diff --git a/abstract-document/pom.xml b/abstract-document/pom.xml
index 0117794ea367..de6ef506982c 100644
--- a/abstract-document/pom.xml
+++ b/abstract-document/pom.xml
@@ -29,7 +29,7 @@
     <parent>
         <artifactId>java-design-patterns</artifactId>
         <groupId>com.iluwatar</groupId>
-        <version>1.20.0</version>
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     </parent>
     <artifactId>abstract-document</artifactId>
     <dependencies>
diff --git a/abstract-factory/pom.xml b/abstract-factory/pom.xml
index 2b5c346a7e5a..57bbdb5bbb98 100644
--- a/abstract-factory/pom.xml
+++ b/abstract-factory/pom.xml
@@ -29,7 +29,7 @@
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     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
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   <artifactId>abstract-factory</artifactId>
   <dependencies>
diff --git a/acyclic-visitor/pom.xml b/acyclic-visitor/pom.xml
index 1dd4e20a1941..8ce2b1e27586 100644
--- a/acyclic-visitor/pom.xml
+++ b/acyclic-visitor/pom.xml
@@ -30,7 +30,7 @@
 	<parent>
 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.20.0</version>
+		<version>1.21.0-SNAPSHOT</version>
 	</parent>
 	
 	<artifactId>acyclic-visitor</artifactId>
diff --git a/adapter/pom.xml b/adapter/pom.xml
index 7c9cb213c4f8..b417432c2aab 100644
--- a/adapter/pom.xml
+++ b/adapter/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   <artifactId>adapter</artifactId>
   <dependencies>
diff --git a/aggregator-microservices/aggregator-service/pom.xml b/aggregator-microservices/aggregator-service/pom.xml
index 894ee4b0c0ac..626ddcd0ba4f 100644
--- a/aggregator-microservices/aggregator-service/pom.xml
+++ b/aggregator-microservices/aggregator-service/pom.xml
@@ -29,7 +29,7 @@
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         <groupId>com.iluwatar</groupId>
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     <modelVersion>4.0.0</modelVersion>
 
diff --git a/aggregator-microservices/information-microservice/pom.xml b/aggregator-microservices/information-microservice/pom.xml
index 9b21a5778340..bac47c19c73c 100644
--- a/aggregator-microservices/information-microservice/pom.xml
+++ b/aggregator-microservices/information-microservice/pom.xml
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         <groupId>com.iluwatar</groupId>
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diff --git a/aggregator-microservices/inventory-microservice/pom.xml b/aggregator-microservices/inventory-microservice/pom.xml
index 946f63c743b5..bf613916b3ae 100644
--- a/aggregator-microservices/inventory-microservice/pom.xml
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diff --git a/aggregator-microservices/pom.xml b/aggregator-microservices/pom.xml
index 9b8cc1ed6262..20e912395a05 100644
--- a/aggregator-microservices/pom.xml
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diff --git a/ambassador/pom.xml b/ambassador/pom.xml
index f7ff1ca4d83e..6bfbf50084b1 100644
--- a/ambassador/pom.xml
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diff --git a/api-gateway/api-gateway-service/pom.xml b/api-gateway/api-gateway-service/pom.xml
index bf8e7f203999..f947049a757c 100644
--- a/api-gateway/api-gateway-service/pom.xml
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diff --git a/api-gateway/image-microservice/pom.xml b/api-gateway/image-microservice/pom.xml
index e421a1999987..928b23ed699e 100644
--- a/api-gateway/image-microservice/pom.xml
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index 60700571c438..a46a511177a7 100644
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diff --git a/api-gateway/price-microservice/pom.xml b/api-gateway/price-microservice/pom.xml
index 21f69260a7f4..58730846d6f2 100644
--- a/api-gateway/price-microservice/pom.xml
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   <modelVersion>4.0.0</modelVersion>
diff --git a/async-method-invocation/pom.xml b/async-method-invocation/pom.xml
index 2da01240f52e..28e9705f26c7 100644
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diff --git a/balking/pom.xml b/balking/pom.xml
index dbd916dbb112..500a11c82f6b 100644
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diff --git a/bridge/pom.xml b/bridge/pom.xml
index 380995660359..a86c5bf22c4d 100644
--- a/bridge/pom.xml
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diff --git a/builder/pom.xml b/builder/pom.xml
index 05e9dbfbc58f..9130209fffd2 100644
--- a/builder/pom.xml
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diff --git a/business-delegate/pom.xml b/business-delegate/pom.xml
index 3e98e05d955c..70ad2a1137b3 100644
--- a/business-delegate/pom.xml
+++ b/business-delegate/pom.xml
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 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
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 	<artifactId>business-delegate</artifactId>
 	<dependencies>
diff --git a/caching/pom.xml b/caching/pom.xml
index ffa7513abe4d..f86f8b2bab2f 100644
--- a/caching/pom.xml
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   <artifactId>caching</artifactId>
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diff --git a/callback/pom.xml b/callback/pom.xml
index 0e8831f893c1..4506d0316c6a 100644
--- a/callback/pom.xml
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   <artifactId>callback</artifactId>
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diff --git a/chain/pom.xml b/chain/pom.xml
index 798c9a634f4a..7ff678a154ca 100644
--- a/chain/pom.xml
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   <artifactId>chain</artifactId>
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diff --git a/collection-pipeline/pom.xml b/collection-pipeline/pom.xml
index 77ae4997e262..8c4aad2dd392 100644
--- a/collection-pipeline/pom.xml
+++ b/collection-pipeline/pom.xml
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   <artifactId>collection-pipeline</artifactId>
   <dependencies>
diff --git a/command/pom.xml b/command/pom.xml
index e73d62ae9e2c..6807764561ef 100644
--- a/command/pom.xml
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     <artifactId>java-design-patterns</artifactId>
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   <artifactId>command</artifactId>
   <dependencies>
diff --git a/composite/pom.xml b/composite/pom.xml
index d342506cb6a8..60142cf9061c 100644
--- a/composite/pom.xml
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@@ -29,7 +29,7 @@
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     <artifactId>java-design-patterns</artifactId>
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   <artifactId>composite</artifactId>
   <dependencies>
diff --git a/converter/pom.xml b/converter/pom.xml
index b0d6a20c7603..4caf7b203dc9 100644
--- a/converter/pom.xml
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         <groupId>com.iluwatar</groupId>
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     <modelVersion>4.0.0</modelVersion>
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diff --git a/cqrs/pom.xml b/cqrs/pom.xml
index 4307265b6646..6480f25e9b0f 100644
--- a/cqrs/pom.xml
+++ b/cqrs/pom.xml
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 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.20.0</version>
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 	</parent>
 	<artifactId>cqrs</artifactId>
 	<dependencies>
diff --git a/dao/pom.xml b/dao/pom.xml
index 4ae792658c43..20eb79c535b3 100644
--- a/dao/pom.xml
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   <artifactId>dao</artifactId>
 
