diff --git a/integration-tests/aws-sdk/setup.ts b/integration-tests/aws-sdk/setup.ts
index 9e8665a3..9b56dcd0 100644
--- a/integration-tests/aws-sdk/setup.ts
+++ b/integration-tests/aws-sdk/setup.ts
@@ -13,6 +13,7 @@ import {
   TriggersService,
 } from "../../src/services";
 import { CognitoServiceFactoryImpl } from "../../src/services/cognitoService";
+import { NoOpCache } from "../../src/services/dataStore/cache";
 import { StormDBDataStoreFactory } from "../../src/services/dataStore/stormDb";
 import { otp } from "../../src/services/otp";
 import { UserPoolServiceFactoryImpl } from "../../src/services/userPoolService";
@@ -38,7 +39,10 @@ export const withCognitoSdk =
       dataDirectory = await mkdtemp("/tmp/cognito-local:");
       const ctx = { logger };
 
-      const dataStoreFactory = new StormDBDataStoreFactory(dataDirectory);
+      const dataStoreFactory = new StormDBDataStoreFactory(
+        dataDirectory,
+        new NoOpCache()
+      );
       const cognitoServiceFactory = new CognitoServiceFactoryImpl(
         dataDirectory,
         clock,
@@ -66,7 +70,10 @@ export const withCognitoSdk =
         port: 0,
       });
 
-      const address = httpServer.address()!;
+      const address = httpServer.address();
+      if (!address) {
+        throw new Error("HttpServer has no address");
+      }
       const url =
         typeof address === "string"
           ? address
diff --git a/integration-tests/cognitoService.test.ts b/integration-tests/cognitoService.test.ts
index d00d40b2..93162704 100644
--- a/integration-tests/cognitoService.test.ts
+++ b/integration-tests/cognitoService.test.ts
@@ -7,6 +7,7 @@ import {
 } from "../src/services/cognitoService";
 import fs from "fs";
 import { promisify } from "util";
+import { NoOpCache } from "../src/services/dataStore/cache";
 import { StormDBDataStoreFactory } from "../src/services/dataStore/stormDb";
 import { UserPoolServiceFactoryImpl } from "../src/services/userPoolService";
 
@@ -21,7 +22,10 @@ describe("Cognito Service", () => {
     dataDirectory = await mkdtemp("/tmp/cognito-local:");
 
     const clock = new DateClock();
-    const dataStoreFactory = new StormDBDataStoreFactory(dataDirectory);
+    const dataStoreFactory = new StormDBDataStoreFactory(
+      dataDirectory,
+      new NoOpCache()
+    );
 
     factory = new CognitoServiceFactoryImpl(
       dataDirectory,
diff --git a/integration-tests/dataStore.test.ts b/integration-tests/dataStore.test.ts
index cff3886a..f000faa0 100644
--- a/integration-tests/dataStore.test.ts
+++ b/integration-tests/dataStore.test.ts
@@ -1,7 +1,8 @@
-import StormDB from "stormdb";
-import { TestContext } from "../src/__tests__/testContext";
 import fs from "fs";
+import StormDB from "stormdb";
 import { promisify } from "util";
+import { TestContext } from "../src/__tests__/testContext";
+import { InMemoryCache, NoOpCache } from "../src/services/dataStore/cache";
 import { DataStoreFactory } from "../src/services/dataStore/factory";
 import { StormDBDataStoreFactory } from "../src/services/dataStore/stormDb";
 
@@ -15,7 +16,7 @@ describe("Data Store", () => {
 
   beforeEach(async () => {
     path = await mkdtemp("/tmp/cognito-local:");
-    factory = new StormDBDataStoreFactory(path);
+    factory = new StormDBDataStoreFactory(path, new NoOpCache());
   });
 
   afterEach(() =>
@@ -303,5 +304,29 @@ describe("Data Store", () => {
 
       expect(result).toEqual(date);
     });
+
+    it("supports caching data stores across creates for the same id", async () => {
+      const factory = new StormDBDataStoreFactory(path, new InMemoryCache());
+
+      const dataStore1 = await factory.create(TestContext, "example", {});
+      const dataStore2 = await factory.create(TestContext, "example", {});
+      const dataStore3 = await factory.create(TestContext, "example2", {});
+
+      await dataStore1.set(TestContext, "One", 1);
+      await dataStore2.set(TestContext, "Two", 2);
+      await dataStore3.set(TestContext, "Three", 3);
+
+      expect(await dataStore1.getRoot(TestContext)).toEqual({
+        One: 1,
+        Two: 2,
+      });
+      expect(await dataStore2.getRoot(TestContext)).toEqual({
+        One: 1,
+        Two: 2,
+      });
+      expect(await dataStore3.getRoot(TestContext)).toEqual({
+        Three: 3,
+      });
+    });
   });
 });
diff --git a/integration-tests/userPoolService.test.ts b/integration-tests/userPoolService.test.ts
index 76f8d9fc..db4c8927 100644
--- a/integration-tests/userPoolService.test.ts
+++ b/integration-tests/userPoolService.test.ts
@@ -1,14 +1,9 @@
 import fs from "fs";
 import { promisify } from "util";
 import { TestContext } from "../src/__tests__/testContext";
-import {
-  CognitoService,
-  CognitoServiceImpl,
-  DateClock,
-  UserPoolService,
-  UserPoolServiceImpl,
-} from "../src/services";
+import { CognitoService, DateClock, UserPoolService } from "../src/services";
 import { CognitoServiceFactoryImpl } from "../src/services/cognitoService";
+import { NoOpCache } from "../src/services/dataStore/cache";
 import { StormDBDataStoreFactory } from "../src/services/dataStore/stormDb";
 import { UserPoolServiceFactoryImpl } from "../src/services/userPoolService";
 
