Next.js integration

The Fidemark SDK runs in Node.js: use it from a Next.js Route Handler or Server Action, never from a "use client" component (the EAS contract calls require server-side RPC access for the read-only path, and you don’t want signing keys in browser bundles).

App Router pattern

app/api/attest-ai/route.ts:

import { NextRequest, NextResponse } from "next/server";
import { Fidemark } from "@fidemark/sdk";

const fidemark = new Fidemark({
  network: "base-sepolia",
  privateKey: process.env.FIDEMARK_PRIVATE_KEY!,
});

export async function POST(req: NextRequest) {
  const { content, modelId, prompt, parameters } = await req.json();

  const result = await fidemark.attestAI({
    content,
    modelId,
    provider: "anthropic",
    prompt,
    parameters,
  });

  return NextResponse.json(result);
}

Verification page (server component)

app/[uid]/page.tsx:

import { Fidemark } from "@fidemark/sdk";
import { JsonRpcProvider } from "ethers";

const fidemark = new Fidemark({
  network: "base-sepolia",
  provider: new JsonRpcProvider("https://sepolia.base.org"),
});

export default async function Verify({ params }: { params: Promise<{ uid: string }> }) {
  const { uid } = await params;
  const att = await fidemark.verify(uid);
  return <pre>{JSON.stringify(att, null, 2)}</pre>;
}

This is the same pattern verify.fidemark.dev uses: a server component renders the attestation as static-feeling HTML; the verifier doesn’t need a wallet or any JavaScript.

Caveats

• Add transpilePackages: ["@fidemark/sdk"] to next.config.ts.
• Don’t import the SDK into client components: keep RPC and key handling server-side.
• For high-traffic verify pages, cache verify() results: an attestation is immutable except for revocation, so a short cache (~30 seconds) is safe.