jarv.is/lib/helpers/prisma.ts

import { PrismaClient } from "@prisma/client";

// creating PrismaClient here prevents next.js from starting too many concurrent prisma instances and exhausting the
// number of connection pools available (especially when hot reloading from `next dev`).
// https://www.prisma.io/docs/guides/other/troubleshooting-orm/help-articles/nextjs-prisma-client-dev-practices

const prismaClientSingleton = () => {
  return new PrismaClient();
};

declare const globalThis: {
  prismaGlobal: ReturnType<typeof prismaClientSingleton>;
} & typeof global;

export const prisma = globalThis.prismaGlobal ?? prismaClientSingleton();

if (process.env.NODE_ENV !== "production") globalThis.prismaGlobal = prisma;