diff --git a/api/build.gradle.kts b/api/build.gradle.kts
index 7533d38..8c5d121 100755
--- a/api/build.gradle.kts
+++ b/api/build.gradle.kts
@@ -151,18 +151,18 @@ dependencies {
 
 
     // Langchain4j
-    implementation("dev.langchain4j:langchain4j-easy-rag:0.36.0")
-    implementation("dev.langchain4j:langchain4j-pgvector:0.36.0")
-    implementation("dev.langchain4j:langchain4j-document-parser-apache-pdfbox:0.36.0")
-    implementation("dev.langchain4j:langchain4j-web-search-engine-google-custom:0.36.0")
-    implementation("dev.langchain4j:langchain4j-hugging-face:0.36.0")
-    implementation("dev.langchain4j:langchain4j-spring-boot-starter:0.36.0")
-    implementation("dev.langchain4j:langchain4j-ollama-spring-boot-starter:0.36.0")
-    implementation("dev.langchain4j:langchain4j-vertex-ai-gemini-spring-boot-starter:0.36.0")
-    testImplementation("dev.langchain4j:langchain4j-spring-boot-tests:0.36.0")
-//    implementation("dev.langchain4j:langchain4j-vertex-ai:0.36.0")
-//    implementation("dev.langchain4j:langchain4j-google-ai-gemini:0.36.0")
-//    implementation("dev.langchain4j:langchain4j-vertex-ai-gemini:0.36.0")
+    implementation("dev.langchain4j:langchain4j-easy-rag:${properties["langchain4j.version"]}")
+    implementation("dev.langchain4j:langchain4j-pgvector:${properties["langchain4j.version"]}")
+    implementation("dev.langchain4j:langchain4j-document-parser-apache-pdfbox:${properties["langchain4j.version"]}")
+    implementation("dev.langchain4j:langchain4j-web-search-engine-google-custom:${properties["langchain4j.version"]}")
+    implementation("dev.langchain4j:langchain4j-hugging-face:${properties["langchain4j.version"]}")
+    implementation("dev.langchain4j:langchain4j-spring-boot-starter:${properties["langchain4j.version"]}")
+    implementation("dev.langchain4j:langchain4j-ollama-spring-boot-starter:${properties["langchain4j.version"]}")
+    implementation("dev.langchain4j:langchain4j-vertex-ai-gemini-spring-boot-starter:${properties["langchain4j.version"]}")
+    testImplementation("dev.langchain4j:langchain4j-spring-boot-tests:${properties["langchain4j.version"]}")
+//    implementation("dev.langchain4j:langchain4j-vertex-ai:${properties["langchain4j.version"]}")
+//    implementation("dev.langchain4j:langchain4j-google-ai-gemini:${properties["langchain4j.version"]}")
+//    implementation("dev.langchain4j:langchain4j-vertex-ai-gemini:${properties["langchain4j.version"]}")
 
 
     // misc
diff --git a/api/gradle.properties b/api/gradle.properties
index fb4b3cc..89408f4 100755
--- a/api/gradle.properties
+++ b/api/gradle.properties
@@ -45,6 +45,7 @@ arrow-kt_jackson.version=0.14.1
 node-gradle.version=7.0.2
 jbake-gradle.version=5.5.0
 kotlinx-serialization-json.version=1.7.2
+langchain4j.version=0.36.0
 #docker_registry=
 #docker_hub_login=
 #docker_hub_email=