diff --git a/data-bus/pom.xml b/data-bus/pom.xml
index a62ea2313de7..9106191af529 100644
--- a/data-bus/pom.xml
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diff --git a/data-mapper/pom.xml b/data-mapper/pom.xml
index 38e8a1fb421f..bbcf42ee6b5d 100644
--- a/data-mapper/pom.xml
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@@ -28,7 +28,7 @@
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 		<groupId>com.iluwatar</groupId>
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-		<version>1.20.0</version>
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 	<artifactId>data-mapper</artifactId>
 	<dependencies>
diff --git a/data-transfer-object/pom.xml b/data-transfer-object/pom.xml
index c5ee474568db..3dcb2dc3ce4d 100644
--- a/data-transfer-object/pom.xml
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diff --git a/decorator/pom.xml b/decorator/pom.xml
index 6a73a27ced2c..a9b9c361d11a 100644
--- a/decorator/pom.xml
+++ b/decorator/pom.xml
@@ -29,7 +29,7 @@
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   <artifactId>decorator</artifactId>
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diff --git a/delegation/pom.xml b/delegation/pom.xml
index 1768fd13f097..62bda23185ff 100644
--- a/delegation/pom.xml
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     <modelVersion>4.0.0</modelVersion>
 
diff --git a/dependency-injection/pom.xml b/dependency-injection/pom.xml
index d81a651e2a86..631fc6b7c03f 100644
--- a/dependency-injection/pom.xml
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@@ -29,7 +29,7 @@
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diff --git a/dirty-flag/pom.xml b/dirty-flag/pom.xml
index 530c65dbfdf5..e91d6c9f4c25 100644
--- a/dirty-flag/pom.xml
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   <groupId>com.iluwatar</groupId>
   <artifactId>dirty-flag</artifactId>
-  <version>1.20.0</version>
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   <name>dirty-flag</name>
   <url>http://maven.apache.org</url>
   <properties>
diff --git a/double-checked-locking/pom.xml b/double-checked-locking/pom.xml
index 17bedb916207..999f78d878af 100644
--- a/double-checked-locking/pom.xml
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@@ -27,7 +27,7 @@
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   <artifactId>double-checked-locking</artifactId>
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diff --git a/double-dispatch/pom.xml b/double-dispatch/pom.xml
index 375d2a3ad32c..875c1b430247 100644
--- a/double-dispatch/pom.xml
+++ b/double-dispatch/pom.xml
@@ -29,7 +29,7 @@
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diff --git a/eip-aggregator/pom.xml b/eip-aggregator/pom.xml
index 5e91e75f7fd1..0cc3aa590d62 100644
--- a/eip-aggregator/pom.xml
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@@ -26,7 +26,7 @@
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     <dependencies>
diff --git a/eip-message-channel/pom.xml b/eip-message-channel/pom.xml
index 33c11eba3cff..9b297f72995e 100644
--- a/eip-message-channel/pom.xml
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@@ -30,7 +30,7 @@
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 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.20.0</version>
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 	<artifactId>eip-message-channel</artifactId>
 	<dependencies>
diff --git a/eip-publish-subscribe/pom.xml b/eip-publish-subscribe/pom.xml
index 1a1a826d67f9..c8bc4de28d7a 100644
--- a/eip-publish-subscribe/pom.xml
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@@ -28,7 +28,7 @@
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 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.20.0</version>
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 	<artifactId>eip-publish-subscribe</artifactId>
 	<dependencies>
diff --git a/eip-splitter/pom.xml b/eip-splitter/pom.xml
index d3467185d4eb..7cb722164492 100644
--- a/eip-splitter/pom.xml
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@@ -26,7 +26,7 @@
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     <dependencies>
diff --git a/eip-wire-tap/pom.xml b/eip-wire-tap/pom.xml
index 497340a792dc..c9f569a554d8 100644
--- a/eip-wire-tap/pom.xml
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@@ -26,7 +26,7 @@
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diff --git a/event-aggregator/pom.xml b/event-aggregator/pom.xml
index 41b9bdd09bb4..a6d473841d2e 100644
--- a/event-aggregator/pom.xml
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@@ -28,7 +28,7 @@
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 		<groupId>com.iluwatar</groupId>
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 	<dependencies>
diff --git a/event-asynchronous/pom.xml b/event-asynchronous/pom.xml
index 36617cb8abce..64e69adb629a 100644
--- a/event-asynchronous/pom.xml
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@@ -29,7 +29,7 @@
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diff --git a/event-driven-architecture/pom.xml b/event-driven-architecture/pom.xml
index 99515f876119..03ff66fed956 100644
--- a/event-driven-architecture/pom.xml
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@@ -31,7 +31,7 @@
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         <groupId>com.iluwatar</groupId>
         <artifactId>java-design-patterns</artifactId>
-        <version>1.20.0</version>
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     </parent>
 
     <artifactId>event-driven-architecture</artifactId>
diff --git a/event-queue/pom.xml b/event-queue/pom.xml
index dad2df79aeed..65bb489c2b9b 100644
--- a/event-queue/pom.xml
+++ b/event-queue/pom.xml
@@ -30,7 +30,7 @@
   <parent>
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     <groupId>com.iluwatar</groupId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>event-queue</artifactId>
   <dependencies>
diff --git a/event-sourcing/pom.xml b/event-sourcing/pom.xml
index 07fba6d50938..bae5e997073c 100644
--- a/event-sourcing/pom.xml
+++ b/event-sourcing/pom.xml
@@ -30,7 +30,7 @@
   <parent>
     <artifactId>java-design-patterns</artifactId>
     <groupId>com.iluwatar</groupId>
-    <version>1.20.0</version>
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   <artifactId>event-sourcing</artifactId>
   <dependencies>
diff --git a/execute-around/pom.xml b/execute-around/pom.xml
index 797d3f573d93..8000c4e2f757 100644
--- a/execute-around/pom.xml
+++ b/execute-around/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   <artifactId>execute-around</artifactId>
   <dependencies>
diff --git a/extension-objects/pom.xml b/extension-objects/pom.xml
index 7ef6035d209e..368ee8c36abc 100644
--- a/extension-objects/pom.xml
+++ b/extension-objects/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <artifactId>java-design-patterns</artifactId>
     <groupId>com.iluwatar</groupId>
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   <modelVersion>4.0.0</modelVersion>
 
diff --git a/facade/pom.xml b/facade/pom.xml
index be831c4eb6c6..a658e4376af2 100644
--- a/facade/pom.xml
+++ b/facade/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>facade</artifactId>
   <dependencies>
diff --git a/factory-kit/pom.xml b/factory-kit/pom.xml
index e15d0956f79e..b6cb46b0ecc8 100644
--- a/factory-kit/pom.xml
+++ b/factory-kit/pom.xml
@@ -30,7 +30,7 @@
     <parent>
         <groupId>com.iluwatar</groupId>
         <artifactId>java-design-patterns</artifactId>
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     <artifactId>factory-kit</artifactId>
     <dependencies>
diff --git a/factory-method/pom.xml b/factory-method/pom.xml
index 2980a7991993..9ea706365db2 100644
--- a/factory-method/pom.xml
+++ b/factory-method/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
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   <artifactId>factory-method</artifactId>
   <dependencies>
diff --git a/feature-toggle/pom.xml b/feature-toggle/pom.xml
index 07559b008450..9f9f2678790c 100644
--- a/feature-toggle/pom.xml
+++ b/feature-toggle/pom.xml
@@ -30,7 +30,7 @@
     <parent>
         <artifactId>java-design-patterns</artifactId>
         <groupId>com.iluwatar</groupId>
-        <version>1.20.0</version>
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     <modelVersion>4.0.0</modelVersion>
 
