diff --git a/shard.yml b/shard.yml
index 562cb39..277fa41 100644
--- a/shard.yml
+++ b/shard.yml
@@ -1,5 +1,6 @@
 name: kilt
-version: 0.4.0
+version: 0.4.1
+crystal: '< 2.0.0'
 
 authors:
   - Jerome Gravel-Niquet <jeromegn@gmail.com>
diff --git a/src/kilt/version.cr b/src/kilt/version.cr
index 2153f5a..3d60e94 100644
--- a/src/kilt/version.cr
+++ b/src/kilt/version.cr
@@ -1,3 +1,3 @@
 module Kilt
-  VERSION = "0.4.0"
+  VERSION = "0.4.1"
 end