diff --git a/.ruby-version b/.ruby-version
index 7bf4b6a..338a5b5 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-2.4.6
+2.6.6
diff --git a/HornsAndHooves-moribus.gemspec b/HornsAndHooves-moribus.gemspec
index 3be0985..f987fb2 100644
--- a/HornsAndHooves-moribus.gemspec
+++ b/HornsAndHooves-moribus.gemspec
@@ -27,5 +27,5 @@ Gem::Specification.new do |s|
   s.add_development_dependency "rake"
   s.add_development_dependency "rspec"
   s.add_development_dependency "rspec-rails"
-  s.add_development_dependency "sqlite3", "~> 1.3.6"
+  s.add_development_dependency "sqlite3"
 end
diff --git a/lib/moribus/aggregated_cache_behavior.rb b/lib/moribus/aggregated_cache_behavior.rb
index d5ecf58..1f1cca3 100644
--- a/lib/moribus/aggregated_cache_behavior.rb
+++ b/lib/moribus/aggregated_cache_behavior.rb
@@ -31,7 +31,7 @@ module AggregatedCacheBehavior
       class_attribute :aggregated_records_cache
       self.aggregated_records_cache = {}
 
-      after_save :cache_aggregated_record, :on => :create
+      after_commit :cache_aggregated_record, :on => :create
     end
 
     # Class methods for model that includes AggregatedCacheBehavior
diff --git a/spec/dummy/app/assets/config/manifest.js b/spec/dummy/app/assets/config/manifest.js
new file mode 100644
index 0000000..6277764
--- /dev/null
+++ b/spec/dummy/app/assets/config/manifest.js
@@ -0,0 +1,5 @@
+// Sprockets 4.0+ requires this file to define asset paths.
+
+//= link_tree ../images
+//= link_directory ../javascripts .js
+//= link_directory ../stylesheets .css
diff --git a/spec/moribus/aggregated_behavior_spec.rb b/spec/moribus/aggregated_behavior_spec.rb
index 4689e2e..77aeafa 100644
--- a/spec/moribus/aggregated_behavior_spec.rb
+++ b/spec/moribus/aggregated_behavior_spec.rb
@@ -93,7 +93,7 @@ class SpecCustomerFeature < MoribusSpecModel(feature_name: :string)
 
     it "looks up self and replaces id with existing on update" do
       name = SpecPersonName.create first_name: "Alice", last_name: "Smith"
-      name.update_attributes first_name: "John"
+      name.update! first_name: "John"
       expect(name.id).to eq @existing.id
     end
 
diff --git a/spec/moribus_spec.rb b/spec/moribus_spec.rb
index 87b5516..77b36da 100644
--- a/spec/moribus_spec.rb
+++ b/spec/moribus_spec.rb
@@ -128,7 +128,7 @@ class SpecCustomerEmail < MoribusSpecModel(spec_customer_id: :integer,
 
       suppress(Exception) do
         expect {
-          @info.update_attributes spec_customer_id: nil, spec_person_name_id: 2
+          @info.update! spec_customer_id: nil, spec_person_name_id: 2
         }.not_to change(SpecCustomerInfo, :count)
       end
 
@@ -155,25 +155,25 @@ class SpecCustomerEmail < MoribusSpecModel(spec_customer_id: :integer,
 
     it "creates a new current record if updated" do
       expect {
-        @info.update_attributes(spec_person_name_id: 2)
+        @info.update!(spec_person_name_id: 2)
       }.to change(SpecCustomerInfo, :count).by(1)
     end
 
     it "replaces itself with new id" do
       old_id = @info.id
-      @info.update_attributes(spec_person_name_id: 2)
+      @info.update!(spec_person_name_id: 2)
       expect(@info.id).not_to eq old_id
     end
 
     it "sets is_current record to false for superseded record" do
       old_id = @info.id
-      @info.update_attributes(spec_person_name_id: 2)
+      @info.update!(spec_person_name_id: 2)
       expect(SpecCustomerInfo.find(old_id).is_current).to eq false
     end
 
     it "sets previous_id to the id of the previous record" do
       old_id = @info.id
-      @info.update_attributes(spec_person_name_id: 2)
+      @info.update!(spec_person_name_id: 2)
       expect(@info.previous_id).to eq old_id
     end
 