diff --git a/fluentinterface/pom.xml b/fluentinterface/pom.xml
index cf0d07b017d7..c648602e77cc 100644
--- a/fluentinterface/pom.xml
+++ b/fluentinterface/pom.xml
@@ -29,7 +29,7 @@
     <parent>
         <artifactId>java-design-patterns</artifactId>
         <groupId>com.iluwatar</groupId>
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     <modelVersion>4.0.0</modelVersion>
 
diff --git a/flux/pom.xml b/flux/pom.xml
index 06b16e4cda43..f28c8fbb0197 100644
--- a/flux/pom.xml
+++ b/flux/pom.xml
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     <artifactId>java-design-patterns</artifactId>
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   <artifactId>flux</artifactId>
   <dependencies>
diff --git a/flyweight/pom.xml b/flyweight/pom.xml
index 1dd43d51e3f1..223fae694ea4 100644
--- a/flyweight/pom.xml
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@@ -29,7 +29,7 @@
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   <artifactId>flyweight</artifactId>
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diff --git a/front-controller/pom.xml b/front-controller/pom.xml
index 4f8801f0cfaa..af1e22fff073 100644
--- a/front-controller/pom.xml
+++ b/front-controller/pom.xml
@@ -30,7 +30,7 @@
 	<parent>
 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.20.0</version>
+		<version>1.21.0-SNAPSHOT</version>
 	</parent>
 	<artifactId>front-controller</artifactId>
 	<dependencies>
diff --git a/guarded-suspension/pom.xml b/guarded-suspension/pom.xml
index 9b744978e72b..367d582d57d8 100644
--- a/guarded-suspension/pom.xml
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@@ -30,7 +30,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   <packaging>jar</packaging>
   <artifactId>guarded-suspension</artifactId>
diff --git a/half-sync-half-async/pom.xml b/half-sync-half-async/pom.xml
index 0cd0e9f41a32..e79a05037e03 100644
--- a/half-sync-half-async/pom.xml
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@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
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   <artifactId>half-sync-half-async</artifactId>
   <dependencies>
diff --git a/hexagonal/pom.xml b/hexagonal/pom.xml
index 77a1edc302a8..cb127c91d0f1 100644
--- a/hexagonal/pom.xml
+++ b/hexagonal/pom.xml
@@ -30,7 +30,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
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   <artifactId>hexagonal</artifactId>
   <dependencies>
diff --git a/intercepting-filter/pom.xml b/intercepting-filter/pom.xml
index 3d494802d4ae..f38e6b4f2ae0 100644
--- a/intercepting-filter/pom.xml
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   <artifactId>intercepting-filter</artifactId>
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diff --git a/interpreter/pom.xml b/interpreter/pom.xml
index 573aad8967a9..1e958fa3f70f 100644
--- a/interpreter/pom.xml
+++ b/interpreter/pom.xml
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     <artifactId>java-design-patterns</artifactId>
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   <artifactId>interpreter</artifactId>
   <dependencies>
diff --git a/iterator/pom.xml b/iterator/pom.xml
index e9037fae6102..9d1f4e280dbe 100644
--- a/iterator/pom.xml
+++ b/iterator/pom.xml
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   <artifactId>iterator</artifactId>
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diff --git a/layers/pom.xml b/layers/pom.xml
index bc566b5e31c9..b3cdf0ac76ba 100644
--- a/layers/pom.xml
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 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.20.0</version>
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 	<groupId>com.iluwatar.layers</groupId>
 	<artifactId>layers</artifactId>
diff --git a/lazy-loading/pom.xml b/lazy-loading/pom.xml
index 96a0a53d455f..c7f3679ae32d 100644
--- a/lazy-loading/pom.xml
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diff --git a/marker/pom.xml b/marker/pom.xml
index 92d89574ed94..168abaee8b12 100644
--- a/marker/pom.xml
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   <modelVersion>4.0.0</modelVersion>
 
