Use Kysely with Astro and Postgres

Create the database

npx ezhst db create main
npx ezhst db info --json
npx ezhst env set DATABASE_URL="postgresql://..."

The connection string uses a public host with TLS, so it works from your laptop too. Put it in your local .env for development.

Install Kysely

npm i kysely pg
npm i -D @types/pg

Create the client

import { Kysely, PostgresDialect } from "kysely";
import { Pool } from "pg";

export const db = new Kysely<Database>({
  dialect: new PostgresDialect({
    pool: new Pool({ connectionString: process.env.DATABASE_URL, max: 5 }),
  }),
});

Define the Database interface yourself or generate it with kysely-codegen. A pool of 5 leaves room within the limit of 20 connections per database.

Add export const prerender = false to endpoints when your output is static, so they run per request.

Query it from a route

import { db } from "../../lib/db";
export const GET = async ({ request }: { request: Request }) => {
  const rows = await db.selectFrom("users").selectAll().limit(20).execute();
  return Response.json(rows);
};

Run migrations

Run migrations from your machine, with DATABASE_URL set to the EasyHost connection string.

npx kysely migrate:latest

Commit the migration files so every environment applies the same changes.

Deploy

npx ezhst deploy

Each database allows 20 concurrent connections, and Astro shares them across requests. See the Astro hub for every Astro guide, or free Astro hosting for what is included. See also the Postgres product page.

Frequently asked questions

Is Postgres free for my Astro app?

Yes. Each EasyHost project can have one Postgres 16 database with no expiry date.

Can I use Kysely locally against the same database?

Yes. The connection string works from outside EasyHost. A separate development database is safer once you have real data.

Start for free

Install the skill, choose Global or Local, then tell your agent to deploy. No credit card, no config files.

npx ezhst skill install