diff --git a/src/resolvers/RouteResolvers.ts b/src/resolvers/RouteResolvers.ts
index 94dc13f..0c71cfd 100644
--- a/src/resolvers/RouteResolvers.ts
+++ b/src/resolvers/RouteResolvers.ts
@@ -7,10 +7,10 @@ export const RouteResolvers: Resolvers<ServerContext> = {
       const shuttles = await contextValue.repository.getShuttlesByRouteId(parent.id);
 
       return shuttles.map(({
-                             coordinates,
-                             name,
-                             id,
-                           }) => ({
+        coordinates,
+        name,
+        id,
+      }) => ({
         coordinates: coordinates as Coordinates,
         name,
         route: parent,
diff --git a/src/resolvers/SystemResolvers.ts b/src/resolvers/SystemResolvers.ts
index b78e922..dbb98ca 100644
--- a/src/resolvers/SystemResolvers.ts
+++ b/src/resolvers/SystemResolvers.ts
@@ -7,23 +7,15 @@ export const SystemResolvers: Resolvers<ServerContext> = {
       return await contextValue.repository.getRoutesBySystemId(parent.id);
     },
     stops: async (parent, args, contextValue, info) => {
-      const stops = await contextValue.repository.getStopsBySystemId(parent.id);
-      return stops.map(({
-                          id,
-                          name,
-                          coordinates
-                        }) => ({
-        id,
-        name,
-        // Both ICoordinates and Coordinates have the same definition
-        coordinates: coordinates as Coordinates,
-      }));
+      return await contextValue.repository.getStopsBySystemId(parent.id);
     },
     stop: async (parent, args, contextValue, info) => {
       if (!args.id) return null;
       const stop = await contextValue.repository.getStopById(args.id);
       if (stop === null) return null;
 
+      if (stop.systemId !== parent.id) return null;
+
       return {
         id: stop.id,
         name: stop.name,
@@ -35,6 +27,8 @@ export const SystemResolvers: Resolvers<ServerContext> = {
       const route = await contextValue.repository.getRouteById(args.id);
       if (route === null) return null;
 
+      if (route.systemId !== parent.id) return null;
+
       return {
         color: route.color,
         id: route.id,
@@ -47,17 +41,12 @@ export const SystemResolvers: Resolvers<ServerContext> = {
       const shuttle = await contextValue.repository.getShuttleById(args.id);
       if (shuttle === null) return null;
 
+      if (shuttle.systemId !== parent.id) return null;
+
       return shuttle;
     },
     shuttles: async (parent, args, contextValue, info) => {
-      const shuttles = await contextValue.repository.getShuttlesBySystemId(parent.id);
-
-      return shuttles.map(shuttle => ({
-        coordinates: shuttle.coordinates,
-        name: shuttle.name,
-        id: shuttle.id,
-        routeId: shuttle.routeId,
-      }));
+      return await contextValue.repository.getShuttlesBySystemId(parent.id);
     }
   },
 }
\ No newline at end of file
diff --git a/test/loaders/ApiBasedRepositoryLoaderTests.test.ts b/test/loaders/ApiBasedRepositoryLoaderTests.test.ts
index 173f696..87cb896 100644
--- a/test/loaders/ApiBasedRepositoryLoaderTests.test.ts
+++ b/test/loaders/ApiBasedRepositoryLoaderTests.test.ts
@@ -7,15 +7,7 @@ import { fetchRouteDataSuccessfulResponse } from "../jsonSnapshots/fetchRouteDat
 import {
   fetchStopAndPolylineDataSuccessfulResponse
 } from "../jsonSnapshots/fetchStopAndPolylineData/fetchStopAndPolylineDataSuccessfulResponse";
-import {
-  generateMockEtas,
-  generateMockOrderedStops,
-  generateMockRoutes,
-  generateMockShuttles,
-  generateMockStops,
-  generateMockSystems
-} from "../generators";
-import { IStop } from "../../src/entities/entities";
+import { generateMockRoutes, generateMockShuttles, generateMockStops, generateMockSystems } from "../testHelpers/mockDataGenerators";
 import {
   fetchShuttleDataSuccessfulResponse
 } from "../jsonSnapshots/fetchShuttleData/fetchShuttleDataSuccessfulResponse";
@@ -24,7 +16,7 @@ import {
   resetGlobalFetchMockJson,
   updateGlobalFetchMockJson,
   updateGlobalFetchMockJsonToThrowSyntaxError
-} from "../mockHelpers/fetchMockHelpers";
+} from "../testHelpers/fetchMockHelpers";
 
 async function assertAsyncCallbackThrowsApiResponseError(callback: () => Promise<any>) {
   await expect(callback).rejects.toThrow(ApiResponseError);
diff --git a/test/loaders/TimedApiBasedRepositoryLoaderTests.test.ts b/test/loaders/TimedApiBasedRepositoryLoaderTests.test.ts
index 18f4616..9979a06 100644
--- a/test/loaders/TimedApiBasedRepositoryLoaderTests.test.ts
+++ b/test/loaders/TimedApiBasedRepositoryLoaderTests.test.ts
@@ -1,6 +1,6 @@
 import { afterEach, beforeAll, beforeEach, describe, expect, it, jest } from "@jest/globals";
 import { TimedApiBasedRepositoryLoader } from "../../src/loaders/TimedApiBasedRepositoryLoader";
-import { resetGlobalFetchMockJson } from "../mockHelpers/fetchMockHelpers";
+import { resetGlobalFetchMockJson } from "../testHelpers/fetchMockHelpers";
 import { UnoptimizedInMemoryRepository } from "../../src/repositories/UnoptimizedInMemoryRepository";
 
 describe("TimedApiBasedRepositoryLoader", () => {