diff --git a/mediator/pom.xml b/mediator/pom.xml
index a97002fd10f6..83cc0f70d93f 100644
--- a/mediator/pom.xml
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diff --git a/memento/pom.xml b/memento/pom.xml
index 620f93607756..8846bcdcc813 100644
--- a/memento/pom.xml
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diff --git a/model-view-controller/pom.xml b/model-view-controller/pom.xml
index 9186820b6118..d2b223dc2615 100644
--- a/model-view-controller/pom.xml
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   <dependencies>
diff --git a/model-view-presenter/pom.xml b/model-view-presenter/pom.xml
index 45e576171e38..a0f7d31b23b5 100644
--- a/model-view-presenter/pom.xml
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   <artifactId>model-view-presenter</artifactId>
   <name>model-view-presenter</name>
diff --git a/module/pom.xml b/module/pom.xml
index 235fef166e19..56e0a8b35715 100644
--- a/module/pom.xml
+++ b/module/pom.xml
@@ -28,7 +28,7 @@
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 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.20.0</version>
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 	</parent>
 	<artifactId>module</artifactId>
 	<dependencies>
diff --git a/monad/pom.xml b/monad/pom.xml
index 0e335f360901..2e2e34870830 100644
--- a/monad/pom.xml
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diff --git a/monostate/pom.xml b/monostate/pom.xml
index e6fcbcec2f7d..920311a8bac7 100644
--- a/monostate/pom.xml
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   <artifactId>monostate</artifactId>
   <dependencies>
diff --git a/multiton/pom.xml b/multiton/pom.xml
index 3ab7ffcb078c..f1abf43a13f0 100644
--- a/multiton/pom.xml
+++ b/multiton/pom.xml
@@ -29,7 +29,7 @@
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   <dependencies>
diff --git a/mute-idiom/pom.xml b/mute-idiom/pom.xml
index 26a2b0275170..b3f8d8aaf9b0 100644
--- a/mute-idiom/pom.xml
+++ b/mute-idiom/pom.xml
@@ -21,7 +21,7 @@
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 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.20.0</version>
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 	</parent>
 	<artifactId>mute-idiom</artifactId>
 	<dependencies>
diff --git a/mutex/pom.xml b/mutex/pom.xml
index 369ed88b7cfa..ed9e6b264dbc 100644
--- a/mutex/pom.xml
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   <artifactId>mutex</artifactId>
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diff --git a/naked-objects/dom/pom.xml b/naked-objects/dom/pom.xml
index 8a7d420d037d..519e2cc0d883 100644
--- a/naked-objects/dom/pom.xml
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@@ -16,7 +16,7 @@
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 		<groupId>com.iluwatar</groupId>
 		<artifactId>naked-objects</artifactId>
-		<version>1.20.0</version>
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 	<artifactId>naked-objects-dom</artifactId>
diff --git a/naked-objects/fixture/pom.xml b/naked-objects/fixture/pom.xml
index 246506ab85d8..cdb77b1b940e 100644
--- a/naked-objects/fixture/pom.xml
+++ b/naked-objects/fixture/pom.xml
@@ -16,7 +16,7 @@
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 		<groupId>com.iluwatar</groupId>
 		<artifactId>naked-objects</artifactId>
-		<version>1.20.0</version>
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 	<artifactId>naked-objects-fixture</artifactId>
diff --git a/naked-objects/integtests/pom.xml b/naked-objects/integtests/pom.xml
index 5e1aa4e006d8..460f2f5060cc 100644
--- a/naked-objects/integtests/pom.xml
+++ b/naked-objects/integtests/pom.xml
@@ -16,7 +16,7 @@
 	<parent>
 		<groupId>com.iluwatar</groupId>
 		<artifactId>naked-objects</artifactId>
-		<version>1.20.0</version>
+		<version>1.21.0-SNAPSHOT</version>
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 	<artifactId>naked-objects-integtests</artifactId>
diff --git a/naked-objects/pom.xml b/naked-objects/pom.xml
index 2f4fd02127fd..2a1832ea7e63 100644
--- a/naked-objects/pom.xml
+++ b/naked-objects/pom.xml
@@ -15,7 +15,7 @@
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 		<artifactId>java-design-patterns</artifactId>
 		<groupId>com.iluwatar</groupId>
-		<version>1.20.0</version>
+		<version>1.21.0-SNAPSHOT</version>
 	</parent>
 
 	<artifactId>naked-objects</artifactId>
@@ -350,17 +350,17 @@
 			<dependency>
 				<groupId>${project.groupId}</groupId>
 				<artifactId>naked-objects-dom</artifactId>
-				<version>1.20.0</version>
+				<version>1.21.0-SNAPSHOT</version>
 			</dependency>
 			<dependency>
 				<groupId>${project.groupId}</groupId>
 				<artifactId>naked-objects-fixture</artifactId>
-				<version>1.20.0</version>
+				<version>1.21.0-SNAPSHOT</version>
 			</dependency>
 			<dependency>
 				<groupId>${project.groupId}</groupId>
 				<artifactId>naked-objects-webapp</artifactId>
-				<version>1.20.0</version>
+				<version>1.21.0-SNAPSHOT</version>
 			</dependency>
 
