diff --git a/misc/paas/heroku/Gemfile.local b/misc/paas/heroku/Gemfile.local
index ef0c4faad..26541ce69 100644
--- a/misc/paas/heroku/Gemfile.local
+++ b/misc/paas/heroku/Gemfile.local
@@ -1,4 +1,4 @@
-ruby '~> 2.6.5'
+ruby '~> 2.7.0'
 gem 'puma', require: false
 gem 'tdiary-io-mongodb', git: 'https://github.com/tdiary/tdiary-io-mongodb.git'
 gem 'tdiary-contrib', git: 'https://github.com/tdiary/tdiary-contrib.git'
diff --git a/misc/paas/heroku/Gemfile.lock b/misc/paas/heroku/Gemfile.lock
index f464dd711..2f5ff3300 100644
--- a/misc/paas/heroku/Gemfile.lock
+++ b/misc/paas/heroku/Gemfile.lock
@@ -1,6 +1,6 @@
 GIT
   remote: https://github.com/tdiary/tdiary-contrib.git
-  revision: 78745f64058bb1da7ce3152ac65fb8289fa0d4c8
+  revision: 4829dffbafccbd9561e5bbadc325b89a891399e0
   specs:
     tdiary-contrib (5.1.0)
       pushbullet_ruby
@@ -31,7 +31,7 @@ GEM
       public_suffix (>= 2.0.2, < 5.0)
     bson (4.7.0)
     byebug (11.0.1)
-    capybara (3.29.0)
+    capybara (3.30.0)
       addressable
       mini_mime (>= 0.1.3)
       nokogiri (~> 1.8)
@@ -44,12 +44,12 @@ GEM
     commonmarker (0.20.2)
       ruby-enum (~> 0.5)
     concurrent-ruby (1.1.5)
-    coveralls (0.8.23)
-      json (>= 1.8, < 3)
-      simplecov (~> 0.16.1)
-      term-ansicolor (~> 1.3)
-      thor (>= 0.19.4, < 2.0)
-      tins (~> 1.6)
+    coveralls (0.7.2)
+      multi_json (~> 1.3)
+      rest-client (= 1.6.7)
+      simplecov (>= 0.7)
+      term-ansicolor (= 1.2.2)
+      thor (= 0.18.1)
     dalli (2.7.10)
     debase (0.2.4.1)
       debase-ruby_core_source (>= 0.10.2)
@@ -90,6 +90,7 @@ GEM
     mongoid (7.0.5)
       activemodel (>= 5.1, < 6.1)
       mongo (>= 2.5.1, < 3.0.0)
+    multi_json (1.14.1)
     multipart-post (2.1.1)
     nio4r (2.5.2)
     nokogiri (1.10.7)
@@ -131,6 +132,8 @@ GEM
     rdtool (0.6.38)
     redcarpet (3.5.0)
     regexp_parser (1.6.0)
+    rest-client (1.6.7)
+      mime-types (>= 1.16)
     rspec (3.9.0)
       rspec-core (~> 3.9.0)
       rspec-expectations (~> 3.9.0)
@@ -156,7 +159,7 @@ GEM
       childprocess (>= 0.5, < 4.0)
       rubyzip (>= 1.2.2)
     sequel (5.27.0)
-    simplecov (0.16.1)
+    simplecov (0.17.1)
       docile (~> 1.1)
       json (>= 1.8, < 3)
       simplecov-html (~> 0.10.0)
@@ -177,17 +180,17 @@ GEM
       twitter-text (>= 2.0)
     tdiary-style-rd (0.0.3)
       rdtool
-    term-ansicolor (1.7.1)
-      tins (~> 1.0)
+    term-ansicolor (1.2.2)
+      tins (~> 0.8)
     test-unit (3.3.4)
       power_assert
-    thor (1.0.1)
+    thor (0.18.1)
     thread_safe (0.3.6)
-    tins (1.22.2)
+    tins (0.13.2)
     twitter-text (3.0.0)
       idn-ruby
       unf (~> 0.1.0)
-    tzinfo (1.2.5)
+    tzinfo (1.2.6)
       thread_safe (~> 0.1)
     unf (0.1.4)
       unf_ext
@@ -235,7 +238,7 @@ DEPENDENCIES
   test-unit
 
 RUBY VERSION
-   ruby 2.6.5p114
+   ruby 2.7.0p0
 
 BUNDLED WITH
-   2.0.2
+   2.1.2