diff --git a/packages/effect-fc/src/QueryClient.ts b/packages/effect-fc/src/QueryClient.ts
index 3191348..6e92e52 100644
--- a/packages/effect-fc/src/QueryClient.ts
+++ b/packages/effect-fc/src/QueryClient.ts
@@ -1,4 +1,4 @@
-import { type HashMap, Pipeable, Predicate, type Subscribable, type SubscriptionRef } from "effect"
+import { Equal, Equivalence, Hash, type HashMap, Pipeable, Predicate, type Ref } from "effect"
 import type * as Query from "./Query.js"
 import type * as Result from "./Result.js"
 
@@ -9,17 +9,35 @@ export type QueryClientTypeId = typeof QueryClientTypeId
 export interface QueryClient extends Pipeable.Pipeable {
     readonly [QueryClientTypeId]: QueryClientTypeId
 
-    readonly cache: Subscribable.Subscribable<HashMap.HashMap<Query.Query.AnyKey, Result.Final<unknown, unknown, unknown>>>
+    readonly cache: Ref.Ref<HashMap.HashMap<Query.Query.AnyKey, Result.Final<unknown, unknown, unknown>>>
 }
 
 export class QueryClientImpl extends Pipeable.Class() implements QueryClient {
     readonly [QueryClientTypeId]: QueryClientTypeId = QueryClientTypeId
 
     constructor(
-        readonly cache: SubscriptionRef.SubscriptionRef<HashMap.HashMap<Query.Query.AnyKey, Result.Final<unknown, unknown, unknown>>>
+        readonly cache: Ref.Ref<HashMap.HashMap<Query.Query.AnyKey, Result.Final<unknown, unknown, unknown>>>
     ) {
         super()
     }
 }
 
 export const isQueryClient = (u: unknown): u is QueryClient => Predicate.hasProperty(u, QueryClientTypeId)
+
+
+const QueryClientCacheKeyTypeId: unique symbol = Symbol.for("@effect-fc/QueryClient/QueryClientCacheKey")
+type QueryClientCacheKeyTypeId = typeof QueryClientCacheKeyTypeId
+
+class QueryClientCacheKey implements Equal.Equal {
+    readonly [QueryClientCacheKeyTypeId]: QueryClientCacheKeyTypeId = QueryClientCacheKeyTypeId
+    constructor(readonly key: Query.Query.AnyKey) {}
+
+    [Equal.symbol](that: Equal.Equal) {
+        return isQueryClientKey(that) && Equivalence.array(Equal.equivalence())(this.key, that.key)
+    }
+    [Hash.symbol]() {
+        return 0
+    }
+}
+
+const isQueryClientKey = (u: unknown): u is QueryClientCacheKey => Predicate.hasProperty(u, QueryClientCacheKeyTypeId)