Rails 6.1 revamps ActiveModel Errors with a new API
Rails 6.1 refactors `ActiveModel::Errors` to behave more like a rich object, improving its integration with validations and serialization.
GAURAV VARMA
Rails 6.1 adds ActiveRecord delegated types for polymorphism
Rails 6.1 introduces delegated_type, a more elegant and flexible alternative to classic polymorphic associations with helpful query and helper methods out of the box.
Rails 6.1 allows destroying associations asynchronously
Rails 6.1 introduces `:destroy_async`, allowing associated records to be deleted via background jobs—improving performance and preventing long request times.
Rails 6.1 introduces Strict Loading to catch N+1 queries
Rails 6.1 adds strict loading mode, which raises errors when accessing associations that weren’t eager-loaded.
Rails 6.1 enables per-database connection switching & sharding
Rails 6.1 enhances multi-database support with fine-grained connection switching and horizontal sharding, giving developers more control over read/write routing across databases.