diff --git a/Gemfile.lock b/Gemfile.lock
index a697784..fdac44a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -2,9 +2,8 @@ GEM
   remote: https://rubygems.org/
   specs:
     diff-lcs (1.2.5)
-    knapsack (1.6.0)
+    knapsack (4.0.0)
       rake
-      timecop (>= 0.1.0)
     rake (13.0.6)
     rspec (3.4.0)
       rspec-core (~> 3.4.0)
@@ -19,7 +18,6 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.4.0)
     rspec-support (3.4.1)
-    timecop (0.8.0)
 
 PLATFORMS
   ruby