diff --git a/test/repositories/UnoptimizedInMemoryRepositoryTests.test.ts b/test/repositories/UnoptimizedInMemoryRepositoryTests.test.ts
index 906894b..f130ba5 100644
--- a/test/repositories/UnoptimizedInMemoryRepositoryTests.test.ts
+++ b/test/repositories/UnoptimizedInMemoryRepositoryTests.test.ts
@@ -7,7 +7,7 @@ import {
   generateMockShuttles,
   generateMockStops,
   generateMockSystems
-} from "../generators";
+} from "../testHelpers/mockDataGenerators";
 
 // For repositories created in the future, reuse core testing
 // logic from here and differentiate setup (e.g. creating mocks)
diff --git a/test/resolvers/EtaResolverTests.test.ts b/test/resolvers/EtaResolverTests.test.ts
new file mode 100644
index 0000000..73c9770
--- /dev/null
+++ b/test/resolvers/EtaResolverTests.test.ts
@@ -0,0 +1,90 @@
+import { beforeEach, describe, expect, it } from "@jest/globals";
+import { setupTestServerContext } from "../testHelpers/apolloTestServerHelpers";
+import { IEta, IShuttle, IStop, ISystem } from "../../src/entities/entities";
+import {
+  addMockEtaToRepository, addMockShuttleToRepository,
+  addMockStopToRepository,
+  addMockSystemToRepository
+} from "../testHelpers/repositorySetupHelpers";
+import assert = require("node:assert");
+
+describe("EtaResolvers", () => {
+  const context = setupTestServerContext();
+
+  let mockSystem: ISystem;
+  let mockShuttle: IShuttle;
+  let mockStop: IStop;
+  let expectedEta: IEta;
+
+  beforeEach(async () => {
+    mockSystem = await addMockSystemToRepository(context.repository);
+    mockShuttle = await addMockShuttleToRepository(context.repository, mockSystem.id);
+    mockStop = await addMockStopToRepository(context.repository, mockSystem.id);
+    expectedEta = await addMockEtaToRepository(context.repository, mockStop.id, mockShuttle.id);
+  });
+
+  async function getResponseForEtaQuery(query: string) {
+    const response = await context.testServer.executeOperation({
+      query,
+      variables: {
+        systemId: mockSystem.id,
+        shuttleId: mockShuttle.id,
+      },
+    }, {
+      contextValue: {
+        repository: context.repository,
+      }
+    });
+    return response;
+  }
+
+  describe("stop", () => {
+    const query = `
+    query GetETAStop($systemId: ID!, $shuttleId: ID!) {
+      system(id: $systemId) {
+        shuttle(id: $shuttleId) {
+          etas {
+            stop {
+              id
+            }
+          }
+        }
+      }
+    }
+    `;
+
+    it("returns the associated stop if it exists", async () => {
+      const response = await getResponseForEtaQuery(query);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      const eta = (response.body.singleResult.data?.system as any).shuttle.etas[0];
+      expect(eta.stop.id).toEqual(expectedEta.stopId);
+    });
+  });
+
+  describe("shuttle", () => {
+    const query = `
+    query GetETAShuttle($systemId: ID!, $shuttleId: ID!) {
+      system(id: $systemId) {
+        shuttle(id: $shuttleId) {
+          etas {
+            shuttle {
+              id
+            }
+          }
+        }
+      }
+    }
+    `;
+
+    it("returns the associated shuttle if it exists", async () => {
+      const response = await getResponseForEtaQuery(query);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      const eta = (response.body.singleResult.data?.system as any).shuttle.etas[0];
+      expect(eta.shuttle.id).toEqual(expectedEta.shuttleId);
+    });
+  });
+});
\ No newline at end of file
diff --git a/test/resolvers/OrderedStopResolverTests.test.ts b/test/resolvers/OrderedStopResolverTests.test.ts
new file mode 100644
index 0000000..11c46e4
--- /dev/null
+++ b/test/resolvers/OrderedStopResolverTests.test.ts
@@ -0,0 +1,288 @@
+import { beforeEach, describe, expect, it } from "@jest/globals";
+import { setupTestServerContext } from "../testHelpers/apolloTestServerHelpers";
+import { IRoute, IStop, ISystem } from "../../src/entities/entities";
+import { generateMockOrderedStops, generateMockStops } from "../testHelpers/mockDataGenerators";
+import { addMockRouteToRepository, addMockSystemToRepository } from "../testHelpers/repositorySetupHelpers";
+import assert = require("node:assert");
+
+describe("OrderedStopResolvers", () => {
+  const context = setupTestServerContext();
+
+  let mockSystem: ISystem;
+  let mockRoute: IRoute;
+  let mockStops: IStop[];
+
+  beforeEach(async () => {
+    mockSystem = await addMockSystemToRepository(context.repository);
+    mockRoute = await addMockRouteToRepository(context.repository, mockSystem.id);
+
+    mockStops = generateMockStops();
+    await Promise.all(mockStops.map(async (mockStop) => {
+      mockStop.systemId = mockSystem.id;
+      await context.repository.addOrUpdateStop(mockStop);
+    }));
+  });
+
+  async function setUpOrderedStopsInRepository() {
+    const orderedStops = generateMockOrderedStops();
+
+    // Set up IDs and link stops together to work with the test query
+    orderedStops[0].routeId = mockRoute.id;
+    orderedStops[1].routeId = mockRoute.id;
+
+    // Ensure that there is no duplication
+    orderedStops[0].stopId = mockStops[0].id;
