id,
+          cluster_id: cluster.id,
+          instance_type: "container"
+        })
 
       {:ok, assessment: assessment}
     end
diff --git a/test/polar_web/controllers/publish/testing/assessment_controller_test.exs b/test/polar_web/controllers/publish/testing/assessment_controller_test.exs
index eb412a8..cf9b304 100644
--- a/test/polar_web/controllers/publish/testing/assessment_controller_test.exs
+++ b/test/polar_web/controllers/publish/testing/assessment_controller_test.exs
@@ -69,7 +69,8 @@ defmodule PolarWeb.Publish.Testing.AssessmentControllerTest do
         post(conn, ~p"/publish/testing/versions/#{version.id}/assessments", %{
           "assessment" => %{
             "check_id" => check.id,
-            "cluster_id" => cluster.id
+            "cluster_id" => cluster.id,
+            "instance_type" => "container"
           }
         })