diff --git a/lib/valkyrie/sequel/persister.rb b/lib/valkyrie/sequel/persister.rb
index 5149f96..3df6dad 100644
--- a/lib/valkyrie/sequel/persister.rb
+++ b/lib/valkyrie/sequel/persister.rb
@@ -8,9 +8,9 @@ def initialize(adapter:)
       @adapter = adapter
     end
 
-    def save(resource:)
+    def save(resource:, external_resource: false)
       object_attributes = resource_factory.from_resource(resource: resource)
-      output = create_or_update(resource: resource, attributes: object_attributes)
+      output = create_or_update(resource: resource, attributes: object_attributes, external_resource: external_resource)
       resource_factory.to_resource(object: output)
     end
 
@@ -121,11 +121,18 @@ def wipe!
 
     private
 
-    def create_or_update(resource:, attributes:)
+    def create_or_update(resource:, attributes:, external_resource:)
       attributes[:updated_at] = Time.now.utc
       attributes[:created_at] ||= Time.now.utc
-      return create(resource: resource, attributes: attributes) unless resource.persisted? && !exists?(id: attributes[:id])
-      update(resource: resource, attributes: attributes)
+      if exists?(id: attributes[:id])
+        update(resource: resource, attributes: attributes)
+      else
+        if !external_resource && resource.persisted?
+          # This resource has been deleted in the meantime, error.
+          raise Valkyrie::Persistence::ObjectNotFoundError, "The object #{resource.id} is previously persisted but not found at save time." unless exists?(id: attributes[:id])
+        end
+        create(resource: resource, attributes: attributes)
+      end
     end
 
     def create(resource:, attributes:)
@@ -146,7 +153,7 @@ def update(resource:, attributes:)
     end
 
     def exists?(id:)
-      resources.select(1).first(id: id).nil?
+      !resources.select(1).first(id: id).nil?
     end
   end
 end
diff --git a/lib/valkyrie/sequel/version.rb b/lib/valkyrie/sequel/version.rb
index c02dffb..3cb4166 100644
--- a/lib/valkyrie/sequel/version.rb
+++ b/lib/valkyrie/sequel/version.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 module Valkyrie
   module Sequel
-    VERSION = "2.2.1"
+    VERSION = "3.0.0.beta1"
   end
 end
diff --git a/valkyrie-sequel.gemspec b/valkyrie-sequel.gemspec
index 1f81a87..03d9919 100644
--- a/valkyrie-sequel.gemspec
+++ b/valkyrie-sequel.gemspec
@@ -22,7 +22,7 @@ Gem::Specification.new do |spec|
 
   spec.add_dependency "sequel", "~> 5.0"
   spec.add_dependency "sequel_pg", "~> 1.0"
-  spec.add_dependency "valkyrie", ">= 2.1", "< 2.3"
+  spec.add_dependency "valkyrie", ">= 3.0.0.beta1"
   spec.add_dependency "oj", "~> 3.0"
   spec.add_development_dependency "bundler", "~> 2.0"
   spec.add_development_dependency "rake"