+    orderedStops[1].stopId = mockStops[1].id;
+
+    // Link the stops together
+    orderedStops[0].nextStop = orderedStops[1];
+    orderedStops[1].previousStop = orderedStops[0];
+    await context.repository.addOrUpdateOrderedStop(orderedStops[0]);
+    await context.repository.addOrUpdateOrderedStop(orderedStops[1]);
+    return orderedStops;
+  }
+
+  describe("nextStop", () => {
+    async function getResponseForNextStopQuery(stopId: string) {
+      const query = `
+      query GetNextStop($systemId: ID!, $routeId: ID!, $stopId: ID!) {
+        system(id: $systemId) {
+          route(id: $routeId) {
+            orderedStop(forStopId: $stopId) {
+              nextStop {
+                routeId
+                stopId
+              }
+            }
+          }
+        }
+      }
+      `;
+
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          routeId: mockRoute.id,
+          stopId,
+        },
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+
+    it("returns the next stop if it exists", async () => {
+      // Arrange
+      const orderedStops = await setUpOrderedStopsInRepository();
+
+      // Act
+      const response = await getResponseForNextStopQuery(orderedStops[0].stopId);
+
+      // Assert
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const nextStop = (response.body.singleResult.data?.system as any).route.orderedStop.nextStop;
+      expect(nextStop.stopId).toEqual(orderedStops[1].stopId);
+      expect(nextStop.routeId).toEqual(orderedStops[1].routeId);
+    });
+
+    it("returns null if there is no next stop in the repository", async () => {
+      const orderedStops = await setUpOrderedStopsInRepository();
+      orderedStops[0].nextStop = undefined;
+      await context.repository.addOrUpdateOrderedStop(orderedStops[0]);
+
+      const response = await getResponseForNextStopQuery(orderedStops[0].stopId);
+
+      assert(response.body.kind === "single");
+      const nonexistentNextStop = (response.body.singleResult.data?.system as any).route.orderedStop.nextStop;
+      expect(nonexistentNextStop).toBeNull();
+    });
+
+    it("returns null if the next stop object no longer exists", async () => {
+      const orderedStops = await setUpOrderedStopsInRepository();
+      await context.repository.removeStopIfExists(orderedStops[1].stopId);
+
+      const response = await getResponseForNextStopQuery(orderedStops[0].stopId);
+
+      assert(response.body.kind === "single");
+      const nonexistentNextStop = (response.body.singleResult.data?.system as any).route.orderedStop.nextStop;
+      expect(nonexistentNextStop).toBeNull();
+    });
+  });
+
+  describe("previousStop", () => {
+    async function getResponseForPreviousStopQuery(stopId: string) {
+      const query = `
+        query GetNextStop($systemId: ID!, $routeId: ID!, $stopId: ID!) {
+          system(id: $systemId) {
+            route(id: $routeId) {
+              orderedStop(forStopId: $stopId) {
+                previousStop {
+                  routeId
+                  stopId
+                }
+              }
+            }
+          }
+        }
+      `;
+
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          routeId: mockRoute.id,
+          stopId,
+        },
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+    it("returns the previous stop if it exists", async () => {
+      // Arrange
+      const orderedStops = await setUpOrderedStopsInRepository();
+
+      // Act
+      const response = await getResponseForPreviousStopQuery(orderedStops[1].stopId);
+
+      // Assert
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const previousStop = (response.body.singleResult.data?.system as any).route.orderedStop.previousStop;
+      expect(previousStop.stopId).toEqual(orderedStops[0].stopId);
+      expect(previousStop.routeId).toEqual(orderedStops[0].routeId);
+    });
+
+    it("returns null if there is no previous stop in the repository", async () => {
+      const orderedStops = await setUpOrderedStopsInRepository();
+      orderedStops[1].previousStop = undefined;
+      await context.repository.addOrUpdateOrderedStop(orderedStops[1]);
+
+      const response = await getResponseForPreviousStopQuery(orderedStops[1].stopId);
+
+      assert(response.body.kind === "single");
+      const nonexistentPreviousStop = (response.body.singleResult.data?.system as any).route.orderedStop.previousStop;
+      expect(nonexistentPreviousStop).toBeNull();
+    });
+
+    it("returns null if the current stop no longer exists", async () => {
+      const orderedStops = await setUpOrderedStopsInRepository();
+      await context.repository.removeStopIfExists(orderedStops[0].stopId);
+
+      const response = await getResponseForPreviousStopQuery(orderedStops[1].stopId);
+
+      assert(response.body.kind === "single");
+      const nonexistentPreviousStop = (response.body.singleResult.data?.system as any).route.orderedStop.previousStop;
+      expect(nonexistentPreviousStop).toBeNull();
+    });
+  });
+
+  describe("route", () => {
+    // Note that there is no `orderedStop(forRouteId)` resolver,
+    // so fetch all ordered stops for a stop instead.
