Start a shell for the postgres user:
```
~$ sudo -u postgres bash
```
Generate a new database password:
```
$ ruby -e 'puts rand(2**128).to_s(36)'
yourgeneratedpassword
```
Record this. You'll need it when you set up the Rails server later.

Create a database user with the password you generated:

$ createuser --encrypted -R -S --pwprompt {{service_role}}
  Enter password for new role: yourgeneratedpassword
  Enter it again: yourgeneratedpassword

Create a database owned by the new user:

$ createdb {{service_database}} -T template0 -E UTF8 -O {{service_role}}

Enable the pg_trgm extension

$ psql {{service_database}} -c "CREATE EXTENSION IF NOT EXISTS pg_trgm"

Exit the postgres user shell:
```
$ exit
```