diff --git a/e2e-tests/src/tests/scheduling-and-decomposition.test.ts b/e2e-tests/src/tests/scheduling-and-decomposition.test.ts
new file mode 100644
index 0000000000..08339b2e28
--- /dev/null
+++ b/e2e-tests/src/tests/scheduling-and-decomposition.test.ts
@@ -0,0 +1,128 @@
+import { expect, test } from '@playwright/test';
+import req, {awaitScheduling} from '../utilities/requests.js';
+
+test.describe('Scheduling and Decomposing Activities', () => {
+  const plan_start_timestamp = "2021-001T00:00:00.000";
+  const plan_end_timestamp = "2021-090T00:00:00.000";
+  let mission_model_id: number;
+  let plan_id: number;
+  let plan_revision: number;
+  let specification_id: number;
+
+  test.beforeAll(async ({request}) => {
+    let rd = Math.random() * 100000;
+    let jar_id = await req.uploadJarFile(request);
+    // Add Mission Model
+    const model: MissionModelInsertInput = {
+      jar_id,
+      mission: 'aerie_e2e_tests',
+      name: 'Banananation (e2e tests)',
+      version: rd + "",
+    };
+    mission_model_id = await req.createMissionModel(request, model);
+    await delay(1000);
+
+    // Add Plan
+    const plan_input: CreatePlanInput = {
+      model_id: mission_model_id,
+      name: 'test_plan' + rd,
+      start_time: plan_start_timestamp,
+      duration: "24:00:00"
+    };
+    plan_id = await req.createPlan(request, plan_input);
+    plan_revision = await req.getPlanRevision(request, plan_id);
+
+    // Add Scheduling Spec
+    const schedulingSpecification: SchedulingSpecInsertInput = {
+      horizon_end: plan_end_timestamp,
+      horizon_start: plan_start_timestamp,
+      plan_id: plan_id,
+      plan_revision: plan_revision,
+      simulation_arguments: {},
+      analysis_only: false
+    }
+    specification_id = await req.insertSchedulingSpecification(request, schedulingSpecification);
+
+    // Add Goal
+    const schedulingGoal: SchedulingGoalInsertInput =
+        {
+          description: "Cardinality goal",
+          model_id: mission_model_id,
+          name: "my second scheduling goal!" + rd,
+          definition:
+              `export default function cardinalityGoalExample() {
+                        return Goal.CardinalityGoal({
+                            activityTemplate: ActivityTemplates.parent({ label: "unlabeled"}),
+                            specification: { duration: Temporal.Duration.from({ seconds: 10 }) },
+                        });
+                    }`
+        };
+    let goal_id = await req.insertSchedulingGoal(request, schedulingGoal);
+
+    // Assign Scheduling Spec Goal
+    const specGoal: SchedulingSpecGoalInsertInput = {
+      // @ts-ignore
+      goal_id: goal_id,
+      priority: 0,
+      specification_id: specification_id,
+    };
+    await req.createSchedulingSpecGoal(request, specGoal);
+  });
+
+  test.afterAll(async ({request}) => {
+      // Deleting Plan and Model cascades the rest of the cleanup
+      await req.deleteMissionModel(request, mission_model_id);
+      await req.deletePlan(request, plan_id);
+  });
+
+  test('Scheduling Properly assigns Span Ids on Decomposing Activities', async ({request}) => {
+    // Run Scheduling
+    const schedulingResults = await awaitScheduling(request, specification_id);
+    const dataset_id = schedulingResults.datasetId;
+
+    // Check Plan Activities
+    let plan = await req.getPlan(request, plan_id)
+    expect(plan.id).toEqual(plan_id);
+    expect(plan.activity_directives.length).toEqual(1);
+
+    let parentActivity = plan.activity_directives.pop();
