NextJS 15 + AWS Amplify

good evening! I am building a NextJS 15 + AWS Amplify application! I know that AWS doesn't yet provide support for NextJS 15, but since this is a new application and AWS will soon offer support for NextJS 15, I decided to start studying it!

In this application, I am working with a business logic focused on server actions, and so far, I have completed the entire custom integration with Cognito for user creation, confirmation, password recovery, and login. However, regarding the last item, when I execute the signIn function from the aws-amplify package, I get a response indicating that the login was successful as you can see bellow.

page.tsx

'use client'

import Link from "next/link";
import Image from "next/image";
import {useActionState} from "react";
import {signInFormType} from "./schema";
import {Brand} from "@/components/ui/brand";
import {Label} from "@/components/ui/label";
import {Submit} from "@/components/ui/submit";
import {Button} from "@/components/ui/button";
import {Heading} from "@/components/ui/heading";
import {Divider} from "@/components/ui/divider";
import {signInWithRedirect} from "aws-amplify/auth";
import {Input, InputError} from "@/components/ui/input";
import {signInWithCredentialsAction} from "./controller";
import {Alert, AlertDescription} from "@/components/ui/alert";

export default function Page() {
  const [state, formAction] = useActionState(signInWithCredentialsAction, {} as signInFormType);

  return (
    <>
      <Brand className="text-5xl"/>

      <Heading title="Sign In" description="Enter your credentials in the fields below to access your dashboard."/>

      {state?.message && (<Alert variant={state?.success ? 'default' : 'destructive'}><AlertDescription>{state?.message}</AlertDescription></Alert>)}

      <form action={formAction} className="space-y-4">
        <div>
          <Label>Email Address</Label>
          <Input type="text" name="email" defaultValue={state?.data?.email || undefined} placeholder="[email protected]"/>
          <InputError message={state?.errors?.fieldErrors?.email} />
        </div>

        <div>
          <div className="flex-between">
            <Label>Password</Label>
            <Link href="/forgot-password" className="link text-sm pr-1">Forgot your password?</Link>
          </div>

          <Input type="password" name="password" placeholder="your password"/>
          <InputError message={state?.errors?.fieldErrors?.password} />
        </div>

        <div className="pt-4">
          <Submit behavior="full">Sign In</Submit>
        </div>
      </form>

      <div className="text-center text-muted-foreground text-sm">
        Don't have an account? <Link href="/register" className="link !font-bold">Sign Up</Link>
      </div>

      <Divider text="ou"/>

      <Button variant="outline" behavior="full" size="sm" onClick={async () =>  await signInWithRedirect({provider: 'Google'})}>
        <Image src="/google.svg" width={24} height={24} alt="Google" className="size-4"/>
        <span className="normal-case font-bold">sign in with Google</span>
      </Button>

      <div className="flex flex-col items-center justify-center">
        <Link href="/" className="link clicked">Home Page</Link>
      </div>
    </>
  )
}

On the server action side, I have the code below.

controller.tsx

'use server'

import {signIn, signInWithRedirect} from "aws-amplify/auth";
import {redirect} from "next/navigation";
import {signInSchema, signInSchemaErrorType, signInSchemaType} from "./schema";

export async function signInWithCredentialsAction(prevState: unknown, payload: FormData) {
  const validated = signInSchema.safeParse(Object.fromEntries(payload.entries()));

  if (!validated.success) {
    return {
      errors: validated.error.formErrors as signInSchemaErrorType,
      data: Object.fromEntries(payload.entries()) as signInSchemaType
    }
  }

  const {nextStep} = await signIn({
    username: validated.data.email,
    password: validated.data.password
  });

  if (isSignedIn) {
    return redirect(`/dashboard`);
  }

  return {
    success: false,
    message: 'Login could not be completed.',
    data: Object.fromEntries(payload.entries()) as signInSchemaType
  };
}

and this is the response that I have when I call the signIn method:

isSignedIn: true
nextStep: { signInStep: 'DONE' }

I also wrote some helper functions to assist with retrieving the authenticated user and the user's session.

/lib/amplify.ts

import {cookies} from "next/headers";
import {ResourcesConfig} from "aws-amplify";
import outputs from "@/amplify_outputs.json";
import {type Schema} from "@/amplify/data/resource";
import {createServerRunner} from "@aws-amplify/adapter-nextjs";
import {getCurrentUser, fetchAuthSession} from "aws-amplify/auth/server";
import {generateServerClientUsingCookies} from "@aws-amplify/adapter-nextjs/data";

export const {runWithAmplifyServerContext} = createServerRunner({config: outputs as ResourcesConfig});

export const cookieBasedClient = generateServerClientUsingCookies<Schema>({config: outputs as ResourcesConfig, cookies, authMode: "iam"});

export const isAuthenticated = async (): Promise<boolean> => {
  return await runWithAmplifyServerContext({
    nextServerContext: {cookies},
    async operation(contextSpec) {
      try {
        const user = await getCurrentUser(contextSpec);

        return !!user;
      } catch {
        return false;
      }
    },
  });
};

but for some reason that I don't understand, when I call the method isAuthenticated() I aways get an false as a return.

and as I'm studying NextJs and AWS Amplify for a couple of weeks I'm a little bit lost! If someone could help me on this case, just to make some workaround while AWS don't release the Next15 support I will be very thankful.