diff --git a/spec/models/fluentd/agent_spec.rb b/spec/models/fluentd/agent_spec.rb
index 6c46dd1..01bcd32 100644
--- a/spec/models/fluentd/agent_spec.rb
+++ b/spec/models/fluentd/agent_spec.rb
@@ -29,7 +29,7 @@ describe Fluentd::Agent do
     end
 
     describe "#recent_errors" do
-      before { instance.stub(:log_file).and_return { logfile } }
+      before { instance.stub(:log_file).and_return(logfile) }
 
       context "have 0 error log" do
         let(:logfile) { File.expand_path("./spec/support/fixtures/error0.log", Rails.root) }
@@ -88,14 +88,14 @@ describe Fluentd::Agent do
     end
 
     describe "#start" do
-      before { instance.stub(:running?).and_return { running } }
+      before { instance.stub(:running?).and_return(running) }
 
       context "running" do
         let(:running) { true }
 
         subject { instance.start }
 
-        it { should be_true }
+        it { should be_truthy }
       end
 
       context "not running" do
@@ -104,52 +104,52 @@ describe Fluentd::Agent do
         subject { instance.start }
 
         before do
-          instance.stub(:actual_start).and_return { start_result }
+          instance.stub(:actual_start).and_return(start_result)
         end
 
         context "actual start success" do
           let(:start_result) { true }
-          it { should be_true }
+          it { should be_truthy }
         end
 
         context "actual start failed" do
           let(:start_result) { false }
-          it { should be_false }
+          it { should be_falsy }
         end
       end
     end
 
     describe "#stop" do
-      before { instance.stub(:running?).and_return { running } }
+      before { instance.stub(:running?).and_return(running) }
 
       subject { instance.stop }
 
       context "running" do
         let(:running) { true }
 
-        before { instance.stub(:actual_stop).and_return { stop_result } }
+        before { instance.stub(:actual_stop).and_return(stop_result) }
 
         context "actual stop success" do
           let(:stop_result) { true }
-          it { should be_true }
+          it { should be_truthy }
         end
 
         context "actual stop failed" do
           let(:stop_result) { false }
-          it { should be_false }
+          it { should be_falsy }
         end
       end
 
       context "not running" do
         let(:running) { false }
 
-        it { should be_true }
+        it { should be_truthy }
       end
     end
 
     describe "#restart" do
-      before { instance.stub(:stop).and_return { stop_result } }
-      before { instance.stub(:start).and_return { start_result } }
+      before { instance.stub(:stop).and_return(stop_result) }
+      before { instance.stub(:start).and_return(start_result) }
       subject { instance.restart }
 
       describe "return true only if #stop and #start success" do
@@ -158,12 +158,12 @@ describe Fluentd::Agent do
 
           context" #start success" do
             let(:start_result) { true } 
-            it { should be_true }
+            it { should be_truthy }
           end
 
           context" #start fail" do
             let(:start_result) { false } 
-            it { should be_false }
+            it { should be_falsy }
           end
         end
 
@@ -172,12 +172,12 @@ describe Fluentd::Agent do
 
           context" #start success" do
             let(:start_result) { true } 
-            it { should be_false }
+            it { should be_falsy }
           end
 
           context" #start fail" do
             let(:start_result) { false } 
-            it { should be_false }
+            it { should be_falsy }
           end
         end
       end
diff --git a/spec/models/fluentd_spec.rb b/spec/models/fluentd_spec.rb
index 75ce9b0..7d66bd6 100644
--- a/spec/models/fluentd_spec.rb
+++ b/spec/models/fluentd_spec.rb
@@ -154,12 +154,12 @@ describe Fluentd do
 
     context "doesn't exists" do
       before { File.unlink(config_file) if File.exist?(config_file) }
-      it { File.exist?(subject).should be_true }
+      it { File.exist?(subject).should be_truthy }
     end
 
     context "already exists" do
       before { FileUtils.touch(config_file) }
-      it { File.exist?(subject).should be_true }
+      it { File.exist?(subject).should be_truthy }
     end
   end
 end
diff --git a/spec/models/login_token_spec.rb b/spec/models/login_token_spec.rb
index 87c7c61..b1d7e57 100644
--- a/spec/models/login_token_spec.rb
+++ b/spec/models/login_token_spec.rb
@@ -17,13 +17,13 @@ describe LoginToken do
     describe "#active" do
       subject { LoginToken.active }
       it { subject.count.should == active }
-      it { subject.all?{|t| t.expired_at > Time.now}.should be_true }
+      it { subject.all?{|t| t.expired_at > Time.now}.should be_truthy }
     end
 
