diff --git a/packages/app/src/Components/IrisAccount/IrisAccount.tsx b/packages/app/src/Components/IrisAccount/IrisAccount.tsx
index 20183bda..2aebb307 100644
--- a/packages/app/src/Components/IrisAccount/IrisAccount.tsx
+++ b/packages/app/src/Components/IrisAccount/IrisAccount.tsx
@@ -4,7 +4,7 @@ import { FormattedMessage } from "react-intl";
 import { injectIntl } from "react-intl";
 
 import messages from "@/Components/messages";
-import { ProfileLoader } from "@/system";
+import { System } from "@/system";
 import { LoginStore } from "@/Utils/Login";
 
 import AccountName from "./AccountName";
@@ -285,8 +285,8 @@ class IrisAccount extends Component<Props> {
   componentDidMount() {
     const session = LoginStore.snapshot();
     const myPub = session.publicKey;
-    ProfileLoader.Cache.hook(() => {
-      const profile = ProfileLoader.Cache.getFromCache(myPub);
+    System.ProfileLoader.Cache.hook(() => {
+      const profile = System.ProfileLoader.Cache.getFromCache(myPub);
       const irisToActive = profile && profile.nip05 && profile.nip05.endsWith("@iris.to");
       this.setState({ profile, irisToActive });
       if (profile && !irisToActive) {
diff --git a/packages/app/src/Hooks/useRefreshFeedcache.tsx b/packages/app/src/Hooks/useRefreshFeedcache.tsx
index 85c9ad47..3f86a78c 100644
--- a/packages/app/src/Hooks/useRefreshFeedcache.tsx
+++ b/packages/app/src/Hooks/useRefreshFeedcache.tsx
@@ -28,7 +28,7 @@ export function useRefreshFeedCache<T>(c: RefreshFeedCache<T>, leaveOpen = false
       const q = system.Query(NoopStore, sub);
       let t: ReturnType<typeof setTimeout> | undefined;
       let tBuf: Array<TaggedNostrEvent> = [];
-      q.feed.on("event", evs => {
+      q.on("event", evs => {
         if (!t) {
           tBuf = [...evs];
           t = setTimeout(() => {
@@ -41,9 +41,8 @@ export function useRefreshFeedCache<T>(c: RefreshFeedCache<T>, leaveOpen = false
       });
       q.uncancel();
       return () => {
-        q.feed.off("event");
+        q.off("event");
         q.cancel();
-        q.sendClose();
       };
     }
   }, [sub]);
diff --git a/packages/app/vite.config.ts b/packages/app/vite.config.ts
index 97e3667b..7e0c1692 100644
--- a/packages/app/vite.config.ts
+++ b/packages/app/vite.config.ts
@@ -34,6 +34,7 @@ export default defineConfig({
   assetsInclude: ["**/*.md", "**/*.wasm"],
   build: {
     outDir: "build",
+    commonjsOptions: { transformMixedEsModules: true },
   },
   clearScreen: false,
   publicDir: appConfig.get("publicDir"),
@@ -51,4 +52,7 @@ export default defineConfig({
     globals: true,
     environment: "jsdom",
   },
+  worker: {
+    format: "es",
+  },
 });
diff --git a/packages/system-react/src/useRequestBuilder.tsx b/packages/system-react/src/useRequestBuilder.tsx
index 11901928..0d685708 100644
--- a/packages/system-react/src/useRequestBuilder.tsx
+++ b/packages/system-react/src/useRequestBuilder.tsx
@@ -14,10 +14,10 @@ const useRequestBuilder = <TStore extends NoteStore, TSnapshot = ReturnType<TSto
   const subscribe = (onChanged: () => void) => {
     if (rb) {
       const q = system.Query<TStore>(type, rb);
-      q.feed.on("event", onChanged);
+      q.on("event", onChanged);
       q.uncancel();
       return () => {
-        q.feed.off("event", onChanged);
+        q.off("event", onChanged);
         q.cancel();
       };
     }
@@ -28,7 +28,7 @@ const useRequestBuilder = <TStore extends NoteStore, TSnapshot = ReturnType<TSto
   const getState = (): StoreSnapshot<TSnapshot> => {
     const q = system.GetQuery(rb?.id ?? "");
     if (q) {
-      return unwrap(q).feed?.snapshot as StoreSnapshot<TSnapshot>;
+      return q.snapshot as StoreSnapshot<TSnapshot>;
     }
     return EmptySnapshot as StoreSnapshot<TSnapshot>;
   };
diff --git a/packages/system/src/index.ts b/packages/system/src/index.ts
index 8f827507..794f40d9 100644
--- a/packages/system/src/index.ts
+++ b/packages/system/src/index.ts
@@ -1,7 +1,6 @@
 import { RelaySettings, ConnectionStateSnapshot, OkResponse } from "./connection";
 import { RequestBuilder } from "./request-builder";
-import { NoteStore, NoteStoreSnapshotData } from "./note-collection";
-import { Query } from "./query";
+import { NoteStore, NoteStoreSnapshotData, StoreSnapshot } from "./note-collection";
 import { NostrEvent, ReqFilter, TaggedNostrEvent } from "./nostr";
 import { ProfileLoaderService } from "./profile-cache";
 import { RelayCache } from "./outbox-model";
@@ -43,7 +42,15 @@ export * from "./cache/user-relays";
 export * from "./cache/user-metadata";
 export * from "./cache/relay-metric";
 
