You need to have PostgresQL (with PostGIS extensions) installed on you environment with a database called points. After that, create .env file and fill it with the following values:
PGUSER=postgres
PGHOST=localhost
PGPASSWORD=
PGDATABASE=points
PGPORT=5432
Make sure you have the correct host, username, password and database name.
Next, run the setup file:
ts-node setup.ts
This will install some random points.
Next, run the server:
ts-node express.ts
Open mapbox.html and replace mapboxgl.accessToken with your mapbox access token. Now open this file into the browser.