lithic-com · stainless-app · Apr 21, 2026 · Apr 21, 2026 · Apr 22, 2026 · Apr 24, 2026
diff --git a/.release-please-manifest.json b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.12.0"
+  ".": "0.13.0"
 }
diff --git a/.stats.yml b/.stats.yml
@@ -1,4 +1,4 @@
 configured_endpoints: 191
-openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/lithic%2Flithic-d29b68bb85936070878d8badaa8a7c5991313285e70a990bc812c838eba85373.yml
-openapi_spec_hash: 54b44da68df22eb0ea99f2bc564667a2
-config_hash: ac8326134e692f3f3bdec82396bbec80
+openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/lithic/lithic-0f374e78a0212145a2f55a55dfc39a612de19094d5152ae26b1bc74b01b9e343.yml
+openapi_spec_hash: ec888cdaebea979a2cd6231ca04c346c
+config_hash: 01dfc901bb6d54b0f582155d779bcbe0
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,5 +1,33 @@
 # Changelog
 
+## 0.13.0 (2026-05-06)
+
+Full Changelog: [v0.12.0...v0.13.0](https://github.com/lithic-com/lithic-ruby/compare/v0.12.0...v0.13.0)
+
+### Features
+
+* **api:** add AMEX network value to settlement models ([a209f16](https://github.com/lithic-com/lithic-ruby/commit/a209f16480d3a19ba50c00ea1c5b8c6b3950129e))
+* **api:** add CARD_TRANSACTION_UPDATE event stream to auth_rules ([7f395eb](https://github.com/lithic-com/lithic-ruby/commit/7f395eb5b666d1d5563705da6ebe8dd7d8d98787))
+* **api:** add IS_NEW_MERCHANT attribute to auth rules conditional authorization ([48b6bd5](https://github.com/lithic-com/lithic-ruby/commit/48b6bd5a7a5076b8e59b6b6f30730c4d1c706a0b))
+* support setting headers via env ([01b4c63](https://github.com/lithic-com/lithic-ruby/commit/01b4c634e91f47513e26619946ab010f5f1decec))
+
+
+### Bug Fixes
+
+* **api:** Allow null values for optional enum and object fields in schema validation ([9ebb823](https://github.com/lithic-com/lithic-ruby/commit/9ebb8239e22dc3f680560918ac628af6707a3114))
+
+
+### Chores
+
+* **internal:** codegen related update ([7da8cdf](https://github.com/lithic-com/lithic-ruby/commit/7da8cdf24a46edc1a7cdd8764275542590c729a7))
+* **internal:** more robust bootstrap script ([b03a0eb](https://github.com/lithic-com/lithic-ruby/commit/b03a0eb40e63ea3c40ffe90eaa30796a7722feac))
+
+
+### Documentation
+
+* **api:** update exp_month/exp_year descriptions in card create/renew params ([02db7be](https://github.com/lithic-com/lithic-ruby/commit/02db7be84225c5782bdcf2de90c55890bd2b0358))
+* **types:** clarify event_tokens and transaction_token fields in SettlementDetail ([5eacf6f](https://github.com/lithic-com/lithic-ruby/commit/5eacf6f69073956549ff4d3e2141d56650dd0ba7))
+
 ## 0.12.0 (2026-04-20)
 
 Full Changelog: [v0.11.0...v0.12.0](https://github.com/lithic-com/lithic-ruby/compare/v0.11.0...v0.12.0)

diff --git a/Gemfile.lock b/Gemfile.lock
@@ -11,7 +11,7 @@ GIT
 PATH
   remote: .
   specs:
-    lithic (0.12.0)
+    lithic (0.13.0)
       cgi
       connection_pool
 
@@ -143,7 +143,7 @@ GEM
       rexml (>= 3.2.6)
       sorbet-static-and-runtime (>= 0.5.10187)
       thor (>= 0.19.2)
-    standardwebhooks (1.0.1)
+    standardwebhooks (1.1.0)
     steep (1.10.0)
       activesupport (>= 5.1)
       concurrent-ruby (>= 1.1.10)

diff --git a/README.md b/README.md
@@ -24,7 +24,7 @@ To use this gem, install via Bundler by adding the following to your application
 <!-- x-release-please-start-version -->
 
 ```ruby
-gem "lithic", "~> 0.12.0"
+gem "lithic", "~> 0.13.0"
 ```
 
