diff --git a/src/resolvers.ts b/src/resolvers.ts
index 4bc9695..8789f36 100644
--- a/src/resolvers.ts
+++ b/src/resolvers.ts
@@ -1,54 +1,95 @@
-import { Eta, OrderedStop, Resolvers, Route, Shuttle, Stop, System } from "./generated/graphql";
+import { Coordinates, Eta, OrderedStop, Resolvers, Route, Shuttle, Stop, System } from "./generated/graphql";
 import { ServerContext } from "./serverContext";
 
 export const resolvers: Resolvers<ServerContext> = {
   Query: {
-    systems: (parent, args, contextValue, info) => {
-      return contextValue.sharedMemory.systems;
+    systems: async (parent, args, contextValue, info) => {
+      const systems = await contextValue.repository.getSystems();
+      return systems.map(({
+        name,
+        id
+      }) => ({
+        name,
+        id
+      }));
     },
-    system: (parent, args, contextValue, info) => {
-      const systems = contextValue.sharedMemory.systems;
-      const system = systems.find((system) => system.id === args.id);
-      if (!system) {
-        return null;
-      }
+    system: async (parent, args, contextValue, info) => {
+      if (!args.id) return null;
+      const system = await contextValue.repository.getSystemById(args.id);
+      if (system === null) return null;
 
-      return system;
+      return {
+        name: system.name,
+        id: system.id,
+      };
     }
   },
   System: {
-    stop: (parent, args, contextValue, info) => {
-      // TODO implement interface with ID and one function to perform search
-      const stops = parent.stops;
-      const stop = stops.find((stop) => stop.id === args.id);
-      if (!stop) {
-        return null;
-      }
-
-      return stop;
+    routes: async (parent, args, contextValue, info) => {
+      const routes = await contextValue.repository.getRoutesBySystemId(parent.id);
+      return routes.map(({
+        color,
+        id,
+        name,
+        polylineCoordinates,
+      }) => ({
+        color,
+        id,
+        name,
+        polylineCoordinates,
+      }));
     },
-    route: (parent, args, contextValue, info) => {
-      const routes = parent.routes
-      const route = routes.find((route) => route.id === args.id);
-      if (!route) {
-        return null;
-      }
-
-      return route;
+    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,
+      }));
     },
-    shuttle: (parent, args, contextValue, info) => {
-      const shuttles = parent.shuttles;
-      const shuttle = shuttles.find((shuttle) => shuttle.id === args.id);
-      if (!shuttle) {
-        return null;
-      }
+    stop: async (parent, args, contextValue, info) => {
+      if (!args.id) return null;
+      const stop = await contextValue.repository.getStopById(args.id);
+      if (stop === null) return null;
 
-      return shuttle;
+      return {
+        id: stop.id,
+        name: stop.name,
+        coordinates: stop.coordinates as Coordinates,
+      };
+    },
+    route: async (parent, args, contextValue, info) => {
+      if (!args.id) return null;
+      const route = await contextValue.repository.getRouteById(args.id);
+      if (route === null) return null;
+
+      return {
+        color: route.color,
+        id: route.id,
+        name: route.name,
+        polylineCoordinates: route.polylineCoordinates as Coordinates[],
+      };
+    },
+    shuttle: async (parent, args, contextValue, info) => {
+      if (!args.id) return null;
+      const shuttle = await contextValue.repository.getShuttleById(args.id);
+      if (shuttle === null) return null;
+
+      return {
+        coordinates: shuttle.coordinates as Coordinates,
+        id: shuttle.id,
+        name: shuttle.name,
+      };
     }
   },
   Route: {
     nextOrderedStop: (parent, args, contextValue, info) => {
-      const orderedStop = parent.orderedStops.find((orderedStop) => orderedStop.stop.id === args.forStopId);
+      const orderedStop = parent.orderedStops?.find((orderedStop) => orderedStop.stop?.id === args.forStopId);
       if (!orderedStop || !orderedStop.nextStop) {
         return null;
       }
@@ -58,7 +99,7 @@ export const resolvers: Resolvers<ServerContext> = {
   },
   Shuttle: {
     eta: (parent, args, contextValue, info) => {
-      const etaForNextStop = parent.etas.find((eta) => eta.stop.id === args.forStopId);
+      const etaForNextStop = parent.etas?.find((eta) => eta.stop.id === args.forStopId);
       if (!etaForNextStop) {
         return null;
       }
@@ -66,4 +107,59 @@ export const resolvers: Resolvers<ServerContext> = {
       return etaForNextStop;
     },
   },
+  Stop: {
+    orderedStops: async (parent, args, contextValue, info) => {
+      const orderedStops = await contextValue.repository.getOrderedStopsByStopId(parent.id);
+
+      const computedOrderedStops = await Promise.all(orderedStops.map(async ({
+        routeId,
+        stopId,
+      }): Promise<OrderedStop | null> => {
+        const stop = await contextValue.repository.getStopById(stopId);
+        const route = await contextValue.repository.getRouteById(routeId);
+        if (stop === null || route === null) return null;
+
+        return {
+          stop: {
+            coordinates: stop.coordinates,
+            id: stop.id,
+            name: stop.name,
+          },
+          route: {
+            name: route.name,
+            id: route.id,
+            polylineCoordinates: route.polylineCoordinates,
+            color: route.color,
+          },
+        };
+      }));
+
+      if (!computedOrderedStops.every((value) => value !== null)) {
+        return [];
+      }
+
+      return computedOrderedStops as OrderedStop[];
+    }
+  },
+  OrderedStop: {
+    nextStop: async (parent, args, contextValue, info): Promise<OrderedStop | null> => {
+      const routeId = parent.route.id;
+      const stopId = parent.stop.id;
+
+      const nextOrderedStop = await contextValue.repository.getOrderedStopByRouteAndStopId(routeId, stopId);
+      if (!nextOrderedStop) return null;
+
+      const nextStopObject = await contextValue.repository.getStopById(nextOrderedStop.stopId);
+      if (!nextStopObject) return null;
+
+      return {
+        route: parent.route,
+        stop: {
+          coordinates: nextStopObject.coordinates as Coordinates,
+          id: nextStopObject.id,
+          name: nextStopObject.name,
+        }
+      }
+    },
+  }
 };
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