diff --git a/Rakefile b/Rakefile
index df67edc6..59c589eb 100644
--- a/Rakefile
+++ b/Rakefile
@@ -40,8 +40,8 @@ namespace :db do
     apartment_db_file = 'spec/config/database.yml'
     rails_db_file = 'spec/dummy/config/database.yml'
 
-    FileUtils.copy(apartment_db_file + '.sample', apartment_db_file, :verbose => true) unless File.exists?(apartment_db_file)
-    FileUtils.copy(rails_db_file + '.sample', rails_db_file, :verbose => true)         unless File.exists?(rails_db_file)
+    FileUtils.copy(apartment_db_file + '.sample', apartment_db_file, :verbose => true) unless File.exist?(apartment_db_file)
+    FileUtils.copy(rails_db_file + '.sample', rails_db_file, :verbose => true)         unless File.exist?(rails_db_file)
   end
 end
 
diff --git a/apartment.gemspec b/apartment.gemspec
index eb59070f..73f7854c 100644
--- a/apartment.gemspec
+++ b/apartment.gemspec
@@ -19,7 +19,7 @@ Gem::Specification.new do |s|
   s.licenses = ["MIT"]
 
   # must be >= 3.1.2 due to bug in prepared_statements
-  s.add_dependency 'activerecord',    '>= 3.1.2', '< 6.1'
+  s.add_dependency 'activerecord',    '>= 3.1.2', '<= 6.1.7.6'
   s.add_dependency 'rack',            '>= 1.3.6'
   s.add_dependency 'public_suffix',   '>= 2'
   s.add_dependency 'parallel',        '>= 0.7.1'
diff --git a/lib/apartment/adapters/abstract_adapter.rb b/lib/apartment/adapters/abstract_adapter.rb
index 78b844b9..c7e2f0d0 100644
--- a/lib/apartment/adapters/abstract_adapter.rb
+++ b/lib/apartment/adapters/abstract_adapter.rb
@@ -209,7 +209,7 @@ def multi_tenantify_with_tenant_db_name(config, tenant)
       #   Load a file or raise error if it doesn't exists
       #
       def load_or_raise(file)
-        if File.exists?(file)
+        if File.exist?(file)
           load(file)
         else
           raise FileNotFound, "#{file} doesn't exist yet"
diff --git a/lib/apartment/adapters/sqlite3_adapter.rb b/lib/apartment/adapters/sqlite3_adapter.rb
index dff5a21b..eb0469b0 100644
--- a/lib/apartment/adapters/sqlite3_adapter.rb
+++ b/lib/apartment/adapters/sqlite3_adapter.rb
@@ -17,7 +17,7 @@ def initialize(config)
 
       def drop(tenant)
         raise TenantNotFound,
-          "The tenant #{environmentify(tenant)} cannot be found." unless File.exists?(database_file(tenant))
+          "The tenant #{environmentify(tenant)} cannot be found." unless File.exist?(database_file(tenant))
 
         File.delete(database_file(tenant))
       end
@@ -30,14 +30,14 @@ def current
 
       def connect_to_new(tenant)
         raise TenantNotFound,
-          "The tenant #{environmentify(tenant)} cannot be found." unless File.exists?(database_file(tenant))
+          "The tenant #{environmentify(tenant)} cannot be found." unless File.exist?(database_file(tenant))
 
         super database_file(tenant)
       end
 
       def create_tenant(tenant)
         raise TenantExists,
-          "The tenant #{environmentify(tenant)} already exists." if File.exists?(database_file(tenant))
+          "The tenant #{environmentify(tenant)} already exists." if File.exist?(database_file(tenant))
 
         begin
           f = File.new(database_file(tenant), File::CREAT)
diff --git a/spec/adapters/sqlite3_adapter_spec.rb b/spec/adapters/sqlite3_adapter_spec.rb
index 55004952..fcb6198b 100644
--- a/spec/adapters/sqlite3_adapter_spec.rb
+++ b/spec/adapters/sqlite3_adapter_spec.rb
@@ -40,7 +40,7 @@ def tenant_names
         it "should create a new database" do
           subject.create db_name
 
-          expect(File.exists?("#{default_dir}/#{Rails.env}_#{db_name}.sqlite3")).to eq true
+          expect(File.exist?("#{default_dir}/#{Rails.env}_#{db_name}.sqlite3")).to eq true
         end
       end
 
@@ -55,7 +55,7 @@ def tenant_names
         it "should create a new database" do
           subject.create db_name
 
-          expect(File.exists?("#{default_dir}/#{db_name}.sqlite3")).to eq true
+          expect(File.exist?("#{default_dir}/#{db_name}.sqlite3")).to eq true
         end
       end
 
@@ -73,7 +73,7 @@ def tenant_names
         it "should create a new database" do
           subject.create db_name
 
-          expect(File.exists?("#{default_dir}/#{db_name}_#{Rails.env}.sqlite3")).to eq true
+          expect(File.exist?("#{default_dir}/#{db_name}_#{Rails.env}.sqlite3")).to eq true
         end
       end