 <!-- x-release-please-end -->

diff --git a/lib/lithic.rb b/lib/lithic.rb
@@ -57,6 +57,7 @@
 require_relative "lithic/internal/single_page"
 require_relative "lithic/models/merchant"
 require_relative "lithic/models/transaction"
+require_relative "lithic/models/auth_rules/velocity_limit_filters"
 require_relative "lithic/models/auth_rules/v2/backtest_results"
 require_relative "lithic/models/book_transfer_response"
 require_relative "lithic/models/non_pci_card"
@@ -118,18 +119,21 @@
 require_relative "lithic/models/auth_rules/auth_rule_condition"
 require_relative "lithic/models/auth_rules/auth_rule_version"
 require_relative "lithic/models/auth_rules/backtest_stats"
+require_relative "lithic/models/auth_rules/card_transaction_update_action"
 require_relative "lithic/models/auth_rules/conditional_3ds_action_parameters"
 require_relative "lithic/models/auth_rules/conditional_ach_action_parameters"
 require_relative "lithic/models/auth_rules/conditional_attribute"
 require_relative "lithic/models/auth_rules/conditional_authorization_action_parameters"
 require_relative "lithic/models/auth_rules/conditional_block_parameters"
+require_relative "lithic/models/auth_rules/conditional_card_transaction_update_action_parameters"
 require_relative "lithic/models/auth_rules/conditional_operation"
 require_relative "lithic/models/auth_rules/conditional_tokenization_action_parameters"
 require_relative "lithic/models/auth_rules/conditional_value"
 require_relative "lithic/models/auth_rules/event_stream"
 require_relative "lithic/models/auth_rules/merchant_lock_parameters"
 require_relative "lithic/models/auth_rules/report_stats"
 require_relative "lithic/models/auth_rules/rule_feature"
+require_relative "lithic/models/auth_rules/spend_velocity_filters"
 require_relative "lithic/models/auth_rules/typescript_code_parameters"
 require_relative "lithic/models/auth_rules/v2/backtest_create_params"
 require_relative "lithic/models/auth_rules/v2/backtest_create_response"
@@ -149,7 +153,6 @@
 require_relative "lithic/models/auth_rules/v2_retrieve_report_params"
 require_relative "lithic/models/auth_rules/v2_retrieve_report_response"
 require_relative "lithic/models/auth_rules/v2_update_params"
-require_relative "lithic/models/auth_rules/velocity_limit_filters"
 require_relative "lithic/models/auth_rules/velocity_limit_params"
 require_relative "lithic/models/auth_rules/velocity_limit_period"
 require_relative "lithic/models/auth_rules_backtest_report_created_webhook_event"

diff --git a/lib/lithic/client.rb b/lib/lithic/client.rb
@@ -190,6 +190,19 @@ def initialize(
         raise ArgumentError.new("api_key is required, and can be set via environ: \"LITHIC_API_KEY\"")
       end
 
+      headers = {}
+      custom_headers_env = ENV["LITHIC_CUSTOM_HEADERS"]
+      unless custom_headers_env.nil?
+        parsed = {}
+        custom_headers_env.split("\n").each do |line|
+          colon = line.index(":")
+          unless colon.nil?
+            parsed[line[0...colon].strip] = line[(colon + 1)..].strip
+          end
+        end
+        headers = parsed.merge(headers)
+      end
+
       @api_key = api_key.to_s
       @webhook_secret = webhook_secret&.to_s
 
@@ -198,7 +211,8 @@ def initialize(
         timeout: timeout,
         max_retries: max_retries,
         initial_retry_delay: initial_retry_delay,
-        max_retry_delay: max_retry_delay
+        max_retry_delay: max_retry_delay,
+        headers: headers
       )
 
       @accounts = Lithic::Resources::Accounts.new(client: self)

diff --git a/lib/lithic/models/account.rb b/lib/lithic/models/account.rb
@@ -102,7 +102,7 @@ class Account < Lithic::Internal::Type::BaseModel
       #     particular reason.
       #
       #   @return [Symbol, Lithic::Models::Account::Substatus, nil]
-      optional :substatus, enum: -> { Lithic::Account::Substatus }
+      optional :substatus, enum: -> { Lithic::Account::Substatus }, nil?: true
 
       # @!attribute verification_address
       #   @deprecated
@@ -130,7 +130,7 @@ class Account < Lithic::Internal::Type::BaseModel
       #
       #   @param comment [String] Additional context or information related to the account.
       #
-      #   @param substatus [Symbol, Lithic::Models::Account::Substatus] Account state substatus values:
+      #   @param substatus [Symbol, Lithic::Models::Account::Substatus, nil] Account state substatus values:
       #
       #   @param verification_address [Lithic::Models::Account::VerificationAddress]
 

diff --git a/lib/lithic/models/account_holder_simulate_enrollment_review_response.rb b/lib/lithic/models/account_holder_simulate_enrollment_review_response.rb
@@ -75,12 +75,13 @@ class AccountHolderSimulateEnrollmentReviewResponse < Lithic::Internal::Type::Ba
       optional :email, String
 