@@ -191,7 +191,7 @@ class SpecCustomerEmail < MoribusSpecModel(spec_customer_id: :integer,
                                         status:        "unverified",
                                         is_current:    true
                                       )
-      expect{ email.update_attributes(status: "verified") }.not_to raise_error
+      expect{ email.update!(status: "verified") }.not_to raise_error
     end
 
     describe "updated_at and created_at" do
@@ -221,9 +221,9 @@ class SpecCustomerEmail < MoribusSpecModel(spec_customer_id: :integer,
       end
 
       it "raises a stale object error" do
-        @info1.update_attributes(spec_person_name_id: 3)
+        @info1.update!(spec_person_name_id: 3)
 
-        expect{ @info2.update_attributes(spec_person_name_id: 4) }.
+        expect{ @info2.update!(spec_person_name_id: 4) }.
           to raise_error(ActiveRecord::StaleObjectError,
                          /Attempted to update_current \(version #{@info2.lock_version}\) a stale object: SpecCustomerInfo\./)
       end
@@ -232,30 +232,30 @@ class SpecCustomerEmail < MoribusSpecModel(spec_customer_id: :integer,
         spec_customer_info = @customer.spec_customer_info
 
         expect {
-          spec_customer_info.update_attributes(spec_person_name_id: 3)
+          spec_customer_info.update!(spec_person_name_id: 3)
         }.to change { spec_customer_info.lock_version }.from(0).to(1)
 
         expect {
-          spec_customer_info.update_attributes(spec_person_name_id: 4)
+          spec_customer_info.update!(spec_person_name_id: 4)
         }.to change { spec_customer_info.lock_version }.from(1).to(2)
       end
 
       it "does not fail to update if a lock version growth is for any reason not monotonic" do
         spec_customer_info = @customer.spec_customer_info
 
-        spec_customer_info.update_attributes(spec_person_name_id: 3)
-        spec_customer_info.update_attributes(spec_person_name_id: 4)
+        spec_customer_info.update!(spec_person_name_id: 3)
+        spec_customer_info.update!(spec_person_name_id: 4)
 
         SpecCustomerInfo.where(spec_customer_id: @customer.id, lock_version: 1).delete_all
 
         expect {
-          spec_customer_info.update_attributes(spec_person_name_id: 5)
+          spec_customer_info.update!(spec_person_name_id: 5)
         }.to change { spec_customer_info.lock_version }.from(2).to(3)
       end
 
       it "does not fail if no locking_column is present" do
         email = SpecCustomerEmail.create(spec_customer_id: 1, email: "foo@bar.com")
-        expect{ email.update_attributes(email: "foo2@bar.com") }.not_to raise_error
+        expect{ email.update!(email: "foo2@bar.com") }.not_to raise_error
       end
 
       it "updates lock_version column based on parent relation" do
@@ -263,11 +263,11 @@ class SpecCustomerEmail < MoribusSpecModel(spec_customer_id: :integer,
         spec_customer_info = @customer.spec_customer_info
 
         expect {
-          spec_customer_info.update_attributes(spec_person_name_id: 3)
+          spec_customer_info.update!(spec_person_name_id: 3)
         }.to change { spec_customer_info.lock_version }.from(0).to(1)
 
         expect {
-          spec_customer_info.update_attributes(spec_customer: @other_customer)
+          spec_customer_info.update!(spec_customer: @other_customer)
         }.to change { spec_customer_info.lock_version }.from(1).to(0)
       end
 
@@ -282,10 +282,10 @@ class SpecCustomerEmail < MoribusSpecModel(spec_customer_id: :integer,
 
         expect( other_info_with_type.lock_version ).to eq 0
 
-        info_with_type.update_attributes(spec_status: :active)
+        info_with_type.update!(spec_status: :active)
         expect( info_with_type.lock_version ).to eq 1
 
-        info_with_type.update_attributes(spec_status: :inactive)
+        info_with_type.update!(spec_status: :inactive)
         expect( info_with_type.lock_version ).to eq 2
 
         expect( other_info_with_type.lock_version ).to eq 0