Hi, it’s Greg. Let’s explore this week’s changes in the Rails codebase.

Rails World 2025 - Save the date
Rails World 2025 will take place September 4 and 5, 2025, again in Amsterdam. The same venue, the same city, and good news - more tickets. The CFP is expected to open in early spring 2025, and tickets to be released shortly thereafter. Sponsorship sales opening soon (email: sponsors@rubyonrails.org).

Raise a more specific error when the job class can’t be instantiated
With this change, Rails will raise a more specific error during deserialization when a previously serialized job class is now unknown. ActiveJob::UnknownJobClassError will be raised instead of a more generic NameError to make it easily possible for adapters to tell if the NameError was raised during job execution or deserialization.

Improve error highlighting of multi-line methods in ERB templates
This pull request improves the error highlighting of multi-line methods in ERB templates.

Don’t enable YJIT in development and test environments
The development and test environment tend to reload code and redefine methods (e.g. mocking), hence YJIT isn’t generally faster in these environments. For this reason, YJIT will be disabled by default from Rails 8.1 in these environments.

Change the WEB_CONCURRENCY deploy comment default to auto
Puma introduced a new WEB_CONCURRENCY=auto setting. The config sets puma’s worker count to the count of available cpus. This pull request adds the new option to the explaining comments of a new project’s default puma.rb config file.

Don’t ask for database password when running kamal dbc
This pull request changes the kamal dbc to pass the --include-password flag to reuse the database password from database.yml.

You can view the whole list of changes here. We had 25 contributors to the Rails codebase this past week!

Until next time!