diff --git a/KotlinServer/Class.kt.twig b/KotlinServer/Class.kt.twig
index 54c0703..5529222 100644
--- a/KotlinServer/Class.kt.twig
+++ b/KotlinServer/Class.kt.twig
@@ -4,9 +4,10 @@
 package {{ packageName }}.api
 
 import com.fasterxml.jackson.annotation.JsonInclude
+import com.fasterxml.jackson.annotation.JsonFormat
 
 import java.math.BigDecimal
-import org.joda.time.DateTime //TODO update
+import java.time.ZonedDateTime
 
 {%- if (description is not empty) %}
 
diff --git a/KotlinServer/blocks/class/constructor-fields-info.twig b/KotlinServer/blocks/class/constructor-fields-info.twig
index 6c14f1f..6789f10 100644
--- a/KotlinServer/blocks/class/constructor-fields-info.twig
+++ b/KotlinServer/blocks/class/constructor-fields-info.twig
@@ -1,5 +1,13 @@
 {%- import '../../utils.twig' as utils -%}
 
 {%- for field in fields %}
-    {{ utils.writeInclusionAnnotation(field.nullable, field.optional) }}{%- if includeVal %}val {% endif %}{{ field.name }}: {{ utils.formatValueType(field.type.type, field.nullable, field.optional) }}{{ utils.writeNullCheckMark(field.nullable, field.optional) }} {%- if (not (loop.last)) or (addCommaAtTheEnd)%}, {% endif %}
+    {%- if field.type.type.baseTypeName == "DateTime" %}
+    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ssX", timezone = "UTC") //TODO use field format
+    {%- endif %}
+    {%- if field.nullable %}
+    @JsonInclude(JsonInclude.Include.ALWAYS)
+    {%- elseif field.optional %}
+    @JsonInclude(JsonInclude.Include.NON_NULL)
+    {%- endif %}
+    {% if includeVal %}val {% endif %}{{ field.name }}: {{ utils.formatValueType(field.type.type, field.nullable, field.optional) }}{{ utils.writeNullCheckMark(field.nullable, field.optional) }} {%- if (not (loop.last)) or (addCommaAtTheEnd)%}, {% endif %}
 {%- endfor -%}
\ No newline at end of file
diff --git a/KotlinServer/utils.twig b/KotlinServer/utils.twig
index 63166b9..e353148 100644
--- a/KotlinServer/utils.twig
+++ b/KotlinServer/utils.twig
@@ -16,10 +16,18 @@
 {%- endif -%}
 {% endmacro %}
 
+{% macro includeDateFormat(valueType) %}
+{%- if valueType.baseTypeName == "DateTime" -%}
+@JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ssX", timezone = "UTC")
+{%- endif -%}
+{% endmacro %}
+
 {% macro formatValueType(valueType, nullable, optional) %}
 {% import _self as self %}
 {%- if valueType.baseTypeName == "Bool" -%}
 Boolean
+{%- elseif valueType.baseTypeName == "DateTime" -%}
+ZonedDateTime
 {%- elseif valueType.baseTypeName == "Decimal" -%}
 BigDecimal
 {%- elseif valueType.baseTypeName == "Map" -%}