diff --git a/jsonschema-generator/src/main/java/com/github/victools/jsonschema/generator/SchemaGeneratorConfigBuilder.java b/jsonschema-generator/src/main/java/com/github/victools/jsonschema/generator/SchemaGeneratorConfigBuilder.java
index 0bda5cf6..68ad66c8 100644
--- a/jsonschema-generator/src/main/java/com/github/victools/jsonschema/generator/SchemaGeneratorConfigBuilder.java
+++ b/jsonschema-generator/src/main/java/com/github/victools/jsonschema/generator/SchemaGeneratorConfigBuilder.java
@@ -46,8 +46,6 @@ private static ObjectMapper createDefaultObjectMapper() {
         return JsonMapper.builder()
                 // since version 4.32.0; pretty print by default (can be overridden by supplying explicit mapper)
                 .enable(SerializationFeature.INDENT_OUTPUT)
-                // since version 4.21.0
-                .enable(JsonWriteFeature.WRITE_NUMBERS_AS_STRINGS)
                 // since version 4.25.0; as the above doesn't always work
                 .enable(JsonNodeFeature.STRIP_TRAILING_BIGDECIMAL_ZEROES)
                 .build();
diff --git a/jsonschema-maven-plugin/src/test/java/com/github/victools/jsonschema/plugin/maven/TestClass.java b/jsonschema-maven-plugin/src/test/java/com/github/victools/jsonschema/plugin/maven/TestClass.java
index 8e5f53b2..ce1dd65e 100644
--- a/jsonschema-maven-plugin/src/test/java/com/github/victools/jsonschema/plugin/maven/TestClass.java
+++ b/jsonschema-maven-plugin/src/test/java/com/github/victools/jsonschema/plugin/maven/TestClass.java
@@ -17,9 +17,14 @@
 package com.github.victools.jsonschema.plugin.maven;
 
 import com.fasterxml.jackson.annotation.JsonClassDescription;
+import jakarta.validation.constraints.Size;
 
 @JsonClassDescription("Jackson annotation class")
 public class TestClass {
+
+    @Size(min = 1)
+    private String name;
+
     private int anInt;
 
     public TestClass(int anInt) {
@@ -29,4 +34,8 @@ public TestClass(int anInt) {
     public int getAnInt() {
         return this.anInt;
     }
+
+    public String getName() {
+        return this.name;
+    }
 }
diff --git a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Complete-reference.json b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Complete-reference.json
index 1611e491..b0ba96c4 100644
--- a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Complete-reference.json
+++ b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Complete-reference.json
@@ -1 +1 @@
-{"type":"object","properties":{"anInt":{"type":"integer"},"getAnInt()":{"type":"integer"}},"description":"Jackson annotation class","additionalProperties":false}
+{"type":"object","properties":{"anInt":{"type":"integer"},"name":{"type":["string","null"]},"getAnInt()":{"type":"integer"},"getName()":{"type":["string","null"]}},"description":"Jackson annotation class","additionalProperties":false}
diff --git a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/DefaultConfig-reference.json b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/DefaultConfig-reference.json
index d3596b57..651587da 100644
--- a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/DefaultConfig-reference.json
+++ b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/DefaultConfig-reference.json
@@ -4,6 +4,9 @@
   "properties" : {
     "anInt" : {
       "type" : "integer"
+    },
+    "name" : {
+      "type" : "string"
     }
   }
 }
\ No newline at end of file
diff --git a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JacksonSchemaModule-reference.json b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JacksonSchemaModule-reference.json
index fe9e0ca2..d791294a 100644
--- a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JacksonSchemaModule-reference.json
+++ b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JacksonSchemaModule-reference.json
@@ -4,6 +4,9 @@
   "properties" : {
     "anInt" : {
       "type" : "integer"
+    },
+    "name" : {
+      "type" : "string"
     }
   },
   "description" : "Jackson annotation class"
diff --git a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JakartaValidationModule-reference.json b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JakartaValidationModule-reference.json
index d3596b57..3b812f44 100644
--- a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JakartaValidationModule-reference.json
+++ b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JakartaValidationModule-reference.json
@@ -4,6 +4,10 @@
   "properties" : {
     "anInt" : {
       "type" : "integer"
+    },
+    "name" : {
+      "type" : "string",
+      "minLength" : 1
     }
   }
 }
\ No newline at end of file
diff --git a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JavaxValidationModule-reference.json b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JavaxValidationModule-reference.json
index d3596b57..651587da 100644
--- a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JavaxValidationModule-reference.json
+++ b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/JavaxValidationModule-reference.json
@@ -4,6 +4,9 @@
   "properties" : {
     "anInt" : {
       "type" : "integer"
+    },
+    "name" : {
+      "type" : "string"
     }
   }
 }
\ No newline at end of file
diff --git a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/SchemaVersion-reference.json b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/SchemaVersion-reference.json
index f161a82d..9db3fa0c 100644
--- a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/SchemaVersion-reference.json
+++ b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/SchemaVersion-reference.json
@@ -4,6 +4,9 @@
   "properties" : {
     "anInt" : {
       "type" : "integer"
+    },
+    "name" : {
+      "type" : "string"
     }
   }
 }
\ No newline at end of file
diff --git a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Swagger15Module-reference.json b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Swagger15Module-reference.json
index d3596b57..651587da 100644
--- a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Swagger15Module-reference.json
+++ b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Swagger15Module-reference.json
@@ -4,6 +4,9 @@
   "properties" : {
     "anInt" : {
       "type" : "integer"
+    },
+    "name" : {
+      "type" : "string"
     }
   }
 }
\ No newline at end of file
diff --git a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Swagger2Module-reference.json b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Swagger2Module-reference.json
index d3596b57..651587da 100644
--- a/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Swagger2Module-reference.json
+++ b/jsonschema-maven-plugin/src/test/resources/reference-test-cases/Swagger2Module-reference.json
@@ -4,6 +4,9 @@
   "properties" : {
     "anInt" : {
       "type" : "integer"
+    },
+    "name" : {
+      "type" : "string"
     }
   }
 }
\ No newline at end of file