diff --git a/samples/demo-server/src/customs.rs b/samples/demo-server/src/customs.rs
new file mode 100644
index 00000000..2d78fb12
--- /dev/null
+++ b/samples/demo-server/src/customs.rs
@@ -0,0 +1,189 @@
+use std::sync::Arc;
+
+use opcua::{
+    nodes::{DataTypeBuilder, ObjectBuilder, ReferenceDirection},
+    server::node_manager::memory::SimpleNodeManager,
+    types::{
+        DataTypeDefinition, DataTypeId, EnumDefinition, EnumField, NodeId, ReferenceTypeId,
+        StructureDefinition, StructureField, StructureType,
+    },
+};
+
+pub fn add_custom_types(nm: Arc<SimpleNodeManager>, ns: u16) {
+    let enum_id = add_enum_data_type(&nm, ns);
+    add_custom_data_type(&nm, ns, &enum_id);
+}
+
+fn enum_field(name: &str, value: i64) -> EnumField {
+    EnumField {
+        name: name.into(),
+        description: name.into(),
+        display_name: name.into(),
+        value,
+    }
+}
+
+fn add_enum_data_type(nm: &Arc<SimpleNodeManager>, ns: u16) -> NodeId {
+    let mut addr = nm.address_space().write();
+
+    let id = NodeId::next_numeric(ns);
+
+    let type_def = DataTypeDefinition::Enum(EnumDefinition {
+        fields: Some(vec![
+            enum_field("Disabled", 1),
+            enum_field("Enabled", 2),
+            enum_field("Idle", 3),
+            enum_field("MoveAbs", 4),
+            enum_field("Error", 5),
+        ]),
+    });
+    DataTypeBuilder::new(&id, "AxisState", "AxisState")
+        .organized_by(&DataTypeId::Enumeration)
+        .data_type_definition(type_def)
+        .insert(&mut *addr);
+
+    id
+}
+
+fn add_encoding(nm: &SimpleNodeManager, ns: u16, struct_id: &NodeId) -> NodeId {
+    let mut addr = nm.address_space().write();
+    let id = NodeId::next_numeric(ns);
+    ObjectBuilder::new(&id, "DefaultBinary", "DefaultBindary")
+        .reference(
+            struct_id,
+            ReferenceTypeId::HasEncoding,
+            ReferenceDirection::Inverse,
+        )
+        .insert(&mut *addr);
+    id
+}
+
+fn add_custom_data_type(nm: &SimpleNodeManager, ns: u16, e_state_id: &NodeId) -> NodeId {
+    let struct_id = NodeId::next_numeric(ns);
+    let enc_id = add_encoding(nm, ns, &struct_id);
+
+    let type_def = DataTypeDefinition::Structure(StructureDefinition {
+        default_encoding_id: NodeId::null(),
+        base_data_type: DataTypeId::Structure.into(),
+        structure_type: StructureType::Structure,
+        fields: Some(vec![
+            StructureField {
+                name: "sErrorMessage".into(),
+                data_type: DataTypeId::String.into(),
+                value_rank: -1,
+                ..Default::default()
+            },
+            StructureField {
+                name: "nErrorID".into(),
+                data_type: DataTypeId::UInt32.into(),
+                value_rank: -1,
+                ..Default::default()
+            },
+            StructureField {
+                name: "eLastState".into(),
+                data_type: e_state_id.clone(),
+                value_rank: -1,
+                ..Default::default()
+            },
+        ]),
+    });
+    let mut addr = nm.address_space().write();
+    DataTypeBuilder::new(&struct_id, "ErrorData", "ErrorData")
+        .organized_by(&DataTypeId::Structure)
+        .data_type_definition(type_def)
+        .reference(
+            enc_id,
+            ReferenceTypeId::HasEncoding,
+            ReferenceDirection::Forward,
+        )
+        .insert(&mut *addr);
+
+    struct_id
+}
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+#[repr(i32)]
+pub enum AxisState {
+    Disabled = 1i32,
+    Enabled = 2i32,
+    Idle = 3i32,
+    MoveAbs = 4i32,
+    Error = 5i32,
+}
+
+impl Default for AxisState {
+    fn default() -> Self {
+        Self::Disabled
+    }
+}
+
+impl TryFrom<i32> for AxisState {
+    type Error = opcua::types::Error;
+    fn try_from(value: i32) -> Result<Self, <Self as TryFrom<i32>>::Error> {
+        Ok(match value {
+            1i32 => Self::Disabled,
+            2i32 => Self::Enabled,
+            3i32 => Self::Idle,
+            4i32 => Self::MoveAbs,
+            5i32 => Self::Error,
+            r => {
+                return Err(opcua::types::Error::decoding(format!(
+                    "Got unexpected value for enum AxisState: {}",
+                    r
+                )));
+            }
+        })
+    }
+}
+
+impl From<AxisState> for i32 {
+    fn from(value: AxisState) -> Self {
+        value as i32
+    }
+}
+impl opcua::types::IntoVariant for AxisState {
+    fn into_variant(self) -> opcua::types::Variant {
+        (self as i32).into_variant()
+    }
+}
+
+impl opcua::types::BinaryEncodable for AxisState {
+    fn byte_len(&self, _ctx: &opcua::types::Context<'_>) -> usize {
+        4usize
+    }
+    fn encode<S: std::io::Write + ?Sized>(
+        &self,
+        stream: &mut S,
+        _ctx: &opcua::types::Context<'_>,
+    ) -> opcua::types::EncodingResult<()> {
+        opcua::types::write_i32(stream, *self as i32)
+    }
+}
+impl opcua::types::BinaryDecodable for AxisState {
+    fn decode<S: std::io::Read + ?Sized>(
+        stream: &mut S,
+        _ctx: &opcua::types::Context<'_>,
+    ) -> opcua::types::EncodingResult<Self> {
+        let value = opcua::types::read_i32(stream)?;
+        Self::try_from(value)
+    }
+}
+
+#[derive(
+    Debug, Clone, PartialEq, Default, opcua::types::BinaryEncodable, opcua::types::BinaryDecodable,
+)]
+pub struct ErrorData {
+    message: opcua::types::UAString,
+    error_id: u32,
+    last_state: AxisState,
+}
+
+impl ErrorData {
+    pub fn new(msg: &str, error_id: u32, last_state: AxisState) -> Self {
+        Self {
+            message: msg.into(),
+            error_id: error_id,
+            last_state: last_state,
+        }
+    }
+}
diff --git a/samples/demo-server/src/main.rs b/samples/demo-server/src/main.rs
index 3c00ad7e..b7f4cd1e 100644
--- a/samples/demo-server/src/main.rs
+++ b/samples/demo-server/src/main.rs
@@ -26,6 +26,7 @@ use opcua::server::{
 };
 
 mod control;
+mod customs;
 mod machine;
 mod methods;
 mod scalar;
@@ -134,6 +135,9 @@ async fn main() {
 
         let token = handle.token();
 
+        // Define some custom types
+        customs::add_custom_types(node_manager.clone(), ns);
+
         // Add some objects representing machinery
         machine::add_machinery(
             ns,