+    expect(parentActivity.type).toEqual('parent');
+
+    const simulated_activities = (await req.getSimulationDatasetByDatasetId(request, dataset_id)).simulated_activities
+    expect(simulated_activities.length).toEqual(7) // 1 parent, 2 children, 4 grandchildren
+
+    // Assert Parent Span
+    let parentSpans = simulated_activities.filter(a => a.type === "parent");
+    expect(parentSpans.length).toEqual(1);
+
+    let parentSpan = parentSpans.pop();
+    expect(parentSpan.parent_id).toBeNull();
+    expect(parentSpan.activity_directive.id).toEqual(parentActivity.id)
+
+    // Assert Children Spans
+    let childrenSpans = simulated_activities.filter(a => a.type === "child");
+    expect(childrenSpans.length).toEqual(2);
+    childrenSpans.forEach(a => {
+      expect(a.activity_directive).toBeNull();
+      expect(a.parent_id).not.toBeNull();
+      expect(a.parent_id).toEqual(parentSpan.id);
+    });
+    let child1 = childrenSpans.pop();
+    let child2 = childrenSpans.pop();
+
+    // Assert Grandchildren Spans
+    let grandchildrenSpans = simulated_activities.filter(a => a.type === "grandchild");
+    expect(grandchildrenSpans.length).toEqual(4);
+    grandchildrenSpans.forEach(a => expect(a.activity_directive).toBeNull());
+
+    let gcFirstChild = grandchildrenSpans.filter(a => a.parent_id === child1.id);
+    expect(gcFirstChild.length).toEqual(2);
+
+    let gcSecondChild = grandchildrenSpans.filter(a => a.parent_id === child2.id);
+    expect(gcSecondChild.length).toEqual(2);
+  });
+});
+
+function delay(ms: number) {
+  return new Promise( resolve => setTimeout(resolve, ms) );
+}
diff --git a/e2e-tests/src/types/simulation.d.ts b/e2e-tests/src/types/simulation.d.ts
index f3f9ed6461..0843268feb 100644
--- a/e2e-tests/src/types/simulation.d.ts
+++ b/e2e-tests/src/types/simulation.d.ts
@@ -66,4 +66,7 @@ type SimulatedActivity = {
   duration: string | null;
   start_time: string;
   start_offset: string;
+  type: string;
+  parent_id: number | null;
+  id: number;
 }
diff --git a/e2e-tests/src/utilities/gql.ts b/e2e-tests/src/utilities/gql.ts
index ac8d4288fe..ace3e5c846 100644
--- a/e2e-tests/src/utilities/gql.ts
+++ b/e2e-tests/src/utilities/gql.ts
@@ -169,6 +169,9 @@ const gql = {
           duration
           start_time
           start_offset
+          parent_id
+          type: activity_type_name
+          id
         }
       }
     }
diff --git a/scheduler-server/src/main/java/gov/nasa/jpl/aerie/scheduler/server/services/GraphQLMerlinService.java b/scheduler-server/src/main/java/gov/nasa/jpl/aerie/scheduler/server/services/GraphQLMerlinService.java
index 95cedbad69..58efd0e1ed 100644
--- a/scheduler-server/src/main/java/gov/nasa/jpl/aerie/scheduler/server/services/GraphQLMerlinService.java
+++ b/scheduler-server/src/main/java/gov/nasa/jpl/aerie/scheduler/server/services/GraphQLMerlinService.java
@@ -1654,9 +1654,8 @@ public HashMap<Long, Long> postSpans(final DatasetId datasetId,
     response = postRequest(req, arguments).get();
     final var returnedIds = response.getJsonObject("data").getJsonObject("insert_span").getJsonArray("returning");
     final var simIdToPostgresId = new HashMap<Long, Long>(ids.size());
-    int i = 0;
-    for (final var id : ids) {
-      simIdToPostgresId.put(id, (long) returnedIds.get(i).asJsonObject().getInt("id"));
+    for (int i = 0; i< ids.size(); ++i) {
+      simIdToPostgresId.put(ids.get(i), (long) returnedIds.get(i).asJsonObject().getInt("id"));
     }
     return simIdToPostgresId;
   }