diff --git a/pkg/codegen/model.go b/pkg/codegen/model.go
index ae56bffb..5164a828 100644
--- a/pkg/codegen/model.go
+++ b/pkg/codegen/model.go
@@ -277,7 +277,7 @@ type AliasType struct {
 }
 
 func (p AliasType) Generate(out *Emitter) error {
-	out.Printf("type %s = %s", p.Alias, p.Name)
+	out.Printlnf("type %s = %s", p.Alias, p.Name)
 
 	return nil
 }
diff --git a/pkg/generator/generate.go b/pkg/generator/generate.go
index 0ea248e4..554063a8 100644
--- a/pkg/generator/generate.go
+++ b/pkg/generator/generate.go
@@ -147,6 +147,14 @@ func (g *Generator) AddFile(fileName string, schema *schemas.Schema) error {
 		return err
 	}
 
+	if schema.ID != "" {
+		if _, processed := o.processedSchemas[schema.ID]; processed {
+			return nil
+		}
+
+		o.processedSchemas[schema.ID] = true
+	}
+
 	return newSchemaGenerator(g, schema, fileName, o).generateRootType()
 }
 
@@ -213,6 +221,7 @@ func (g *Generator) beginOutput(
 		declsBySchema:           map[*schemas.Type]*codegen.TypeDecl{},
 		declsByName:             map[string]*codegen.TypeDecl{},
 		unmarshallersByTypeDecl: map[*codegen.TypeDecl]bool{},
+		processedSchemas:        map[string]bool{},
 	}
 	g.outputs[id] = output
 
diff --git a/pkg/generator/output.go b/pkg/generator/output.go
index 9fd42cf6..8fe756cb 100644
--- a/pkg/generator/output.go
+++ b/pkg/generator/output.go
@@ -16,6 +16,7 @@ type output struct {
 	declsByName             map[string]*codegen.TypeDecl
 	declsBySchema           map[*schemas.Type]*codegen.TypeDecl
 	unmarshallersByTypeDecl map[*codegen.TypeDecl]bool
+	processedSchemas        map[string]bool
 	warner                  func(string)
 }
 
diff --git a/pkg/schemas/model.go b/pkg/schemas/model.go
index 2bb7860c..9852589d 100644
--- a/pkg/schemas/model.go
+++ b/pkg/schemas/model.go
@@ -304,6 +304,7 @@ func AnyOf(types []*Type, baseType *Type) (*Type, error) {
 		return nil, err
 	}
 
+	typ.Required = mergeRequiredUnion(types, baseType)
 	typ.subSchemaType = SubSchemaTypeAnyOf
 	typ.subSchemasCount = len(types)
 
@@ -339,6 +340,29 @@ func MergeTypes(types []*Type, baseType *Type) (*Type, error) {
 	return result, nil
 }
 
+func mergeRequiredUnion(types []*Type, baseType *Type) []string {
+	required := make([]string, len(baseType.Required))
+	copy(required, baseType.Required)
+
+	for _, r := range types[0].Required {
+		valid := true
+
+		for _, t := range types {
+			if !slices.Contains(t.Required, r) {
+				valid = false
+
+				break
+			}
+		}
+
+		if valid && !slices.Contains(required, r) {
+			required = append(required, r) //nolint:makezero
+		}
+	}
+
+	return required
+}
+
 func updateAllRefsValues(structValue *reflect.Value, refPath string) error {
 	switch structValue.Kind() { //nolint:exhaustive
 	case reflect.Struct:
diff --git a/tests/data/core/anyOf/anyOf.1.go b/tests/data/core/anyOf/anyOf.1.go
index 5584cf2e..58e05d0e 100644
--- a/tests/data/core/anyOf/anyOf.1.go
+++ b/tests/data/core/anyOf/anyOf.1.go
@@ -18,13 +18,13 @@ type AnyOf1 struct {
 
 type AnyOf1ConfigurationsElem struct {
 	// Bar corresponds to the JSON schema field "bar".
-	Bar float64 `json:"bar" yaml:"bar" mapstructure:"bar"`
+	Bar *float64 `json:"bar,omitempty" yaml:"bar,omitempty" mapstructure:"bar,omitempty"`
 