     describe "#inactive" do
       subject { LoginToken.inactive }
       it { subject.count.should == inactive }
-      it { subject.all?{|t| t.expired_at <= Time.now}.should be_true }
+      it { subject.all?{|t| t.expired_at <= Time.now}.should be_truthy }
     end
   end
 end
diff --git a/spec/models/plugin_spec.rb b/spec/models/plugin_spec.rb
index 3f60678..6e556db 100644
--- a/spec/models/plugin_spec.rb
+++ b/spec/models/plugin_spec.rb
@@ -4,7 +4,7 @@ describe Plugin do
   let(:plugin) { build(:plugin) }
 
   before do
-    Plugin.stub(:gemfile_path).and_return { Rails.root + "tmp/fluentd-ui-test-gemfile.plugins" }
+    Plugin.stub(:gemfile_path).and_return(Rails.root + "tmp/fluentd-ui-test-gemfile.plugins" )
   end
 
   after do
@@ -51,8 +51,8 @@ describe Plugin do
   describe "#install!" do
     describe "invoke fluent_gem" do
       after do
-        plugin.stub(:valid?).and_return { valid }
-        plugin.stub(:installed?).and_return { installed }
+        plugin.stub(:valid?).and_return(valid)
+        plugin.stub(:installed?).and_return(installed)
         plugin.install!
       end
 
@@ -86,7 +86,7 @@ describe Plugin do
     end
 
     context "system command error" do
-      before { plugin.should_receive(:system).and_return { false } }
+      before { plugin.should_receive(:system).and_return(false) }
       subject { expect { plugin.install! } }
 
       it "raise GemError" do
@@ -100,7 +100,7 @@ describe Plugin do
 
     describe "after install succeed" do
       before do
-        plugin.stub(:fluent_gem).and_return { true }
+        plugin.stub(:fluent_gem).and_return(true)
         plugin.install!
       end
 
@@ -113,7 +113,7 @@ describe Plugin do
     let(:installed_plugin) { build(:plugin, gem_name: "fluent-plugin-foobar") }
 
     before do
-      installed_plugin.stub(:fluent_gem).and_return { true }
+      installed_plugin.stub(:fluent_gem).and_return(true)
       installed_plugin.install!
       Plugin.pristine!
     end
@@ -132,7 +132,7 @@ describe Plugin do
     let(:target_version) { "1.2.0" }
 
     before do
-      Plugin.any_instance.stub(:fluent_gem).and_return { true } # NOTE: not `plugin.stub` because upgrade! creates new Plugin instance internally
+      Plugin.any_instance.stub(:fluent_gem).and_return(true) # NOTE: not `plugin.stub` because upgrade! creates new Plugin instance internally
       installed_plugin.install!
       Plugin.pristine!
       installed_plugin.upgrade!(target_version)
@@ -145,7 +145,7 @@ describe Plugin do
 
   describe ".installed" do
     before do
-      plugin.stub(:fluent_gem).and_return { true }
+      plugin.stub(:fluent_gem).and_return(true)
       plugin.install!
     end
 
@@ -159,7 +159,7 @@ describe Plugin do
     let(:gem_version) { Gem::Version.new("1.0.0") }
 
     before do
-      plugin.stub(:installed_version).and_return { gem_version.to_s }
+      plugin.stub(:installed_version).and_return(gem_version.to_s)
       stub_request(:get, /rubygems.org/).to_return(body: JSON.dump(api_response))
     end
 
@@ -170,7 +170,7 @@ describe Plugin do
         [{number: gem_version.bump}, {number: gem_version}]
       end
 
-      it { subject.should be_false }
+      it { subject.should be_falsy }
     end
 
     context "unavailable updates" do
@@ -178,13 +178,13 @@ describe Plugin do
         [{number: gem_version}]
       end
 
-      it { subject.should be_true }
+      it { subject.should be_truthy }
     end
   end
 
   describe "#installed_version" do
     before do
-      Plugin.any_instance.stub(:fluent_gem).and_return { true } # NOTE: not `plugin.stub` because upgrade! creates new Plugin instance internally
+      Plugin.any_instance.stub(:fluent_gem).and_return(true) # NOTE: not `plugin.stub` because upgrade! creates new Plugin instance internally
       plugin.install!
     end
 
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 897babc..82f09b3 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -55,6 +55,9 @@ RSpec.configure do |config|
   #     --seed 1234
   config.order = "random"
 
+  # rspec 2.99
+  config.infer_spec_type_from_file_location!
+
   config.before(:suite) do
     DatabaseCleaner.strategy = :transaction
     DatabaseCleaner.clean_with(:truncation)