 		</dependencies>
diff --git a/naked-objects/webapp/pom.xml b/naked-objects/webapp/pom.xml
index 9c00ac1e9b22..54ccc40afae6 100644
--- a/naked-objects/webapp/pom.xml
+++ b/naked-objects/webapp/pom.xml
@@ -16,7 +16,7 @@
 	<parent>
 		<groupId>com.iluwatar</groupId>
 		<artifactId>naked-objects</artifactId>
-		<version>1.20.0</version>
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 	<artifactId>naked-objects-webapp</artifactId>
diff --git a/null-object/pom.xml b/null-object/pom.xml
index e212ded5e033..099fcfce32eb 100644
--- a/null-object/pom.xml
+++ b/null-object/pom.xml
@@ -29,7 +29,7 @@
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   <artifactId>null-object</artifactId>
   <dependencies>
diff --git a/object-mother/pom.xml b/object-mother/pom.xml
index 2c56d1c3dd58..d22633313ef9 100644
--- a/object-mother/pom.xml
+++ b/object-mother/pom.xml
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     <artifactId>object-mother</artifactId>
     <dependencies>
diff --git a/object-pool/pom.xml b/object-pool/pom.xml
index ca04b1175230..6ad7823c46f7 100644
--- a/object-pool/pom.xml
+++ b/object-pool/pom.xml
@@ -29,7 +29,7 @@
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diff --git a/observer/pom.xml b/observer/pom.xml
index 33564578f107..80720f6a2d0a 100644
--- a/observer/pom.xml
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@@ -29,7 +29,7 @@
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diff --git a/page-object/pom.xml b/page-object/pom.xml
index 1693946776c1..62a8214cb4f5 100644
--- a/page-object/pom.xml
+++ b/page-object/pom.xml
@@ -29,7 +29,7 @@
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diff --git a/partial-response/pom.xml b/partial-response/pom.xml
index 1e45014571e4..04b760ca833e 100644
--- a/partial-response/pom.xml
+++ b/partial-response/pom.xml
@@ -29,7 +29,7 @@
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diff --git a/poison-pill/pom.xml b/poison-pill/pom.xml
index 52b75137a595..fa014d6544c7 100644
--- a/poison-pill/pom.xml
+++ b/poison-pill/pom.xml
@@ -29,7 +29,7 @@
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+    <version>1.21.0-SNAPSHOT</version>
   </parent>
   <artifactId>poison-pill</artifactId>
   <dependencies>
diff --git a/pom.xml b/pom.xml
index bdead5e09a56..69af36c57e23 100644
--- a/pom.xml
+++ b/pom.xml
@@ -21,7 +21,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
+    <version>1.21.0-SNAPSHOT</version>
     <packaging>pom</packaging>
     <inceptionYear>2014</inceptionYear>
     <properties>
diff --git a/private-class-data/pom.xml b/private-class-data/pom.xml
index 13e18be4b4db..219709d3119c 100644
--- a/private-class-data/pom.xml
+++ b/private-class-data/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
+    <version>1.21.0-SNAPSHOT</version>
   </parent>
   <artifactId>private-class-data</artifactId>
   <dependencies>
diff --git a/producer-consumer/pom.xml b/producer-consumer/pom.xml
index d57a195f7c71..3d75f41a99ba 100644
--- a/producer-consumer/pom.xml
+++ b/producer-consumer/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>producer-consumer</artifactId>
   <dependencies>
diff --git a/promise/pom.xml b/promise/pom.xml
index 0dfa70528ed4..7b069c74632e 100644
--- a/promise/pom.xml
+++ b/promise/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>promise</artifactId>
   <dependencies>
diff --git a/property/pom.xml b/property/pom.xml
index c0ffeee57af1..2df23c88f95f 100644
--- a/property/pom.xml
+++ b/property/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
+    <version>1.21.0-SNAPSHOT</version>
