instrumentation.ts

/**
 * Next.js runs `register()` once when a server instance starts. We use it to
 * apply DB migrations automatically (dev and in the Docker image), so the SQLite
 * file is always schema-current without a manual step. Node runtime only —
 * guarded so it never runs in the Edge runtime or during static prerender.
 */
export async function register() {
  if (process.env.NEXT_RUNTIME !== "nodejs") return;
  // On Cloudflare Workers the database is D1, migrated out-of-band via
  // `wrangler d1 migrations apply`. Skip the local libSQL migrator there — it
  // would try to touch the filesystem, which Workers don't have.
  if (
    typeof navigator !== "undefined" &&
    navigator.userAgent === "Cloudflare-Workers"
  ) {
    return;
  }
  const { runMigrations } = await import("./server/db/migrate");
  await runMigrations();
}