Rewrote turborepo. Hopefully this is a bit more clean & easy to understand for me.

apps/expo/src/utils/api.tsx

@@ -0,0 +1,50 @@
+import { QueryClient } from "@tanstack/react-query";
+import { createTRPCClient, httpBatchLink, loggerLink } from "@trpc/client";
+import { createTRPCOptionsProxy } from "@trpc/tanstack-react-query";
+import superjson from "superjson";
+
+import type { AppRouter } from "@acme/api";
+
+import { authClient } from "./auth";
+import { getBaseUrl } from "./base-url";
+
+export const queryClient = new QueryClient({
+  defaultOptions: {
+    queries: {
+      // ...
+    },
+  },
+});
+
+/**
+ * A set of typesafe hooks for consuming your API.
+ */
+export const trpc = createTRPCOptionsProxy<AppRouter>({
+  client: createTRPCClient({
+    links: [
+      loggerLink({
+        enabled: (opts) =>
+          process.env.NODE_ENV === "development" ||
+          (opts.direction === "down" && opts.result instanceof Error),
+        colorMode: "ansi",
+      }),
+      httpBatchLink({
+        transformer: superjson,
+        url: `${getBaseUrl()}/api/trpc`,
+        headers() {
+          const headers = new Map<string, string>();
+          headers.set("x-trpc-source", "expo-react");
+
+          const cookies = authClient.getCookie();
+          if (cookies) {
+            headers.set("Cookie", cookies);
+          }
+          return headers;
+        },
+      }),
+    ],
+  }),
+  queryClient,
+});
+
+export type { RouterInputs, RouterOutputs } from "@acme/api";