-export * from "./worker";
+export * from "./worker/system-worker";
+
+export interface QueryLike {
+  on: (event: "event", fn?: (evs: Array<TaggedNostrEvent>) => void) => void;
+  off: (event: "event", fn?: (evs: Array<TaggedNostrEvent>) => void) => void;
+  cancel: () => void;
+  uncancel: () => void;
+  get snapshot(): StoreSnapshot<NoteStoreSnapshotData>;
+}
 
 export interface SystemInterface {
   /**
@@ -65,14 +72,14 @@ export interface SystemInterface {
    * Get an active query by ID
    * @param id Query ID
    */
-  GetQuery(id: string): Query | undefined;
+  GetQuery(id: string): QueryLike | undefined;
 
   /**
    * Open a new query to relays
    * @param type Store type
    * @param req Request to send to relays
    */
-  Query<T extends NoteStore>(type: { new (): T }, req: RequestBuilder): Query;
+  Query<T extends NoteStore>(type: { new (): T }, req: RequestBuilder): QueryLike;
 
   /**
    * Fetch data from nostr relays asynchronously
diff --git a/packages/system/src/nostr-system.ts b/packages/system/src/nostr-system.ts
index 7ebc1e72..9a1b6908 100644
--- a/packages/system/src/nostr-system.ts
+++ b/packages/system/src/nostr-system.ts
@@ -20,6 +20,7 @@ import {
   UsersRelays,
   SnortSystemDb,
   EventExt,
+  QueryLike,
 } from ".";
 import { EventsCache } from "./cache/events";
 import { RelayCache, RelayMetadataLoader } from "./outbox-model";
@@ -224,16 +225,16 @@ export class NostrSystem extends EventEmitter<NostrSystemEvents> implements Syst
     this.#pool.disconnect(address);
   }
 
-  GetQuery(id: string): Query | undefined {
-    return this.#queryManager.get(id);
+  GetQuery(id: string): QueryLike | undefined {
+    return this.#queryManager.get(id) as QueryLike;
   }
 
   Fetch(req: RequestBuilder, cb?: (evs: ReadonlyArray<TaggedNostrEvent>) => void) {
     return this.#queryManager.fetch(req, cb);
   }
 
-  Query<T extends NoteStore>(type: { new (): T }, req: RequestBuilder): Query {
-    return this.#queryManager.query(type, req);
+  Query<T extends NoteStore>(type: { new (): T }, req: RequestBuilder): QueryLike {
+    return this.#queryManager.query(type, req) as QueryLike;
   }
 
   async #sendQuery(q: Query, qSend: BuiltRawReqFilter) {
diff --git a/packages/system/src/query.ts b/packages/system/src/query.ts
index fee646fa..b19ac528 100644
--- a/packages/system/src/query.ts
+++ b/packages/system/src/query.ts
@@ -116,6 +116,7 @@ export interface TraceReport {
 
 interface QueryEvents {
   trace: (report: TraceReport) => void;
+  event: (evs: ReadonlyArray<TaggedNostrEvent>) => void;
 }
 
 /**
@@ -172,6 +173,8 @@ export class Query extends EventEmitter<QueryEvents> implements QueryBase {
     this.#leaveOpen = leaveOpen ?? false;
     this.#timeout = timeout ?? 5_000;
     this.#checkTraces();
+
+    this.feed.on("event", evs => this.emit("event", evs));
   }
 
   isOpen() {
@@ -193,6 +196,10 @@ export class Query extends EventEmitter<QueryEvents> implements QueryBase {
     return this.#feed;
   }
 