+    // If we went through the route ID, it would've
+    // relied on the parent data within the route.orderedStop resolver
+    async function getResponseForRouteQuery(stopId: string) {
+      const query = `
+      query GetNextStop($systemId: ID!, $stopId: ID!) {
+        system(id: $systemId) {
+          stop(id: $stopId) {
+            orderedStops {
+              route {
+                id
+                name
+              }
+            }
+          }
+        }
+      }
+      `;
+
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          stopId,
+        }
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+    it("returns the associated route if it exists", async () => {
+      const orderedStops = generateMockOrderedStops();
+      orderedStops[0].routeId = mockRoute.id;
+      orderedStops[0].stopId = mockStops[0].id;
+
+      // Add one stop only
+      await context.repository.addOrUpdateOrderedStop(orderedStops[0]);
+
+      const response = await getResponseForRouteQuery(orderedStops[1].stopId);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      const route = (response.body.singleResult.data?.system as any).stop.orderedStops[0].route
+
+      expect(route.id).toEqual(mockRoute.id);
+      expect(route.name).toEqual(mockRoute.name);
+    });
+
+  });
+
+  describe("stop", () => {
+    async function getResponseForStopQuery(stopId: string) {
+      const query = `
+      query GetNextStop($systemId: ID!, $routeId: ID!, $stopId: ID!) {
+        system(id: $systemId) {
+          route(id: $routeId) {
+            orderedStop(forStopId: $stopId) {
+              stop {
+                name
+                id
+              }
+            }
+          }
+        }
+      }
+      `;
+
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          routeId: mockRoute.id,
+          stopId,
+        }
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+    it("returns the associated stop if it exists", async () => {
+      const orderedStops = await setUpOrderedStopsInRepository();
+      orderedStops[0].stopId = mockStops[0].id;
+      await context.repository.addOrUpdateOrderedStop(orderedStops[0]);
+
+      const response = await getResponseForStopQuery(orderedStops[0].stopId);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      const stop = (response.body.singleResult.data?.system as any).route.orderedStop.stop;
+      expect(stop.name).toEqual(mockStops[0].name);
+      expect(stop.id).toEqual(mockStops[0].id);
+    });
+  });
+});
+
diff --git a/test/resolvers/QueryResolverTests.test.ts b/test/resolvers/QueryResolverTests.test.ts
new file mode 100644
index 0000000..73f8e83
--- /dev/null
+++ b/test/resolvers/QueryResolverTests.test.ts
@@ -0,0 +1,95 @@
+import { describe, expect, it } from "@jest/globals";
+import { generateMockSystems } from "../testHelpers/mockDataGenerators";
+import { setupTestServerContext } from "../testHelpers/apolloTestServerHelpers";
+import assert = require("node:assert");
+
+// See Apollo documentation for integration test guide
+// https://www.apollographql.com/docs/apollo-server/testing/testing
+
+describe("QueryResolvers", () => {
+  const context = setupTestServerContext();
+
+  async function addMockSystems() {
+    const systems = generateMockSystems();
+    await Promise.all(systems.map(async (system) => {
+      await context.repository.addOrUpdateSystem(system);
+    }));
+    return systems;
+  }
+
+  describe("systems", () => {
+    it("returns systems from the repository", async () => {
+      const systems = await addMockSystems();
+
+      const query = `
+      query GetSystems
+      {
+        systems {
+          name
+        }
+      }
+      `;
+
+      const response = await context.testServer.executeOperation({
+        query,
+      }, {
+        contextValue: {
+          repository: context.repository,
+        },
+      });
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      expect(response.body.singleResult.data?.systems).toHaveLength(systems.length);
+    });
+  });
+
+  describe("system", () => {
+    const query = `
+    query GetSystem($id: ID!)
+    {
+      system(id: $id) {
+        name
+      }
+    }
+    `;
+
+    it("returns a system for an ID from the repository", async () => {
+      const systems = await addMockSystems();
+      const systemToGet = systems[1];
+
+      const response = await context.testServer.executeOperation({
+        query,
+        variables: {
+          id: systemToGet.id,
+        }
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect(response.body.singleResult.data?.system).toBeDefined();
+    });
+
+    it("returns null if there is no system", async () => {
+      const response = await context.testServer.executeOperation({
+        query,
+        variables: {
+          id: "nonexistent-id",
+        }
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect(response.body.singleResult.data?.system).toBeNull();
+    });
+  });
+});
\ No newline at end of file
diff --git a/test/resolvers/RouteResolverTests.test.ts b/test/resolvers/RouteResolverTests.test.ts
new file mode 100644
index 0000000..ba5b403
--- /dev/null
+++ b/test/resolvers/RouteResolverTests.test.ts
@@ -0,0 +1,148 @@
+import { beforeEach, describe, expect, it } from "@jest/globals";
+import { setupTestServerContext } from "../testHelpers/apolloTestServerHelpers";
+import {
+  addMockRouteToRepository,
+  addMockStopToRepository,
+  addMockSystemToRepository
+} from "../testHelpers/repositorySetupHelpers";
+import { generateMockOrderedStops, generateMockShuttles } from "../testHelpers/mockDataGenerators";
+import { IRoute, IStop, ISystem } from "../../src/entities/entities";
+import assert = require("node:assert");
+
+describe("RouteResolvers", () => {
+  const context = setupTestServerContext();
+
+  let mockSystem: ISystem;
+  let mockRoute: IRoute;
+  let mockStop: IStop;
+
+  beforeEach(async () => {
+    mockSystem = await addMockSystemToRepository(context.repository);
+    const systemId = mockSystem.id;
+
+    mockRoute = await addMockRouteToRepository(context.repository, systemId);
+    mockStop = await addMockStopToRepository(context.repository, systemId);
+  });
+
+