 	// Baz corresponds to the JSON schema field "baz".
 	Baz *bool `json:"baz,omitempty" yaml:"baz,omitempty" mapstructure:"baz,omitempty"`
 
 	// Foo corresponds to the JSON schema field "foo".
-	Foo string `json:"foo" yaml:"foo" mapstructure:"foo"`
+	Foo *string `json:"foo,omitempty" yaml:"foo,omitempty" mapstructure:"foo,omitempty"`
 }
 
 type AnyOf1ConfigurationsElem_0 struct {
diff --git a/tests/data/core/anyOf/anyOf.2.go b/tests/data/core/anyOf/anyOf.2.go
index 8a68d370..1d21546b 100644
--- a/tests/data/core/anyOf/anyOf.2.go
+++ b/tests/data/core/anyOf/anyOf.2.go
@@ -15,13 +15,13 @@ type AnyOf2 struct {
 
 type AnyOf2ConfigurationsElem struct {
 	// Bar corresponds to the JSON schema field "bar".
-	Bar float64 `json:"bar" yaml:"bar" mapstructure:"bar"`
+	Bar *float64 `json:"bar,omitempty" yaml:"bar,omitempty" mapstructure:"bar,omitempty"`
 
 	// Baz corresponds to the JSON schema field "baz".
 	Baz *bool `json:"baz,omitempty" yaml:"baz,omitempty" mapstructure:"baz,omitempty"`
 
 	// Foo corresponds to the JSON schema field "foo".
-	Foo string `json:"foo" yaml:"foo" mapstructure:"foo"`
+	Foo *string `json:"foo,omitempty" yaml:"foo,omitempty" mapstructure:"foo,omitempty"`
 }
 
 type AnyOf2ConfigurationsElem_1 struct {
diff --git a/tests/data/core/anyOf/anyOf.3.go b/tests/data/core/anyOf/anyOf.3.go
index 0d38f304..e9ac8b7c 100644
--- a/tests/data/core/anyOf/anyOf.3.go
+++ b/tests/data/core/anyOf/anyOf.3.go
@@ -10,13 +10,13 @@ import yaml "gopkg.in/yaml.v3"
 // object with anyOf properties as root
 type AnyOf3 struct {
 	// Bar corresponds to the JSON schema field "bar".
-	Bar float64 `json:"bar" yaml:"bar" mapstructure:"bar"`
+	Bar *float64 `json:"bar,omitempty" yaml:"bar,omitempty" mapstructure:"bar,omitempty"`
 
 	// Configurations corresponds to the JSON schema field "configurations".
 	Configurations []interface{} `json:"configurations,omitempty" yaml:"configurations,omitempty" mapstructure:"configurations,omitempty"`
 
 	// Foo corresponds to the JSON schema field "foo".
-	Foo string `json:"foo" yaml:"foo" mapstructure:"foo"`
+	Foo *string `json:"foo,omitempty" yaml:"foo,omitempty" mapstructure:"foo,omitempty"`
 }
 
 type AnyOf3_0 struct {
diff --git a/tests/data/core/anyOf/anyOf.4.go b/tests/data/core/anyOf/anyOf.4.go
index 5fea31b6..4cad4a15 100644
--- a/tests/data/core/anyOf/anyOf.4.go
+++ b/tests/data/core/anyOf/anyOf.4.go
@@ -13,10 +13,10 @@ type AnyOf4 []AnyOf4Elem
 type AnyOf4Elem struct {
 	// When consuming a CDEvent, you are consuming a parent event. So, when looking at
 	// the 'from' key, this is the parent's parent.
-	From EmbeddedlinkendFrom `json:"from" yaml:"from" mapstructure:"from"`
+	From *EmbeddedlinkendFrom `json:"from,omitempty" yaml:"from,omitempty" mapstructure:"from,omitempty"`
 