       # @!attribute exemption_type
-      #   The type of KYC exemption for a KYC-Exempt Account Holder. "None" if the account
+      #   The type of KYC exemption for a KYC-Exempt Account Holder. `null` if the account
       #   holder is not KYC-Exempt.
       #
       #   @return [Symbol, Lithic::Models::AccountHolderSimulateEnrollmentReviewResponse::ExemptionType, nil]
       optional :exemption_type,
-               enum: -> { Lithic::Models::AccountHolderSimulateEnrollmentReviewResponse::ExemptionType }
+               enum: -> { Lithic::Models::AccountHolderSimulateEnrollmentReviewResponse::ExemptionType },
+               nil?: true
 
       # @!attribute external_id
       #   Customer-provided token that indicates a relationship with an object outside of
@@ -188,7 +189,7 @@ class AccountHolderSimulateEnrollmentReviewResponse < Lithic::Internal::Type::Ba
       #
       #   @param email [String] (Deprecated. Use control_person.email when user_type == "BUSINESS".
       #
-      #   @param exemption_type [Symbol, Lithic::Models::AccountHolderSimulateEnrollmentReviewResponse::ExemptionType] The type of KYC exemption for a KYC-Exempt Account Holder. "None" if the account
+      #   @param exemption_type [Symbol, Lithic::Models::AccountHolderSimulateEnrollmentReviewResponse::ExemptionType, nil] The type of KYC exemption for a KYC-Exempt Account Holder. `null` if the account
       #
       #   @param external_id [String] Customer-provided token that indicates a relationship with an object outside of
       #
@@ -465,7 +466,7 @@ class Address < Lithic::Internal::Type::BaseModel
         end
       end
 
-      # The type of KYC exemption for a KYC-Exempt Account Holder. "None" if the account
+      # The type of KYC exemption for a KYC-Exempt Account Holder. `null` if the account
       # holder is not KYC-Exempt.
       #
       # @see Lithic::Models::AccountHolderSimulateEnrollmentReviewResponse#exemption_type

diff --git a/lib/lithic/models/account_holder_update_response.rb b/lib/lithic/models/account_holder_update_response.rb
@@ -82,7 +82,7 @@ class KYBKYCPatchResponse < Lithic::Internal::Type::BaseModel
         optional :email, String
 
         # @!attribute exemption_type
-        #   The type of KYC exemption for a KYC-Exempt Account Holder. "None" if the account
+        #   The type of KYC exemption for a KYC-Exempt Account Holder. `null` if the account
         #   holder is not KYC-Exempt.
         #
         #   @return [Symbol, Lithic::Models::AccountHolderUpdateResponse::KYBKYCPatchResponse::ExemptionType, nil]
@@ -196,7 +196,7 @@ class KYBKYCPatchResponse < Lithic::Internal::Type::BaseModel
         #
         #   @param email [String] (Deprecated. Use control_person.email when user_type == "BUSINESS".
         #
-        #   @param exemption_type [Symbol, Lithic::Models::AccountHolderUpdateResponse::KYBKYCPatchResponse::ExemptionType] The type of KYC exemption for a KYC-Exempt Account Holder. "None" if the account
+        #   @param exemption_type [Symbol, Lithic::Models::AccountHolderUpdateResponse::KYBKYCPatchResponse::ExemptionType] The type of KYC exemption for a KYC-Exempt Account Holder. `null` if the account
         #
         #   @param external_id [String] Customer-provided token that indicates a relationship with an object outside of
         #
@@ -473,7 +473,7 @@ class Address < Lithic::Internal::Type::BaseModel
           end
         end
 
-        # The type of KYC exemption for a KYC-Exempt Account Holder. "None" if the account
+        # The type of KYC exemption for a KYC-Exempt Account Holder. `null` if the account
         # holder is not KYC-Exempt.
         #
         # @see Lithic::Models::AccountHolderUpdateResponse::KYBKYCPatchResponse#exemption_type

diff --git a/lib/lithic/models/account_update_params.rb b/lib/lithic/models/account_update_params.rb
@@ -80,7 +80,7 @@ class AccountUpdateParams < Lithic::Internal::Type::BaseModel
       #     particular reason.
       #
       #   @return [Symbol, Lithic::Models::AccountUpdateParams::Substatus, nil]
-      optional :substatus, enum: -> { Lithic::AccountUpdateParams::Substatus }
+      optional :substatus, enum: -> { Lithic::AccountUpdateParams::Substatus }, nil?: true
 
       # @!attribute verification_address
       #   @deprecated
@@ -109,7 +109,7 @@ class AccountUpdateParams < Lithic::Internal::Type::BaseModel
       #
       #   @param state [Symbol, Lithic::Models::AccountUpdateParams::State] Account states.
       #
-      #   @param substatus [Symbol, Lithic::Models::AccountUpdateParams::Substatus] Account state substatus values:
+      #   @param substatus [Symbol, Lithic::Models::AccountUpdateParams::Substatus, nil] Account state substatus values:
       #
       #   @param verification_address [Lithic::Models::AccountUpdateParams::VerificationAddress] Address used during Address Verification Service (AVS) checks during transaction
       #