+  describe("shuttles", () => {
+    async function getResponseForShuttlesQuery() {
+      const query = `
+      query GetRouteShuttles($systemId: ID!, $routeId: ID!) {
+        system(id: $systemId) {
+          route(id: $routeId) {
+            shuttles {
+              id
+              name
+            }
+          }
+        }
+      }
+      `;
+
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          routeId: mockRoute.id,
+        },
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+    it("returns shuttle array if there are shuttles", async () => {
+      const expectedShuttles = generateMockShuttles();
+      const expectedShuttle = expectedShuttles[0];
+      expectedShuttle.systemId = mockSystem.id;
+      expectedShuttle.routeId = mockRoute.id;
+      await context.repository.addOrUpdateShuttle(expectedShuttle);
+
+      const response = await getResponseForShuttlesQuery();
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined()
+      const shuttle = (response.body.singleResult.data as
+        any).system.route.shuttles[0];
+      expect(shuttle.id).toEqual(expectedShuttle.id);
+      expect(shuttle.name).toEqual(expectedShuttle.name);
+    });
+
+    it("returns empty array if there are no shuttles", async () => {
+      const response = await getResponseForShuttlesQuery();
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined()
+      const shuttles = (response.body.singleResult.data as
+        any).system.route.shuttles;
+      expect(shuttles.length).toEqual(0);
+    });
+  });
+
+  describe("orderedStop", () => {
+    async function getResponseForOrderedStopQuery() {
+      const query = `
+      query GetRouteOrderedStop($systemId: ID!, $routeId: ID!, $stopId: ID!) {
+        system(id: $systemId) {
+          route(id: $routeId) {
+            orderedStop(forStopId: $stopId) {
+              stopId
+            }
+          }
+        }
+      }
+      `;
+
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          routeId: mockRoute.id,
+          stopId: mockStop.id,
+        }
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+    it("returns ordered stop using provided data", async () => {
+      const orderedStops = generateMockOrderedStops();
+      const expectedOrderedStop = orderedStops[0];
+      expectedOrderedStop.stopId = mockStop.id;
+      expectedOrderedStop.routeId = mockRoute.id;
+      await context.repository.addOrUpdateOrderedStop(expectedOrderedStop);
+
+      const response = await getResponseForOrderedStopQuery();
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const orderedStop = (response.body.singleResult.data as
+        any).system.route.orderedStop;
+      expect(orderedStop.stopId).toEqual(expectedOrderedStop.stopId);
+    });
+
+    it("returns null if the stop doesn't exist", async () => {
+      const orderedStops = generateMockOrderedStops();
+      const expectedOrderedStop = orderedStops[0];
+      expectedOrderedStop.stopId = mockStop.id;
+      expectedOrderedStop.routeId = mockRoute.id;
+      await context.repository.addOrUpdateOrderedStop(expectedOrderedStop);
+
+      await context.repository.removeStopIfExists(mockStop.id);
+
+      const response = await getResponseForOrderedStopQuery();
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const orderedStop = (response.body.singleResult.data as
+        any).system.route.orderedStop;
+      expect(orderedStop).toBeNull();
+    });
+  });
+});
\ No newline at end of file
diff --git a/test/resolvers/ShuttleResolverTests.test.ts b/test/resolvers/ShuttleResolverTests.test.ts
new file mode 100644
index 0000000..0811c3b
--- /dev/null
+++ b/test/resolvers/ShuttleResolverTests.test.ts
@@ -0,0 +1,200 @@
+import { beforeEach, describe, expect, it } from "@jest/globals";
+import { generateMockEtas, generateMockRoutes } from "../testHelpers/mockDataGenerators";
+import { IShuttle, ISystem } from "../../src/entities/entities";
+import { setupTestServerContext } from "../testHelpers/apolloTestServerHelpers";
+import { addMockShuttleToRepository, addMockSystemToRepository } from "../testHelpers/repositorySetupHelpers";
+import assert = require("node:assert");
+
+
+describe("ShuttleResolvers", () => {
+  const context = setupTestServerContext();
+
+  let mockSystem: ISystem;
+  let mockShuttle: IShuttle;
+
+  beforeEach(async () => {
+    mockSystem = await addMockSystemToRepository(context.repository);
+    mockShuttle = await addMockShuttleToRepository(context.repository,
+      mockSystem.id);
+  });
+
+
+  async function addMockEtas(shuttleId: string) {
+    const etas = generateMockEtas();
+    await Promise.all(etas.map(async (eta) => {
+      eta.shuttleId = shuttleId;
+      await context.repository.addOrUpdateEta(eta);
+    }));
+    return etas;
+  }
+
+  describe("eta", () => {
+    const query = `
+    query GetShuttleETAs($systemId: ID!, $shuttleId: ID!, $stopId: ID!)
+    {
+      system(id: $systemId) {
+        shuttle(id: $shuttleId) {
+          eta(forStopId: $stopId) {
+            secondsRemaining
+          }
+        }
+      }
+    }
+    `
+    it("returns ETA data for stop ID if exists", async () => {
+      const etas = await addMockEtas(mockShuttle.id);
+
+      const mockEta = etas[1];
+
+      // Act
+      const response = await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          shuttleId: mockShuttle.id,
+          stopId: mockEta.stopId,
+        },
+      }, {
+        contextValue: {
+          repository: context.repository,
+        },
+      });
+
+      // Assert
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as
+        any).system.shuttle.eta.secondsRemaining).toEqual(mockEta.secondsRemaining);
+    });
+
+    it("returns null if it doesn't exist", async () => {
+      const response = await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          shuttleId: mockShuttle.id,
+          stopId: "nonexistent-stop",
+        }
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+
+      // Assert
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as
+        any).system.shuttle.eta).toBeNull();
+    });
+  });
+
+  describe("etas", () => {
+    const query = `
+    query GetShuttleETAs($systemId: ID!, $shuttleId: ID!)
