diff --git a/lib/fmrest/spyke/model/attributes.rb b/lib/fmrest/spyke/model/attributes.rb
index 9b81cc6..35822be 100644
--- a/lib/fmrest/spyke/model/attributes.rb
+++ b/lib/fmrest/spyke/model/attributes.rb
@@ -22,7 +22,13 @@ module Attributes
           # when calling ActiveModels' define_attribute_method, otherwise it
           # will define an `attribute` method which overrides the one provided
           # by Spyke
-          self.attribute_method_matchers.shift
+          if respond_to? :attribute_method_patterns
+            # ActiveModel >= 7.1
+            attribute_method_patterns.shift
+          else
+            # ActiveModel < 7.1
+            attribute_method_matchers.shift
+          end
 
           # Keep track of attribute mappings so we can get the FM field names
           # for changed attributes
diff --git a/spec/spyke/model/attributes_spec.rb b/spec/spyke/model/attributes_spec.rb
index 69bb76c..bc249ab 100644
--- a/spec/spyke/model/attributes_spec.rb
+++ b/spec/spyke/model/attributes_spec.rb
@@ -24,9 +24,21 @@
   # TODO: Rewrite this spec to be less dependent on ActiveModel's internals
   describe ".attribute_method_matchers" do
     it "doesn't include a plain entry" do
-      matcher = test_class.attribute_method_matchers.first
-      # ActiveModel 6 uses .target, while ActiveModel <= 5 uses method_missing_target
-      target = matcher.respond_to?(:target) ? matcher.target : matcher.method_missing_target
+      matcher = if test_class.respond_to?(:attribute_method_patterns)
+                  test_class.attribute_method_patterns.first
+                else
+                  test_class.attribute_method_matchers.first
+                end
+      target = if matcher.respond_to?(:proxy_target)
+                 # ActiveModel >= 7.1
+                 matcher.proxy_target
+               elsif matcher.respond_to?(:target)
+                 # ActiveModel >= 6, < 7.1
+                 matcher.target
+               else
+                 # ActiveModel <= 5
+                 matcher.method_missing_target
+               end
       expect(target).to_not eq("attribute")
     end
   end