Handling multiple postgres user permissions for web app

Hi everyone! I’m in need of some help handling connections from my express server to my postgres db in my web app.
I’m a newbie and still trying to find out how to best handle connections to the database.

Some background info
I’m currently using .sql files to create users and roles. I have 3 different users created inside of postgres, 1) writer_user 2) reader_user 3) remover_user. Each user has specific permissions to their name (i.e., reader only has SELECT permissions to the specific schema). I’m currently creating 3 different connections to the pg database in the express server to handle the different connections.

Problem
Does it make sense to handle these 3 connections in this way? Should I even be making these different users or should it just be 1 postgres user with SELECT, INSERT, UPDATE, and DELETE permissions?