+    {
+      system(id: $systemId) {
+        shuttle(id: $shuttleId) {
+          etas {
+            secondsRemaining
+          }
+        }
+      }
+    }
+    `
+
+    it("returns associated ETAs if they exist for the shuttle", async () => {
+      const etas = await addMockEtas(mockShuttle.id);
+
+      const response = await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          shuttleId: mockShuttle.id,
+        },
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as
+        any).system.shuttle.etas).toHaveLength(etas.length);
+    });
+
+    it("returns empty array if no ETAs exist", async () => {
+      const response = await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          shuttleId: mockShuttle.id,
+        },
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as
+        any).system.shuttle.etas).toHaveLength(0);
+
+    });
+  });
+  describe("route", () => {
+    const query = `
+    query GetShuttleRoute($systemId: ID!, $shuttleId: ID!) {
+      system(id: $systemId) {
+        shuttle(id: $shuttleId) {
+          route {
+             color
+             id
+             name
+             polylineCoordinates {
+               latitude
+               longitude
+             }
+          }
+        }
+      }
+    }
+    `
+
+    async function getResponseForQuery() {
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          shuttleId: mockShuttle.id,
+        }
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+    it("returns the route if it exists", async () => {
+      const mockRoute = generateMockRoutes()[0];
+      await context.repository.addOrUpdateRoute(mockRoute);
+
+      const response = await getResponseForQuery();
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as any).system.shuttle.route.id).toEqual(mockRoute.id);
+    });
+
+    it("returns null if there is no route", async () => {
+      const response = await getResponseForQuery();
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as any).system.shuttle.route).toBeNull();
+    });
+
+  });
+});
\ No newline at end of file
diff --git a/test/resolvers/StopResolverTests.test.ts b/test/resolvers/StopResolverTests.test.ts
new file mode 100644
index 0000000..2a044b1
--- /dev/null
+++ b/test/resolvers/StopResolverTests.test.ts
@@ -0,0 +1,108 @@
+import { beforeEach, describe, expect, it } from "@jest/globals";
+import { setupTestServerContext } from "../testHelpers/apolloTestServerHelpers";
+import { generateMockEtas, generateMockOrderedStops } from "../testHelpers/mockDataGenerators";
+import { IStop, ISystem } from "../../src/entities/entities";
+import { addMockStopToRepository, addMockSystemToRepository } from "../testHelpers/repositorySetupHelpers";
+import assert = require("node:assert");
+
+describe("StopResolvers", () => {
+  const context = setupTestServerContext();
+
+  let mockStop: IStop;
+  let mockSystem: ISystem;
+
+  beforeEach(async () => {
+    mockSystem = await addMockSystemToRepository(context.repository);
+    mockStop = await addMockStopToRepository(context.repository, mockSystem.id);
+  })
+
+  async function getResponseForQuery(query: string) {
+    return await context.testServer.executeOperation({
+      query,
+      variables: {
+        systemId: mockSystem.id,
+        stopId: mockStop.id,
+      },
+    }, {
+      contextValue: {
+        repository: context.repository,
+      }
+    });
+  }
+
+  describe("orderedStops", () => {
+    const query = `
+    query GetOrderedStops($systemId: ID!, $stopId: ID!) {
+      system(id: $systemId) {
+        stop(id: $stopId) {
+          orderedStops {
+            routeId
+            stopId
+          }
+        }
+      }
+    }
+    `
+
+
+    it("returns ordered stops if they exist for the stop ID", async () => {
+      let mockOrderedStops = generateMockOrderedStops();
+      mockOrderedStops = mockOrderedStops.filter((orderedStop) => orderedStop.stopId === mockOrderedStops[0].stopId);
+      await Promise.all(mockOrderedStops.map(async orderedStop => {
+        orderedStop.stopId = mockStop.id;
+        await context.repository.addOrUpdateOrderedStop(orderedStop);
+      }));
+
+      const response = await getResponseForQuery(query);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as any).system.stop.orderedStops).toHaveLength(mockOrderedStops.length);
+    });
+
+    it("returns empty array if no ordered stops exist", async () => {
+      const response = await getResponseForQuery(query);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as any).system.stop.orderedStops).toHaveLength(0);
+    });
+  });
+
+  describe("etas", () => {
+    const query = `
+    query GetEtas($systemId: ID!, $stopId: ID!) {
+      system(id: $systemId) {
+        stop(id: $stopId) {
+          etas {
+            secondsRemaining
+          }
+        }
+      }
+    }
+    `
+
+    it("returns ETAs if they exist for the stop ID", async () => {
+      let mockEtas = generateMockEtas();
+      mockEtas = mockEtas.filter((eta) => eta.stopId === mockEtas[0].stopId);
+      await Promise.all(mockEtas.map(async eta => {
+        eta.stopId = mockStop.id;
+        await context.repository.addOrUpdateEta(eta);
+      }));
+
+      const response = await getResponseForQuery(query);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as any).system.stop.etas).toHaveLength(mockEtas.length);
+    });
+
+    it("returns empty array if no ETAs exist", async () => {
+      const response = await getResponseForQuery(query);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      expect((response.body.singleResult.data as any).system.stop.etas).toHaveLength(0);
+    });
+  });
+});
\ No newline at end of file
diff --git a/test/resolvers/SystemResolverTests.test.ts b/test/resolvers/SystemResolverTests.test.ts
new file mode 100644
index 0000000..7020075
--- /dev/null
+++ b/test/resolvers/SystemResolverTests.test.ts
@@ -0,0 +1,321 @@
+import { beforeEach, describe, expect, it } from "@jest/globals";
+import { setupTestServerContext } from "../testHelpers/apolloTestServerHelpers";
+import { generateMockRoutes, generateMockShuttles, generateMockStops } from "../testHelpers/mockDataGenerators";
+import {
+  addMockRouteToRepository,
+  addMockShuttleToRepository,
+  addMockStopToRepository,
+  addMockSystemToRepository
+} from "../testHelpers/repositorySetupHelpers";
+import { ISystem } from "../../src/entities/entities";
