Sourced from activesupport's releases.

8.1.3

Active Support

• Fix JSONGemCoderEncoder to correctly serialize custom object hash keys.

  When hash keys are custom objects whose as_json returns a Hash, the encoder now calls to_s on the original key object instead of on the as_json result.

  Before: hash = {CustomKey.new(123) => "value"} hash.to_json # => {"{:id=>123}":"value"}

  After: hash.to_json # => {"custom_123":"value"}

  Dan Sharp

• Fix inflections to better handle overlapping acronyms.

  ActiveSupport::Inflector.inflections(:en) do |inflect|
    inflect.acronym "USD"
    inflect.acronym "USDC"
  end
  "USDC".underscore # => "usdc"

  Said Kaldybaev

• Silence Dalli 4.0+ warning when using ActiveSupport::Cache::MemCacheStore.

  zzak

Active Model

• Fix Ruby 4.0 delegator warning when calling inspect on attributes.

  Hammad Khan

• Fix NoMethodError when deserialising Type::Integer objects marshalled under Rails 8.0.

  The performance optimisation that replaced @range with @max/@min broke Marshal compatibility. Objects serialised under 8.0 (with @range) and deserialised under 8.1 (expecting @max/@min) would crash with undefined method '<=' for nil because Marshal.load restores instance variables without calling initialize.

... (truncated)

Sourced from activesupport's changelog.

Rails 8.1.3 (March 24, 2026)

• Fix JSONGemCoderEncoder to correctly serialize custom object hash keys.

  When hash keys are custom objects whose as_json returns a Hash, the encoder now calls to_s on the original key object instead of on the as_json result.

  Before: hash = {CustomKey.new(123) => "value"} hash.to_json # => {"{:id=>123}":"value"}

  After: hash.to_json # => {"custom_123":"value"}

  Dan Sharp

• Fix inflections to better handle overlapping acronyms.

  ActiveSupport::Inflector.inflections(:en) do |inflect|
    inflect.acronym "USD"
    inflect.acronym "USDC"
  end
  "USDC".underscore # => "usdc"

  Said Kaldybaev

• Silence Dalli 4.0+ warning when using ActiveSupport::Cache::MemCacheStore.

  zzak

• fa8f081 Preparing for 8.1.3 release
• 63cef3d Merge branch '8-1-sec' into 8-1-stable
• c315744 Merge pull request #56889 from alpaca-tc/support-spring-on-test-environment
• 2ac86a8 Revert benchmark.rb to a silent shim (#56832)
• 8e8c955 Merge pull request #56785 from drsharp/dan/fix-json-encoder-bug
• 38e8df6 Fix activesupport/CHANGELOG.md offense at 8-1-stable
• f5266ee Merge pull request #56679 from Saidbek/fix-overlapping-acronyms-order
• 8080d2d Fix changelog formatting
• 594357c Merge pull request #56652 from zzak/re-56588
• 055902a Handle Ruby 4.1 stabby lambda in Proc#source_location start_column
• Additional commits viewable in compare view