+  get snapshot() {
+    return this.#feed.snapshot;
+  }
+
   handleEvent(sub: string, e: TaggedNostrEvent) {
     for (const t of this.#tracing) {
       if (t.id === sub || sub === "*") {
diff --git a/packages/system/src/worker/index.ts b/packages/system/src/worker/index.ts
index a73ee825..075aecb9 100644
--- a/packages/system/src/worker/index.ts
+++ b/packages/system/src/worker/index.ts
@@ -4,6 +4,8 @@ export const enum WorkerCommand {
   Init,
   ConnectRelay,
   DisconnectRelay,
+  Query,
+  QueryResult,
 }
 
 export interface WorkerMessage<T> {
diff --git a/packages/system/src/worker/system-worker-script.ts b/packages/system/src/worker/system-worker-script.ts
index 94786e94..6ed6ce87 100644
--- a/packages/system/src/worker/system-worker-script.ts
+++ b/packages/system/src/worker/system-worker-script.ts
@@ -1,9 +1,11 @@
 /// <reference lib="webworker" />
 
-import { NostrSystem, NostrsystemProps } from "../nostr-system";
+import { NostrSystem } from "../nostr-system";
 import { WorkerMessage, WorkerCommand } from ".";
 
-let system: NostrSystem | undefined;
+const system = new NostrSystem({
+  checkSigs: true,
+});
 
 function reply<T>(id: string, type: WorkerCommand, data: T) {
   globalThis.postMessage({
@@ -18,31 +20,19 @@ function okReply(id: string, message?: string) {
 function errorReply(id: string, message: string) {
   reply<string>(id, WorkerCommand.ErrorResponse, message);
 }
-function checkInitialized() {
-  if (system === undefined) {
-    throw new Error("System not initialized");
-  }
-}
-
 globalThis.onmessage = async ev => {
+  console.debug(ev);
   const data = ev.data as { id: string; type: WorkerCommand };
   try {
     switch (data.type) {
       case WorkerCommand.Init: {
-        const cmd = ev.data as WorkerMessage<NostrsystemProps>;
-        if (system === undefined) {
-          system = new NostrSystem(cmd.data);
-          await system.Init();
-          okReply(data.id);
-        } else {
-          errorReply(data.id, "System is already initialized");
-        }
+        await system.Init();
+        okReply(data.id);
         break;
       }
       case WorkerCommand.ConnectRelay: {
-        checkInitialized();
         const cmd = ev.data as WorkerMessage<[string, { read: boolean; write: boolean }]>;
-        await system?.ConnectToRelay(cmd.data[0], cmd.data[1]);
+        await system.ConnectToRelay(cmd.data[0], cmd.data[1]);
         okReply(data.id, "Connected");
         break;
       }
diff --git a/packages/system/src/worker/system-worker.ts b/packages/system/src/worker/system-worker.ts
index 0e57cb28..8ffaed2d 100644
--- a/packages/system/src/worker/system-worker.ts
+++ b/packages/system/src/worker/system-worker.ts
@@ -12,51 +12,110 @@ import {
   RequestBuilder,
   SystemInterface,
   TaggedNostrEvent,
+  CachedMetadata,
+  DefaultOptimizer,
+  RelayMetadataLoader,
+  RelayMetricCache,
+  RelayMetrics,
+  UserProfileCache,
+  UserRelaysCache,
+  UsersRelays,
+  QueryLike,
 } from "..";
 import { NostrSystemEvents, NostrsystemProps } from "../nostr-system";
-import { Query } from "../query";
 import { WorkerCommand, WorkerMessage } from ".";
+import { FeedCache } from "@snort/shared";
+import { EventsCache } from "../cache/events";
+import { RelayMetricHandler } from "../relay-metric-handler";
+import debug from "debug";
 
 export class SystemWorker extends EventEmitter<NostrSystemEvents> implements SystemInterface {
+  #log = debug("SystemWorker");
   #worker: Worker;
   #commandQueue: Map<string, (v: unknown) => void> = new Map();
-  checkSigs: boolean;
+  #relayCache: FeedCache<UsersRelays>;
+  #profileCache: FeedCache<CachedMetadata>;
+  #relayMetricsCache: FeedCache<RelayMetrics>;
+  #profileLoader: ProfileLoaderService;
+  #relayMetrics: RelayMetricHandler;
+  #eventsCache: FeedCache<NostrEvent>;
+  #relayLoader: RelayMetadataLoader;
+
+  get checkSigs() {
+    return true;
+  }
+
+  set checkSigs(v: boolean) {
+    // not used
+  }
 
   constructor(scriptPath: string, props: NostrsystemProps) {
     super();
-    this.checkSigs = props.checkSigs ?? false;
 