+import assert = require("node:assert");
+
+describe("SystemResolvers", () => {
+  const context = setupTestServerContext();
+
+  let mockSystem: ISystem;
+
+  beforeEach(async () => {
+    mockSystem = await addMockSystemToRepository(context.repository);
+  });
+
+  // TODO: Consolidate these into one single method taking an object
+  async function getResponseFromQueryNeedingSystemId(query: string) {
+    return await context.testServer.executeOperation({
+      query,
+      variables: {
+        systemId: mockSystem.id,
+      },
+    }, {
+      contextValue: {
+        repository: context.repository
+      },
+    });
+  }
+
+  describe("routes", () => {
+    const query = `
+    query GetSystemRoutes($systemId: ID!) {
+      system(id: $systemId) {
+        routes {
+          id
+          name
+        }
+      }
+    }
+    `;
+
+    it("gets routes associated with system id", async () => {
+      const expectedRoutes = generateMockRoutes();
+      await Promise.all(expectedRoutes.map(async (route) => {
+        route.systemId = mockSystem.id;
+        await context.repository.addOrUpdateRoute(route);
+      }));
+
+      const response = await getResponseFromQueryNeedingSystemId(query);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined()
+      const routes = (response.body.singleResult.data as any).system.routes;
+      expect(routes.length === expectedRoutes.length);
+    });
+  });
+
+  describe("stops", () => {
+    const query = `
+    query GetSystemStops($systemId: ID!) {
+      system(id: $systemId) {
+        stops {
+          id
+          name
+        }
+      }
+    }
+    `;
+
+    it("gets stops associated with system id", async () => {
+      const expectedStops = generateMockStops();
+      await Promise.all(expectedStops.map(async (stop) => {
+        stop.systemId = mockSystem.id;
+        await context.repository.addOrUpdateStop(stop);
+      }));
+
+      const response = await getResponseFromQueryNeedingSystemId(query);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined()
+      const stops = (response.body.singleResult.data as any).system.stops;
+      expect(stops.length === expectedStops.length);
+    });
+  });
+
+  describe("stop", () => {
+    async function getResponseForStopQuery(stopId: string) {
+      const query = `
+      query GetSystemStop($systemId: ID!, $stopId: ID!) {
+        system(id: $systemId) {
+          stop(id: $stopId) {
+            id
+            name
+          }
+        }
+      }
+      `;
+
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          stopId: stopId,
+        },
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+    it("gets the stop with the correct id", async () => {
+      const mockStop = await addMockStopToRepository(context.repository, mockSystem.id);
+
+      const response = await getResponseForStopQuery(mockStop.id);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      const stop = (response.body.singleResult.data as any).system.stop;
+      expect(stop.id).toEqual(mockStop.id);
+      expect(stop.name).toEqual(mockStop.name);
+    });
+
+    it("returns null if the stop isn't associated with the system", async () => {
+      const updatedSystem = {
+        ...mockSystem,
+        id: "2",
+      }
+      await context.repository.addOrUpdateSystem(updatedSystem);
+
+      const mockStop = await addMockStopToRepository(context.repository, updatedSystem.id);
+
+      const response = await getResponseForStopQuery(mockStop.id);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const stop = (response.body.singleResult.data as any).system.stop;
+      expect(stop).toBeNull();
+    });
+
+    it("returns null if there is no stop", async () => {
+      const response = await getResponseForStopQuery("1");
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const stop = (response.body.singleResult.data as any).system.stop;
+      expect(stop).toBeNull();
+    });
+  });
+
+  describe("route", () => {
+    async function getResponseForRouteQuery(routeId: string) {
+      const query = `
+      query GetSystemRoute($systemId: ID!, $routeId: ID!) {
+        system(id: $systemId) {
+          route(id: $routeId) {
+            id
+            name
+          }
+        }
+      }
+      `;
+
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          routeId,
+        },
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+    it("gets the route with the correct id", async () => {
+      const mockRoute = await addMockRouteToRepository(context.repository, mockSystem.id);
+
+      const response = await getResponseForRouteQuery(mockRoute.id);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const route = (response.body.singleResult.data as any).system.route;
+      expect(route.id).toEqual(mockRoute.id);
+      expect(route.name).toEqual(mockRoute.name);
+    });
+
+    it("returns null if the route isn't associated with the system", async () => {
+      const updatedSystem = {
+        ...mockSystem,
+        id: "2",
+      }
+      await context.repository.addOrUpdateSystem(updatedSystem);
+
+      const mockRoute = await addMockRouteToRepository(context.repository, updatedSystem.id);
+
+      const response = await getResponseForRouteQuery(mockRoute.id);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const route = (response.body.singleResult.data as any).system.route;
+      expect(route).toBeNull();
+    });
+
+    it("returns null if there is no route", async () => {
+      const response = await getResponseForRouteQuery("nonexistent-route-id");
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const route = (response.body.singleResult.data as any).system.route;
+      expect(route).toBeNull();
+    });
+  });
+
+  describe("shuttle", () => {
+    async function getResponseForShuttleQuery(shuttleId: string) {
+      const query = `
+      query GetSystemShuttle($systemId: ID!, $shuttleId: ID!) {
+        system(id: $systemId) {
+          shuttle(id: $shuttleId) {
+            id
+            name
+          }
+        }
+      }
+      `;
+
+      return await context.testServer.executeOperation({
+        query,
+        variables: {
+          systemId: mockSystem.id,
+          shuttleId: shuttleId,
+        }
+      }, {
+        contextValue: {
+          repository: context.repository,
+        }
+      });
+    }
