I switched a codebase from local Postgres database to Vercel Postgres, which comes with its own optimized package.

I used this to connect Lucia Auth:

import { postgres as postgresAdapter } from '@lucia-auth/adapter-postgresql'
import postgres from 'postgres'

const POSTGRES_URL = //..lookup from env variables

const postgresDatabase = postgres(POSTGRES_URL)

const auth = lucia({
  adapter: postgresAdapter(
    postgresDatabase,
    dbConfig
  ),
	//...
})

With Vercel Postgres, I used:

import { pg } from '@lucia-auth/adapter-postgresql'
import { db } from '@vercel/postgres'

const auth = lucia({
  adapter: pg(db, dbConfig),
	//...
})

The db now already know how to look up the environment variable POSTGRES_URL

Lessons in this unit:

0:	Introduction
1:	Introduction to PostgreSQL
2:	How to install PostgreSQL on macOS
3:	How to create a PostgreSQL database
4:	Navigating Databases in PostgreSQL
5:	PostgreSQL User Permissions
6:	Tables and Data Types
7:	Where to host a PostgreSQL database
8:	PostgreSQL vs MySQL
9:	Troubleshooting PostgreSQL
10:	Vercel Postgres, no transactions?
11:	▶︎ Set up Lucia Auth for local Postgres DB vs Vercel Postgres
12:	Connect to Postgres local vs Vercel Postgres with Kysely