 	// LinkKind corresponds to the JSON schema field "linkKind".
-	LinkKind string `json:"linkKind" yaml:"linkKind" mapstructure:"linkKind"`
+	LinkKind *string `json:"linkKind,omitempty" yaml:"linkKind,omitempty" mapstructure:"linkKind,omitempty"`
 
 	// LinkType corresponds to the JSON schema field "linkType".
 	LinkType EmbeddedlinkendLinkType `json:"linkType" yaml:"linkType" mapstructure:"linkType"`
@@ -25,7 +25,7 @@ type AnyOf4Elem struct {
 	Tags EmbeddedlinkendTags `json:"tags,omitempty" yaml:"tags,omitempty" mapstructure:"tags,omitempty"`
 
 	// Target corresponds to the JSON schema field "target".
-	Target EmbeddedlinkrelationTarget `json:"target" yaml:"target" mapstructure:"target"`
+	Target *EmbeddedlinkrelationTarget `json:"target,omitempty" yaml:"target,omitempty" mapstructure:"target,omitempty"`
 }
 
 // UnmarshalYAML implements yaml.Unmarshaler.
@@ -515,7 +515,9 @@ func (j *Embeddedlinkrelation) UnmarshalJSON(value []byte) error {
 }
 
 type AnyOf4Elem_2 = Embeddedlinkrelation
+
 type AnyOf4Elem_1 = Embeddedlinkpath
+
 type AnyOf4Elem_0 = Embeddedlinkend
 
 // UnmarshalYAML implements yaml.Unmarshaler.
diff --git a/tests/data/core/anyOf/anyOf.6.go b/tests/data/core/anyOf/anyOf.6.go
index f79b40ae..43c3a81c 100644
--- a/tests/data/core/anyOf/anyOf.6.go
+++ b/tests/data/core/anyOf/anyOf.6.go
@@ -152,16 +152,27 @@ func (j *Bar2ContentElem) UnmarshalYAML(value *yaml.Node) error {
 }
 
 type Baz2ContentElem_2 = Baz2
+
 type Baz2ContentElem_0 = Foo2
+
 type AnyOf6Qux2Elem_2 = Baz2
+
 type AnyOf6Qux2Elem_1 = Bar2
+
 type AnyOf6Qux2Elem_0 = Foo2
+
 type Foo2ContentElem_0 = Foo2
+
 type Foo2ContentElem_1 = Bar2
+
 type Foo2ContentElem_2 = Baz2
+
 type Baz2ContentElem_1 = Bar2
+
 type Bar2ContentElem_2 = Baz2
+
 type Bar2ContentElem_1 = Bar2
+
 type Bar2ContentElem_0 = Foo2
 
 // UnmarshalJSON implements json.Unmarshaler.
diff --git a/tests/data/core/anyOf/anyOf.7.go b/tests/data/core/anyOf/anyOf.7.go
index 839864a4..21c6ad0e 100644
--- a/tests/data/core/anyOf/anyOf.7.go
+++ b/tests/data/core/anyOf/anyOf.7.go
@@ -88,6 +88,7 @@ func (j *Item) UnmarshalYAML(value *yaml.Node) error {
 }
 
 type AnyOf7BazElem_0 = Item
+
 type Item struct {
 	// Name corresponds to the JSON schema field "name".
 	Name *string `json:"name,omitempty" yaml:"name,omitempty" mapstructure:"name,omitempty"`
@@ -140,6 +141,7 @@ func (j *AnyOf7BazElem) UnmarshalYAML(value *yaml.Node) error {
 }
 
 type AnyOf7BarElem_0 = Item
+
 type AnyOf7Foo struct {
 	// Name corresponds to the JSON schema field "name".
 	Name *string `json:"name,omitempty" yaml:"name,omitempty" mapstructure:"name,omitempty"`
diff --git a/tests/data/core/anyOf/anyOfMultipleRequired.go b/tests/data/core/anyOf/anyOfMultipleRequired.go
index a44531d6..32a1f712 100644
--- a/tests/data/core/anyOf/anyOfMultipleRequired.go
+++ b/tests/data/core/anyOf/anyOfMultipleRequired.go
@@ -93,16 +93,18 @@ func (j *MultipleRequiredMiddle) UnmarshalYAML(value *yaml.Node) error {
 }
 
 type ComposedWithMultipleRequired_0 = MultipleRequiredBase
+
 type ComposedWithMultipleRequired_1 = MultipleRequiredMiddle
+
 type ComposedWithMultipleRequired struct {
 	// BaseField corresponds to the JSON schema field "baseField".
-	BaseField string `json:"baseField" yaml:"baseField" mapstructure:"baseField"`
+	BaseField *string `json:"baseField,omitempty" yaml:"baseField,omitempty" mapstructure:"baseField,omitempty"`
 
