Rails 7 replaces Webpacker with importmapped Hotwire as default JavaScript setup

A new Rails skeleton will not have to require the full JavaScript toolchain with Webpack by default as Rails 7 embraces the future of Javascript.

Rails 7 adds the possibility to check on :priority for ActiveJob tests

Rails 7 gives us option to set `:priority` in test helper methods `assert_enqueued_with` and `assert_performed_with`.

Rails 7 adds choices to Javascript generator option

Rails 7 introduces built-in support for webpacker and esbuild.

Rails 7: Instrument ActiveStorage analyzers

Rails 7 adds instrumentation for ActiveStorage analyzers so that the time of analysis can be tracked.

Rails 7 adds database-specific setup and reset tasks for multi DB configurations

For multi DB Rails applications starting with Rails 7, we can now setup and reset a particular database.

Rails 7: Add from: option to ActiveSupport::TestCase#assert_no_changes

ActiveSupport::TestCase#assert_no_changes adds additional options.

Essential Skills For A Senior Rails Developer

Programming is a skill and, just like any skill, to get better at it one needs to practice, practice and practice!

Rails Arel Primer

The first look into Arel, its advantages, and examples.

Rails 7 introduces ActiveModel::API

ActiveModel::API allows adding more functionality to ActiveModel::Model and makes itself a minimum API to interact with Action Pack and Action View.

Rails 7 supports NullsFirst for all databases

Developers can now access Arel methods for null column ordering.