   </parent>
   <artifactId>property</artifactId>
   <dependencies>
diff --git a/prototype/pom.xml b/prototype/pom.xml
index 4ab88c48ce38..473ba22740a2 100644
--- a/prototype/pom.xml
+++ b/prototype/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>prototype</artifactId>
   <dependencies>
diff --git a/proxy/pom.xml b/proxy/pom.xml
index fced661a317d..d2d1f552eb1c 100644
--- a/proxy/pom.xml
+++ b/proxy/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>proxy</artifactId>
   <dependencies>
diff --git a/queue-load-leveling/pom.xml b/queue-load-leveling/pom.xml
index 7e5215b3975f..15d81ec6dd94 100644
--- a/queue-load-leveling/pom.xml
+++ b/queue-load-leveling/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>queue-load-leveling</artifactId>
   <dependencies>
diff --git a/reactor/pom.xml b/reactor/pom.xml
index 45ee5ab20d90..f50ff1391ea6 100644
--- a/reactor/pom.xml
+++ b/reactor/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
+    <version>1.21.0-SNAPSHOT</version>
   </parent>
   <artifactId>reactor</artifactId>
   <dependencies>
diff --git a/reader-writer-lock/pom.xml b/reader-writer-lock/pom.xml
index f1bf801384f3..de6e57dc4569 100644
--- a/reader-writer-lock/pom.xml
+++ b/reader-writer-lock/pom.xml
@@ -30,7 +30,7 @@
     <parent>
         <groupId>com.iluwatar</groupId>
         <artifactId>java-design-patterns</artifactId>
-        <version>1.20.0</version>
+        <version>1.21.0-SNAPSHOT</version>
     </parent>
     <artifactId>reader-writer-lock</artifactId>
     <dependencies>
diff --git a/repository/pom.xml b/repository/pom.xml
index a74ddb6287c8..6b0ab438eba4 100644
--- a/repository/pom.xml
+++ b/repository/pom.xml
@@ -29,7 +29,7 @@
     <parent>
         <groupId>com.iluwatar</groupId>
         <artifactId>java-design-patterns</artifactId>
-        <version>1.20.0</version>
+        <version>1.21.0-SNAPSHOT</version>
     </parent>
     <artifactId>repository</artifactId>
     <dependencies>
diff --git a/resource-acquisition-is-initialization/pom.xml b/resource-acquisition-is-initialization/pom.xml
index c92bd402ae3d..4c5499f1c43b 100644
--- a/resource-acquisition-is-initialization/pom.xml
+++ b/resource-acquisition-is-initialization/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>resource-acquisition-is-initialization</artifactId>
   <dependencies>
diff --git a/retry/pom.xml b/retry/pom.xml
index 6db6e014e1e2..80a40a45f600 100644
--- a/retry/pom.xml
+++ b/retry/pom.xml
@@ -26,7 +26,7 @@
     <parent>
         <groupId>com.iluwatar</groupId>
         <artifactId>java-design-patterns</artifactId>
-        <version>1.20.0</version>
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     </parent>
     <artifactId>retry</artifactId>
     <packaging>jar</packaging>
diff --git a/semaphore/pom.xml b/semaphore/pom.xml
index 0016ac3d3142..c2c2d19718b4 100644
--- a/semaphore/pom.xml
+++ b/semaphore/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>semaphore</artifactId>
   <dependencies>
diff --git a/servant/pom.xml b/servant/pom.xml
index 9990f68f6d00..11bfeddd4f5a 100644
--- a/servant/pom.xml
+++ b/servant/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>servant</artifactId>
   <dependencies>
diff --git a/serverless/pom.xml b/serverless/pom.xml
index e6df07d5d69c..f3eea887165e 100644
--- a/serverless/pom.xml
+++ b/serverless/pom.xml
@@ -26,7 +26,7 @@
     <parent>
         <groupId>com.iluwatar</groupId>
         <artifactId>java-design-patterns</artifactId>
-        <version>1.20.0</version>
+        <version>1.21.0-SNAPSHOT</version>
     </parent>
 
