diff --git a/.ruby-version b/.ruby-version
index 437459c..73462a5 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-2.5.0
+2.5.1
diff --git a/Gemfile.lock b/Gemfile.lock
index 2763757..ecff3d2 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -7,40 +7,40 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    byebug (10.0.0)
-    castle-rb (3.4.2)
-    coveralls_reborn (0.10.0)
+    byebug (10.0.2)
+    castle-rb (3.5.0)
+    coveralls_reborn (0.12.0)
       json (~> 2.1)
-      simplecov (~> 0.15.1)
-      term-ansicolor (~> 1.3)
+      simplecov (~> 0.16.1)
+      term-ansicolor (~> 1.6)
       thor (~> 0.20.0)
-      tins (~> 1.6)
+      tins (~> 1.16)
     diff-lcs (1.3)
-    docile (1.1.5)
+    docile (1.3.1)
     json (2.1.0)
-    rake (12.3.0)
-    rspec (3.7.0)
-      rspec-core (~> 3.7.0)
-      rspec-expectations (~> 3.7.0)
-      rspec-mocks (~> 3.7.0)
-    rspec-core (3.7.1)
-      rspec-support (~> 3.7.0)
-    rspec-expectations (3.7.0)
+    rake (12.3.1)
+    rspec (3.8.0)
+      rspec-core (~> 3.8.0)
+      rspec-expectations (~> 3.8.0)
+      rspec-mocks (~> 3.8.0)
+    rspec-core (3.8.0)
+      rspec-support (~> 3.8.0)
+    rspec-expectations (3.8.2)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.7.0)
-    rspec-mocks (3.7.0)
+      rspec-support (~> 3.8.0)
+    rspec-mocks (3.8.0)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.7.0)
-    rspec-support (3.7.1)
-    simplecov (0.15.1)
-      docile (~> 1.1.0)
+      rspec-support (~> 3.8.0)
+    rspec-support (3.8.0)
+    simplecov (0.16.1)
+      docile (~> 1.1)
       json (>= 1.8, < 3)
       simplecov-html (~> 0.10.0)
     simplecov-html (0.10.2)
     term-ansicolor (1.6.0)
       tins (~> 1.0)
     thor (0.20.0)
-    tins (1.16.3)
+    tins (1.17.0)
 
 PLATFORMS
   ruby
@@ -53,4 +53,4 @@ DEPENDENCIES
   rspec
 
 BUNDLED WITH
-   1.16.1
+   1.16.6