 	// DirectField corresponds to the JSON schema field "directField".
 	DirectField bool `json:"directField" yaml:"directField" mapstructure:"directField"`
 
 	// MiddleField corresponds to the JSON schema field "middleField".
-	MiddleField float64 `json:"middleField" yaml:"middleField" mapstructure:"middleField"`
+	MiddleField *float64 `json:"middleField,omitempty" yaml:"middleField,omitempty" mapstructure:"middleField,omitempty"`
 
 	AdditionalProperties interface{} `mapstructure:",remain"`
 }
diff --git a/tests/data/core/anyOf/anyOfWithDirectProperties.go b/tests/data/core/anyOf/anyOfWithDirectProperties.go
index ddcb65e4..d5248703 100644
--- a/tests/data/core/anyOf/anyOfWithDirectProperties.go
+++ b/tests/data/core/anyOf/anyOfWithDirectProperties.go
@@ -52,6 +52,7 @@ func (j *BaseObject) UnmarshalYAML(value *yaml.Node) error {
 }
 
 type ComposedWithAllOfAndProperties_0 = BaseObject
+
 type ComposedWithAllOfAndProperties struct {
 	// BaseField corresponds to the JSON schema field "BaseField".
 	BaseField string `json:"BaseField" yaml:"BaseField" mapstructure:"BaseField"`
diff --git a/tests/unmarshal_json_test.go b/tests/unmarshal_json_test.go
index e569151a..b576fd08 100644
--- a/tests/unmarshal_json_test.go
+++ b/tests/unmarshal_json_test.go
@@ -85,8 +85,8 @@ func TestJsonUmarshalAnyOf(t *testing.T) {
 					t,
 					&testAnyOf.AnyOf1{
 						Configurations: []testAnyOf.AnyOf1ConfigurationsElem{
-							{Foo: "hello"},
-							{Bar: 2.2},
+							{Foo: ptr("hello")},
+							{Bar: ptr(2.2)},
 							{Baz: ptr(true)},
 						},
 						Flags: "hello",
@@ -115,8 +115,8 @@ func TestJsonUmarshalAnyOf(t *testing.T) {
 					t,
 					&testAnyOf.AnyOf1{
 						Configurations: []testAnyOf.AnyOf1ConfigurationsElem{
-							{Foo: "ciao"},
-							{Bar: 200.0},
+							{Foo: ptr("ciao")},
+							{Bar: ptr(200.0)},
 						},
 						Flags: true,
 					},
@@ -145,8 +145,8 @@ func TestJsonUmarshalAnyOf(t *testing.T) {
 					t,
 					&testAnyOf.AnyOf2{
 						Configurations: []testAnyOf.AnyOf2ConfigurationsElem{
-							{Foo: "ciao"},
-							{Bar: 2.0},
+							{Foo: ptr("ciao")},
+							{Bar: ptr(2.0)},
 							{Baz: ptr(false)},
 						},
 					},
@@ -162,7 +162,7 @@ func TestJsonUmarshalAnyOf(t *testing.T) {
 				assert.Equal(
 					t,
 					&testAnyOf.AnyOf3{
-						Foo: "ciao",
+						Foo: ptr("ciao"),
 					},
 					target,
 				)
@@ -176,7 +176,7 @@ func TestJsonUmarshalAnyOf(t *testing.T) {
 				assert.Equal(
 					t,
 					&testAnyOf.AnyOf3{
-						Bar: 2.0,
+						Bar: ptr(2.0),
 					},
 					target,
 				)