     <dependencies>
diff --git a/service-layer/pom.xml b/service-layer/pom.xml
index a9df0d349c2a..4e22d20d0c34 100644
--- a/service-layer/pom.xml
+++ b/service-layer/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
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   </parent>
   <artifactId>service-layer</artifactId>
   <dependencies>
diff --git a/service-locator/pom.xml b/service-locator/pom.xml
index c8a35e04eba0..b4033038a394 100644
--- a/service-locator/pom.xml
+++ b/service-locator/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
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   </parent>
   <artifactId>service-locator</artifactId>
   <dependencies>
diff --git a/singleton/pom.xml b/singleton/pom.xml
index 8033e090de80..ac900d0a6d63 100644
--- a/singleton/pom.xml
+++ b/singleton/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>singleton</artifactId>
   <dependencies>
diff --git a/specification/pom.xml b/specification/pom.xml
index 72f499063417..2e250d8ce9a5 100644
--- a/specification/pom.xml
+++ b/specification/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
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   </parent>
   <artifactId>specification</artifactId>
   <dependencies>
diff --git a/state/pom.xml b/state/pom.xml
index ea681b59851a..f0433d9b5fa0 100644
--- a/state/pom.xml
+++ b/state/pom.xml
@@ -29,7 +29,7 @@
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     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>state</artifactId>
   <dependencies>
diff --git a/step-builder/pom.xml b/step-builder/pom.xml
index 153d426ed687..42946351dd91 100644
--- a/step-builder/pom.xml
+++ b/step-builder/pom.xml
@@ -30,7 +30,7 @@
   <parent>
     <artifactId>java-design-patterns</artifactId>
     <groupId>com.iluwatar</groupId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>step-builder</artifactId>
   <dependencies>
diff --git a/strategy/pom.xml b/strategy/pom.xml
index 4e66a4ce75a7..eec6ad9a24ea 100644
--- a/strategy/pom.xml
+++ b/strategy/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
+    <version>1.21.0-SNAPSHOT</version>
   </parent>
   <artifactId>strategy</artifactId>
   <dependencies>
diff --git a/template-method/pom.xml b/template-method/pom.xml
index 1cf72fc07ac1..bd8255a8be45 100644
--- a/template-method/pom.xml
+++ b/template-method/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
+    <version>1.21.0-SNAPSHOT</version>
   </parent>
   <artifactId>template-method</artifactId>
   <dependencies>
diff --git a/thread-pool/pom.xml b/thread-pool/pom.xml
index fef009f475a2..c4b2cdd282bb 100644
--- a/thread-pool/pom.xml
+++ b/thread-pool/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>thread-pool</artifactId>
   <dependencies>
diff --git a/throttling/pom.xml b/throttling/pom.xml
index d5009d6e6d77..3f8fac4b6034 100644
--- a/throttling/pom.xml
+++ b/throttling/pom.xml
@@ -29,7 +29,7 @@
     <parent>
         <artifactId>java-design-patterns</artifactId>
         <groupId>com.iluwatar</groupId>
-        <version>1.20.0</version>
+        <version>1.21.0-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
 
