Create a Rails App with PostgreSQL and GitHub

Use this when starting a new Rails project that should use PostgreSQL and live on GitHub.

Verify Ruby and Rails

Check the active Ruby and Rails versions before creating the app. These should come from the Ruby version managed by mise.

ruby -v
rails -v

Install Ruby with mise

Install and activate Ruby with mise if the project needs a newer Ruby version. This is usually a one-time setup step for each Ruby version.

mise use ruby@latest
ruby -v

Install or update Rails

If rails -v shows an older version than expected, install the latest Rails gem for the active Ruby version.

gem install rails
mise reshim
rails -v

mise reshim refreshes command shims so the rails command points at the newly installed gem executable.

Create the Rails app

Create the app with PostgreSQL as the database.

rails new APP_NAME -d postgresql
cd APP_NAME

Optional rails new flags

Add these flags when creating the app if the project needs a specific frontend, database, or setup style.

rails new APP_NAME -d postgresql -j esbuild -c tailwind

Options marked (default) do not need to be specified when using the standard Rails defaults.

Database

Flag	Use
-d postgresql	Use PostgreSQL as the database.
-d mysql	Use MySQL as the database.
-d sqlite3	(default) Use SQLite as the database.

JavaScript

Flag	Use
-j importmap	(default) Use import maps for JavaScript.
-j esbuild	Use esbuild for JavaScript bundling.
-j rollup	Use Rollup for JavaScript bundling.
-j webpack	Use webpack for JavaScript bundling.

Stylesheets

Flag	Use
-c tailwind	Use Tailwind CSS.
-c bootstrap	Use Bootstrap.
-c bulma	Use Bulma.
-c sass	Use Sass.

Other Utilities

Flag	Use
--api	Create an API-only Rails app.
--skip-test	Skip Rails test files.
--skip-system-test	Skip system test files.
--skip-action-mailer	Skip Action Mailer.
--skip-action-mailbox	Skip Action Mailbox.
--skip-action-text	Skip Action Text.
--skip-active-storage	Skip Active Storage.
--skip-hotwire	Skip Hotwire.
--skip-jbuilder	Skip Jbuilder.
--skip-bundle	Create the app without running bundle install.

Create the databases

Create the local development and test databases.

bin/rails db:create

Check the app locally

Start the Rails server and open the local app in the browser.

bin/rails server

Make the first commit

Rails initializes Git by default. Add the generated files and commit the app baseline.

git status
git add .
git commit -m "Initial Rails app"

Push main to GitHub

Create an empty GitHub repo first, then add the SSH remote and push main.

git branch -M main
git remote add origin git@github.com:USERNAME/REPO.git
git push -u origin main

Create and push dev

After main is pushed, create dev for regular development work.

git checkout -b dev
git push -u origin dev

Sources

• The Rails Command Line