+
+    it("gets the shuttle with the correct id", async () => {
+      const mockShuttle = await addMockShuttleToRepository(context.repository, mockSystem.id);
+
+      const response = await getResponseForShuttleQuery(mockShuttle.id);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+      const shuttle = (response.body.singleResult.data as any).system.shuttle;
+      expect(shuttle.id).toEqual(mockShuttle.id);
+      expect(shuttle.name).toEqual(mockShuttle.name);
+    });
+
+    it("returns null if the shuttle isn't associated with the system", async () => {
+      const updatedSystem = {
+        ...mockSystem,
+        id: "2",
+      }
+      await context.repository.addOrUpdateSystem(updatedSystem);
+
+      const mockShuttle = await addMockShuttleToRepository(context.repository, updatedSystem.id);
+
+      const response = await getResponseForShuttleQuery(mockShuttle.id);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const shuttle = (response.body.singleResult.data as any).system.shuttle;
+      expect(shuttle).toBeNull();
+    });
+
+    it("returns null if there is no shuttle", async () => {
+      const response = await getResponseForShuttleQuery("nonexistent-shuttle-id");
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined();
+
+      const shuttle = (response.body.singleResult.data as any).system.shuttle;
+      expect(shuttle).toBeNull();
+    });
+  });
+
+  describe("shuttles", () => {
+    const query = `
+    query GetSystemShuttle($systemId: ID!) {
+      system(id: $systemId) {
+        shuttles {
+          id
+          name
+        }
+      }
+    }
+    `;
+
+    it("gets shuttles associated with system id", async () => {
+      const expectedShuttles = generateMockShuttles();
+      await Promise.all(expectedShuttles.map(async (shuttle) => {
+        shuttle.systemId = mockSystem.id;
+        await context.repository.addOrUpdateShuttle(shuttle);
+      }));
+
+      const response = await getResponseFromQueryNeedingSystemId(query);
+
+      assert(response.body.kind === "single");
+      expect(response.body.singleResult.errors).toBeUndefined()
+      const shuttles = (response.body.singleResult.data as any).system.shuttles;
+      expect(shuttles.length === expectedShuttles.length);
+    });
+  });
+});
\ No newline at end of file
diff --git a/test/testHelpers/apolloTestServerHelpers.ts b/test/testHelpers/apolloTestServerHelpers.ts
new file mode 100644
index 0000000..78b322f
--- /dev/null
+++ b/test/testHelpers/apolloTestServerHelpers.ts
@@ -0,0 +1,30 @@
+import { readFileSync } from "fs";
+import { ApolloServer } from "@apollo/server";
+import { MergedResolvers } from "../../src/MergedResolvers";
+import { UnoptimizedInMemoryRepository } from "../../src/repositories/UnoptimizedInMemoryRepository";
+import { beforeEach } from "@jest/globals";
+import { ServerContext } from "../../src/ServerContext";
+
+
+function setUpTestServer() {
+  // Leaving this separate from the main server in case
+  // configuration changes
+  const typeDefs = readFileSync("./schema.graphqls", "utf8");
+  return new ApolloServer({
+    typeDefs,
+    resolvers: MergedResolvers,
+  });
+}
+
+export function setupTestServerContext() {
+  // @ts-ignore
+  const context: { testServer: ApolloServer<ServerContext>; repository: UnoptimizedInMemoryRepository } = {};
+
+  beforeEach(() => {
+    context.testServer = setUpTestServer();
+    context.repository = new UnoptimizedInMemoryRepository();
+  });
+
+  // Return a reference, not destructured values
+  return context;
+}
\ No newline at end of file
diff --git a/test/mockHelpers/fetchMockHelpers.ts b/test/testHelpers/fetchMockHelpers.ts
similarity index 100%
rename from test/mockHelpers/fetchMockHelpers.ts
rename to test/testHelpers/fetchMockHelpers.ts
diff --git a/test/generators.ts b/test/testHelpers/mockDataGenerators.ts
similarity index 98%
rename from test/generators.ts
rename to test/testHelpers/mockDataGenerators.ts
index eac524a..e284c93 100644
--- a/test/generators.ts
+++ b/test/testHelpers/mockDataGenerators.ts
@@ -1,4 +1,4 @@
-import { IEta, IOrderedStop, IRoute, IShuttle, IStop, ISystem } from "../src/entities/entities";
+import { IEta, IOrderedStop, IRoute, IShuttle, IStop, ISystem } from "../../src/entities/entities";
 
 // Use a single set of generators in case any of the
 // interfaces change in the future
diff --git a/test/testHelpers/repositorySetupHelpers.ts b/test/testHelpers/repositorySetupHelpers.ts
new file mode 100644
index 0000000..d9e48e3
--- /dev/null
+++ b/test/testHelpers/repositorySetupHelpers.ts
@@ -0,0 +1,54 @@
+import { UnoptimizedInMemoryRepository } from "../../src/repositories/UnoptimizedInMemoryRepository";
+import {
+  generateMockEtas,
+  generateMockRoutes,
+  generateMockShuttles,
+  generateMockStops,
+  generateMockSystems
+} from "./mockDataGenerators";
+
+export async function addMockSystemToRepository(repository: UnoptimizedInMemoryRepository) {
+  const mockSystems = generateMockSystems();
+  const mockSystem = mockSystems[0];
+  mockSystem.id = "1";
+  await repository.addOrUpdateSystem(mockSystem);
+
+  return mockSystem;
+}
+
+export async function addMockRouteToRepository(repository: UnoptimizedInMemoryRepository, systemId: string) {
+  const mockRoutes = generateMockRoutes();
+  const mockRoute = mockRoutes[0];
+  mockRoute.systemId = systemId;
+  await repository.addOrUpdateRoute(mockRoute);
+
+  return mockRoute;
+}
+
+export async function addMockStopToRepository(repository: UnoptimizedInMemoryRepository, systemId: string) {
+  const mockStops = generateMockStops();
+  const mockStop = mockStops[0];
+  mockStop.systemId = systemId;
+  await repository.addOrUpdateStop(mockStop);
+
+  return mockStop;
+}
+
+export async function addMockShuttleToRepository(repository: UnoptimizedInMemoryRepository, systemId: string) {
+  const mockShuttles = generateMockShuttles();
+  const mockShuttle = mockShuttles[0];
+  mockShuttle.systemId = systemId;
+  await repository.addOrUpdateShuttle(mockShuttle);
+  return mockShuttle;
+}
+
+export async function addMockEtaToRepository(repository: UnoptimizedInMemoryRepository, stopId: string, shuttleId: string) {
+  const etas = generateMockEtas();
+  const expectedEta = etas[0];
+  expectedEta.stopId = stopId;
+  expectedEta.shuttleId = shuttleId;
+  await repository.addOrUpdateEta(expectedEta);
+
+  return expectedEta;
+}
+