diff --git a/spec/letsencrypt_spec.rb b/spec/letsencrypt_spec.rb
index a4d288a..c32ad7f 100644
--- a/spec/letsencrypt_spec.rb
+++ b/spec/letsencrypt_spec.rb
@@ -6,7 +6,7 @@
   let(:tempfile) { Tempfile.new }
   let(:key) { OpenSSL::PKey::RSA.new(2048) }
 
-  before :each do
+  before do
     LetsEncrypt.class_eval do
       @private_key = nil
       @endpoint = nil
@@ -16,38 +16,37 @@
   end
 
   describe '#generate_private_key' do
-    it 'create a new private key' do
-      key = LetsEncrypt.generate_private_key
-      expect(LetsEncrypt.private_key.to_s).to eq(key.to_s)
-    end
+    let!(:key) { LetsEncrypt.generate_private_key }
+
+    it { expect(LetsEncrypt.private_key.to_s).to eq(key.to_s) }
   end
 
   describe '#register' do
     let(:acme_client) { double(Acme::Client) }
     let(:acme_account) { double }
 
-    it 'register new account to Let\'s Encrypt' do
+    before do
       tempfile.write(key.to_s)
       tempfile.rewind
 
       allow(LetsEncrypt).to receive(:client).and_return(acme_client)
       allow(acme_client).to receive(:new_account).and_return(acme_account)
       allow(acme_account).to receive(:kid).and_return('')
-
-      LetsEncrypt.register('example@example.com')
     end
+
+    it { expect(LetsEncrypt.register('example@example.com')).to be_truthy }
   end
 
   describe 'certificate_model' do
     before do
       stub_const('OtherModel', Class.new(LetsEncrypt::Certificate))
-
       LetsEncrypt.config.certificate_model = 'OtherModel'
+
       allow(LetsEncrypt).to receive(:certificate_model) { LetsEncrypt.config.certificate_model.constantize }
     end
+
     after { LetsEncrypt.config.certificate_model = 'LetsEncrypt::Certificate' }
-    it 'set the certificate_model to customize model' do
-      expect(LetsEncrypt.certificate_model).to eq('OtherModel'.constantize)
-    end
+
+    it { expect(LetsEncrypt).to have_attributes(certificate_model: OtherModel) }
   end
 end