diff --git a/shard.yml b/shard.yml
index 6c4bb317..ee21a415 100644
--- a/shard.yml
+++ b/shard.yml
@@ -15,6 +15,6 @@ scripts:
 executables:
   - ameba
 
-crystal: "~> 1.5.0"
+crystal: "~> 1.6.0"
 
 license: MIT