heroku db-spec -- the :sslmode/:ssl/:sslfactory trifecta were necessary for me to let my laptop connect to my remote heroku postgres db.

0-reset-and-init-db.sql

DROP TABLE IF EXISTS users CASCADE;

CREATE TABLE users (
  id            serial       PRIMARY KEY,
  uname         text         NOT NULL  UNIQUE,
  digest        text         NOT NULL,
  created_at    timestamp    NOT NULL  DEFAULT CURRENT_TIMESTAMP
);

db.clj

(ns xxx.db
  (:require
   [clojure.java.jdbc :as j]
   [clojure.java.io :as io]
   [clojure.string :as str]
   [environ.core :as environ]))

(def db-spec {:classname "org.postgresql.Driver"
              :subprotocol "postgresql"
              :subname "//ec2-XX-XXX-XXX-XX.compute-1.amazonaws.com:5432/dbname"
              :user "xxxxx"
              :password "xxxxxxxxxxxx"
              :sslmode "require"
              :ssl true
              :sslfactory (when-not (:production environ/env)
                            "org.postgresql.ssl.NonValidatingFactory")})

(defn reset-db! []
  (j/execute! db-spec [(slurp (io/resource "sql/migrations/0-reset-and-init-db.sql"))]))

(reset-db!)  ;=> [0]