diff --git a/tls/pom.xml b/tls/pom.xml
index ead043264b5c..2303930e2622 100644
--- a/tls/pom.xml
+++ b/tls/pom.xml
@@ -30,7 +30,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
+    <version>1.21.0-SNAPSHOT</version>
   </parent>
   <artifactId>tls</artifactId>
   <dependencies>
diff --git a/tolerant-reader/pom.xml b/tolerant-reader/pom.xml
index a44e4ff857f0..8b4b1bbc53c6 100644
--- a/tolerant-reader/pom.xml
+++ b/tolerant-reader/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
+    <version>1.21.0-SNAPSHOT</version>
   </parent>
   <artifactId>tolerant-reader</artifactId>
   <dependencies>
diff --git a/trampoline/pom.xml b/trampoline/pom.xml
index 48d27a6181d4..c5a181dd9f66 100644
--- a/trampoline/pom.xml
+++ b/trampoline/pom.xml
@@ -30,7 +30,7 @@
     <parent>
         <groupId>com.iluwatar</groupId>
         <artifactId>java-design-patterns</artifactId>
-        <version>1.20.0</version>
+        <version>1.21.0-SNAPSHOT</version>
 
     </parent>
     <artifactId>trampoline</artifactId>
diff --git a/twin/pom.xml b/twin/pom.xml
index cb6c26808f06..0cfc558d7173 100644
--- a/twin/pom.xml
+++ b/twin/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
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   </parent>
   <artifactId>twin</artifactId>
   <dependencies>
diff --git a/unit-of-work/pom.xml b/unit-of-work/pom.xml
index 0d1a1c6ef2a9..b53075f21e8a 100644
--- a/unit-of-work/pom.xml
+++ b/unit-of-work/pom.xml
@@ -29,7 +29,7 @@
     <parent>
         <artifactId>java-design-patterns</artifactId>
         <groupId>com.iluwatar</groupId>
-        <version>1.20.0</version>
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     <modelVersion>4.0.0</modelVersion>
 
diff --git a/value-object/pom.xml b/value-object/pom.xml
index 2cef7d6f23fc..5a942ff3067a 100644
--- a/value-object/pom.xml
+++ b/value-object/pom.xml
@@ -30,7 +30,7 @@
 	<parent>
 		<groupId>com.iluwatar</groupId>
 		<artifactId>java-design-patterns</artifactId>
-		<version>1.20.0</version>
+		<version>1.21.0-SNAPSHOT</version>
 	</parent>
 	<artifactId>value-object</artifactId>
 	<dependencies>
diff --git a/visitor/pom.xml b/visitor/pom.xml
index fd8b2bf2d727..779673a23fa1 100644
--- a/visitor/pom.xml
+++ b/visitor/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>com.iluwatar</groupId>
     <artifactId>java-design-patterns</artifactId>
-    <version>1.20.0</version>
+    <version>1.21.0-SNAPSHOT</version>
   </parent>
   <artifactId>visitor</artifactId>
   <dependencies>