diff --git a/sig/datadog/appsec/compressed_json.rbs b/sig/datadog/appsec/compressed_json.rbs
index ff1f5c5ac21..4a64b927881 100644
--- a/sig/datadog/appsec/compressed_json.rbs
+++ b/sig/datadog/appsec/compressed_json.rbs
@@ -3,7 +3,7 @@ module Datadog
     module CompressedJson
       MIN_SIZE_FOR_COMPRESSION: ::Integer
 
-      def self.dump: (untyped payload) -> ::String?
+      def self.dump: (any payload) -> ::String?
 
       def self.compress_and_encode: (::String payload) -> ::String?
     end
diff --git a/sig/datadog/core/encoding.rbs b/sig/datadog/core/encoding.rbs
index 9320f0fb615..b82915fdbd9 100644
--- a/sig/datadog/core/encoding.rbs
+++ b/sig/datadog/core/encoding.rbs
@@ -5,43 +5,43 @@ module Datadog
       # Encoder interface that provides the logic to encode traces and service
       # @abstract
       module Encoder
-        def content_type: () -> String
+        def content_type: () -> ::String
 
-        def encode: (untyped obj) -> String
+        def encode: (any obj) -> ::String
 
-        def join: (Array[untyped] encoded_data) -> String
+        def join: (::Array[::String] encoded_data) -> ::String
 
-        def decode: (String obj)-> untyped
+        def decode: (::String obj) -> any
       end
 
       # Encoder for the JSON format
       module JSONEncoder
         extend Encoder
 
-        CONTENT_TYPE: String
+        CONTENT_TYPE: ::String
 
-        def self?.content_type: () -> String
+        def self?.content_type: () -> ::String
 
-        def self?.encode: (untyped obj) -> String
+        def self?.encode: (any obj) -> ::String
 
-        def self?.join: (Array[untyped] encoded_data) -> String
+        def self?.join: (::Array[::String] encoded_data) -> ::String
 
-        def self?.decode: (String obj)-> untyped
+        def self?.decode: (::String obj) -> any
       end
 
       # Encoder for the Msgpack format
       module MsgpackEncoder
         extend Encoder
 
-        CONTENT_TYPE: String
+        CONTENT_TYPE: ::String
 
-        def self?.content_type: () -> String
+        def self?.content_type: () -> ::String
 
-        def self?.encode: (untyped obj) -> String
+        def self?.encode: (any obj) -> ::String
 
-        def self?.join: (Array[untyped] encoded_data) -> String
+        def self?.join: (::Array[::String] encoded_data) -> ::String
 
-        def self?.decode: (String obj)-> untyped
+        def self?.decode: (::String obj) -> any
       end
     end
   end
diff --git a/sig/datadog/core/tag_normalizer.rbs b/sig/datadog/core/tag_normalizer.rbs
index c6a92dccecf..3f24553a1c5 100644
--- a/sig/datadog/core/tag_normalizer.rbs
+++ b/sig/datadog/core/tag_normalizer.rbs
@@ -8,9 +8,9 @@ module Datadog
       MAX_PROCESS_VALUE_BYTE_SIZE: ::Integer
       VALID_ASCII_TAG: ::Regexp
 
-      def self.normalize: (untyped original_value, ?remove_digit_start_char: bool) -> ::String
+      def self.normalize: (any original_value, ?remove_digit_start_char: bool) -> ::String
 
-      def self.normalize_process_value: (untyped value) -> ::String
+      def self.normalize_process_value: (any value) -> ::String
     end
   end
 end
diff --git a/sig/datadog/core/utils/only_once.rbs b/sig/datadog/core/utils/only_once.rbs
index 354334c71e1..26d952fd22e 100644
--- a/sig/datadog/core/utils/only_once.rbs
+++ b/sig/datadog/core/utils/only_once.rbs
@@ -5,15 +5,15 @@ module Datadog
         @ran_once: bool
         @mutex: Thread::Mutex
 
-        def initialize: () -> untyped
+        def initialize: () -> void
 
         def run: () { () -> untyped } -> untyped
 
-        def ran?: () -> untyped
+        def ran?: () -> bool
 
         private
 
-        def reset_ran_once_state_for_tests: () -> untyped
+        def reset_ran_once_state_for_tests: () -> void
       end
     end
   end
diff --git a/sig/datadog/core/utils/sequence.rbs b/sig/datadog/core/utils/sequence.rbs
index 3c224a9c1f9..c0faa9d2cff 100644
--- a/sig/datadog/core/utils/sequence.rbs
+++ b/sig/datadog/core/utils/sequence.rbs
@@ -6,9 +6,9 @@ module Datadog
         @current: ::Integer
         @next_item: (^(::Integer) -> ::Integer)?
 
-        def initialize: (?::Integer seed) ?{ (::Integer) -> ::Integer } -> untyped
+        def initialize: (?::Integer seed) ?{ (::Integer) -> ::Integer } -> void
 
-        def next: () -> untyped
+        def next: () -> ::Integer
 
         def reset!: () -> void
       end