+    this.#relayCache = props.relayCache ?? new UserRelaysCache(props.db?.userRelays);
+    this.#profileCache = props.profileCache ?? new UserProfileCache(props.db?.users);
+    this.#relayMetricsCache = props.relayMetrics ?? new RelayMetricCache(props.db?.relayMetrics);
+    this.#eventsCache = props.eventsCache ?? new EventsCache(props.db?.events);
+
+    this.#profileLoader = new ProfileLoaderService(this, this.#profileCache);
+    this.#relayMetrics = new RelayMetricHandler(this.#relayMetricsCache);
+    this.#relayLoader = new RelayMetadataLoader(this, this.#relayCache);
     this.#worker = new Worker(scriptPath, {
       name: "SystemWorker",
+      type: "module",
     });
+    this.#worker.onmessage = async e => {
+      const cmd = e.data as { id: string; type: WorkerCommand; data?: unknown };
+      if (cmd.type === WorkerCommand.OkResponse) {
+        const q = this.#commandQueue.get(cmd.id);
+        q?.(cmd.data);
+        this.#commandQueue.delete(cmd.id);
+      }
+    };
   }
 
   get Sockets(): ConnectionStateSnapshot[] {
-    throw new Error("Method not implemented.");
+    return [];
   }
 
   async Init() {
-    await this.#workerRpc<void, string>(WorkerCommand.Init, undefined);
+    await this.#workerRpc(WorkerCommand.Init);
   }
 
-  GetQuery(id: string): Query | undefined {
+  GetQuery(id: string): QueryLike | undefined {
     return undefined;
   }
 
-  Query<T extends NoteStore>(type: new () => T, req: RequestBuilder): Query {
-    throw new Error("Method not implemented.");
+  Query<T extends NoteStore>(type: new () => T, req: RequestBuilder): QueryLike {
+    const chan = this.#workerRpc<[RequestBuilder], { id: string; port: MessagePort }>(WorkerCommand.Query, [req]);
+    return {
+      on: (_: "event", cb) => {
+        chan.then(c => {
+          c.port.onmessage = e => {
+            cb?.(e.data as Array<TaggedNostrEvent>);
+          };
+        });
+      },
+      off: (_: "event", cb) => {
+        chan.then(c => {
+          c.port.close();
+        });
+      },
+      cancel: () => {},
+      uncancel: () => {},
+    } as QueryLike;
   }
 
   Fetch(req: RequestBuilder, cb?: ((evs: TaggedNostrEvent[]) => void) | undefined): Promise<TaggedNostrEvent[]> {
     throw new Error("Method not implemented.");
   }
 
-  ConnectToRelay(address: string, options: RelaySettings): Promise<void> {
-    throw new Error("Method not implemented.");
+  async ConnectToRelay(address: string, options: RelaySettings) {
+    await this.#workerRpc(WorkerCommand.ConnectRelay, [address, options, false]);
   }
 
   DisconnectRelay(address: string): void {
-    throw new Error("Method not implemented.");
+    this.#workerRpc(WorkerCommand.DisconnectRelay, address);
   }
 
   HandleEvent(ev: TaggedNostrEvent): void {
@@ -72,24 +131,26 @@ export class SystemWorker extends EventEmitter<NostrSystemEvents> implements Sys
   }
 
   get ProfileLoader(): ProfileLoaderService {
-    throw new Error("Method not implemented.");
+    return this.#profileLoader;
   }
 
   get RelayCache(): RelayCache {
-    throw new Error("Method not implemented.");
+    return this.#relayCache;
   }
 
   get Optimizer(): Optimizer {
-    throw new Error("Method not implemented.");
+    return DefaultOptimizer;
   }
 
-  #workerRpc<T, R>(type: WorkerCommand, data: T, timeout = 5_000) {
+  #workerRpc<T, R>(type: WorkerCommand, data?: T, timeout = 5_000) {
     const id = uuid();
-    this.#worker.postMessage({
+    const msg = {
       id,
       type,
       data,
-    } as WorkerMessage<T>);
+    } as WorkerMessage<T>;
+    this.#log(msg);
+    this.#worker.postMessage(msg);
     return new Promise<R>((resolve, reject) => {
       let t: ReturnType<typeof setTimeout>;
       this.#commandQueue.set(id, v => {