@@ -25,7 +20,10 @@ describe("User Pool Service", () => {
   beforeEach(async () => {
     dataDirectory = await mkdtemp("/tmp/cognito-local:");
     const clock = new DateClock();
-    const dataStoreFactory = new StormDBDataStoreFactory(dataDirectory);
+    const dataStoreFactory = new StormDBDataStoreFactory(
+      dataDirectory,
+      new NoOpCache()
+    );
 
     cognitoClient = await new CognitoServiceFactoryImpl(
       dataDirectory,
diff --git a/src/server/defaults.ts b/src/server/defaults.ts
index ade75422..8922cd51 100644
--- a/src/server/defaults.ts
+++ b/src/server/defaults.ts
@@ -7,6 +7,7 @@ import {
   TriggersService,
 } from "../services";
 import { CognitoServiceFactoryImpl } from "../services/cognitoService";
+import { InMemoryCache } from "../services/dataStore/cache";
 import { StormDBDataStoreFactory } from "../services/dataStore/stormDb";
 import { ConsoleMessageSender } from "../services/messageDelivery/consoleMessageSender";
 import { MessageDeliveryService } from "../services/messageDelivery/messageDelivery";
@@ -28,14 +29,17 @@ export const createDefaultServer = async (
   const config = await loadConfig(
     ctx,
     // the config gets a separate factory because it's stored in a different directory
-    new StormDBDataStoreFactory(configDirectory)
+    new StormDBDataStoreFactory(configDirectory, new InMemoryCache())
   );
 
   logger.debug({ config }, "Loaded config");
 
   const clock = new DateClock();
 
-  const dataStoreFactory = new StormDBDataStoreFactory(dataDirectory);
+  const dataStoreFactory = new StormDBDataStoreFactory(
+    dataDirectory,
+    new InMemoryCache()
+  );
 
   const cognitoServiceFactory = new CognitoServiceFactoryImpl(
     dataDirectory,
diff --git a/src/services/dataStore/cache.ts b/src/services/dataStore/cache.ts
new file mode 100644
index 00000000..0df40704
--- /dev/null
+++ b/src/services/dataStore/cache.ts
@@ -0,0 +1,27 @@
+import { DataStore } from "./dataStore";
+
+export type DataStoreCache = {
+  get(key: string): DataStore | null;
+  set(key: string, value: DataStore): void;
+};
+
+export class InMemoryCache implements DataStoreCache {
+  private readonly cache: Record<string, DataStore> = {};
+
+  get(key: string): DataStore | null {
+    return this.cache[key];
+  }
+
+  set(key: string, value: DataStore): void {
+    this.cache[key] = value;
+  }
+}
+
+export class NoOpCache implements DataStoreCache {
+  get(): DataStore | null {
+    return null;
+  }
+
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  set(): void {}
+}
diff --git a/src/services/dataStore/stormDb.ts b/src/services/dataStore/stormDb.ts
index ff642b7c..ad65bbf9 100644
--- a/src/services/dataStore/stormDb.ts
+++ b/src/services/dataStore/stormDb.ts
@@ -2,6 +2,7 @@ import fs from "fs";
 import StormDB from "stormdb";
 import { promisify } from "util";
 import { Context } from "../context";
+import { DataStoreCache } from "./cache";
 import { DataStore } from "./dataStore";
 import { DataStoreFactory } from "./factory";
 
@@ -98,9 +99,11 @@ const createStormDBInstance = (directory: string, id: string): StormDB => {
 
 export class StormDBDataStoreFactory implements DataStoreFactory {
   private readonly directory: string;
+  private readonly cache: DataStoreCache;
 
-  public constructor(directory: string) {
+  public constructor(directory: string, dataStoreCache: DataStoreCache) {
     this.directory = directory;
+    this.cache = dataStoreCache;
   }
 
   public async create(
@@ -111,6 +114,12 @@ export class StormDBDataStoreFactory implements DataStoreFactory {
     ctx.logger.debug({ id }, "createDataStore");
     await mkdir(this.directory, { recursive: true });
 
+    const cachedDb = this.cache.get(id);
+    if (cachedDb) {
+      ctx.logger.debug({ id }, "Using cached data store");
+      return cachedDb;
+    }
+
     ctx.logger.debug({ id }, "Creating new data store");
     const db = createStormDBInstance(this.directory, id);
 
@@ -119,6 +128,10 @@ export class StormDBDataStoreFactory implements DataStoreFactory {
     ctx.logger.debug({ store: db.value() }, "DataStore.save");
     await db.save();
 
-    return new StormDBDataStore(db);
+    const dataStore = new StormDBDataStore(db);
+
+    this.cache.set(id, dataStore);
+
+    return dataStore;
   }
 }