diff --git a/src/device.rs b/src/device.rs
index 9af5d2c..b63c333 100644
--- a/src/device.rs
+++ b/src/device.rs
@@ -155,7 +155,7 @@ impl Device {
             None => Vec::new(),
         };
 
-        let outputs = Self::flatten(
+        let outputs = flatten(
             self.supported_events
                 .iter()
                 .map(|(event_type, kinds)| {
@@ -219,8 +219,8 @@ impl Device {
         }
     }
 
-    fn flatten<T>(vv: Vec<Vec<T>>) -> Vec<T> {
-        vv.into_iter().flatten().collect()
+    pub fn events(&self) -> &HashMap<EventType, Vec<EventCode>> {
+        &self.supported_events
     }
 }
 
diff --git a/src/event_code_iters.rs b/src/event_code_iters.rs
index 9e1e563..c67cbd2 100644
--- a/src/event_code_iters.rs
+++ b/src/event_code_iters.rs
@@ -679,3 +679,7 @@ pub fn code_to_string(code: &EventCode) -> String {
         _ => panic!(),
     }
 }
+
+pub fn flatten<T>(vv: Vec<Vec<T>>) -> Vec<T> {
+    vv.into_iter().flatten().collect()
+}
diff --git a/src/graph_editor_egui.rs b/src/graph_editor_egui.rs
index fd198a4..06aec84 100644
--- a/src/graph_editor_egui.rs
+++ b/src/graph_editor_egui.rs
@@ -56,7 +56,7 @@ pub fn draw_graph_editor(
         }
         node_finder_area.show(ctx, |ui| {
             // don't allow a nodes to be duplicated
-            let devs: Vec<&Device> = devices
+            let missing_devices: Vec<&Device> = devices
                 .iter()
                 .filter(|device| {
                     let mut allow = true;
@@ -72,7 +72,29 @@ pub fn draw_graph_editor(
                 })
                 .collect();
 
-            if let Some(node_device) = node_finder.show(&devs, virtual_device.is_none(), ui) {
+            if let Some(mut node_device) =
+                node_finder.show(&missing_devices, virtual_device.is_none(), ui)
+            {
+                if let SelectedDevice::Virtual(virt) = &mut node_device {
+                    let existing_devices: Vec<&Device> = devices
+                        .iter()
+                        .filter(|device| {
+                            let mut exists = false;
+
+                            for (_node_id, node) in state.graph.nodes.iter() {
+                                if node.op_name == device.name() {
+                                    exists = true;
+                                    break;
+                                }
+                            }
+
+                            exists
+                        })
+                        .collect();
+
+                    virt.build_ports(&existing_devices);
+                }
+
                 let new_node = state.graph.add_node(node_device.to_descriptor());
                 state
                     .node_positions
diff --git a/src/node_finder.rs b/src/node_finder.rs
index fa037c2..e38da52 100644
--- a/src/node_finder.rs
+++ b/src/node_finder.rs
@@ -58,6 +58,7 @@ impl NodeFinder {
         // The archetype that will be returned.
         let mut submitted_device = None;
         frame.show(ui, |ui| {
+            ui.set_width(250.0);
             ui.vertical(|ui| {
                 Frame::default().margin(vec2(10.0, 10.0)).show(ui, |ui| {
                     if allow_virt_dev {
diff --git a/src/virtual_device.rs b/src/virtual_device.rs
index 9227496..ae23d21 100644
--- a/src/virtual_device.rs
+++ b/src/virtual_device.rs
@@ -1,8 +1,20 @@
-use crate::{graph_types::NodeDescriptor, id_types::NodeId};
+use std::collections::{HashMap, HashSet};
+
+use evdev_rs::enums::{EventCode, EventType};
+
+use crate::{
+    device::Device,
+    event_code_iters::{code_to_string, flatten},
+    graph_types::{Descriptor, NodeDescriptor},
+    id_types::NodeId,
+};
 
 pub struct VirtualDevice {
     name: String,
     node_id: Option<NodeId>,
+
+    inputs: HashMap<EventType, Vec<EventCode>>,
+    outputs: HashMap<EventType, Vec<EventCode>>,
 }
 
 impl VirtualDevice {
@@ -10,6 +22,9 @@ impl VirtualDevice {
         Self {
             name: name.to_string(),
             node_id: None,
+
+            inputs: HashMap::new(),
+            outputs: HashMap::new(),
         }
     }
 
@@ -17,6 +32,62 @@ impl VirtualDevice {
         self.node_id = Some(node_id);
     }
 
+    pub fn build_ports(&mut self, devices: &[&Device]) {
+        let mut inputs: HashMap<EventType, HashSet<EventCode>> = HashMap::new();
+        let mut outputs: HashMap<EventType, HashSet<EventCode>> = HashMap::new();
+
+        for device in devices {
+            for (event_type, new_codes) in device.events() {
+                match event_type {
+                    EventType::EV_KEY | EventType::EV_REL | EventType::EV_ABS => {
+                        match inputs.get_mut(event_type) {
+                            Some(codes) => {
+                                for code in new_codes {
+                                    codes.insert(*code);
+                                }
+                            }
+                            None => {
+                                let mut codes = HashSet::new();
+
+                                for code in new_codes {
+                                    codes.insert(*code);
+                                }
+
+                                inputs.insert(*event_type, codes);
+                            }
+                        }
+                    }
+                    EventType::EV_FF => match outputs.get_mut(event_type) {
+                        Some(codes) => {
+                            for code in new_codes {
+                                codes.insert(*code);
+                            }
+                        }
+                        None => {
+                            let mut codes = HashSet::new();
+
+                            for code in new_codes {
+                                codes.insert(*code);
+                            }
+
+                            outputs.insert(*event_type, codes);
+                        }
+                    },
+
+                    _ => (),
+                }
+            }
+        }
+
+        for (event_type, codes) in inputs {
+            self.inputs.insert(event_type, codes.into_iter().collect());
+        }
+
+        for (event_type, codes) in outputs {
+            self.outputs.insert(event_type, codes.into_iter().collect());
+        }
+    }
+
     pub fn node_id(&self) -> NodeId {
         self.node_id.unwrap()
     }
@@ -24,8 +95,28 @@ impl VirtualDevice {
     pub fn to_descriptor(&self) -> NodeDescriptor {
         NodeDescriptor {
             op_name: self.name.clone(),
-            inputs: Vec::new(),
-            outputs: Vec::new(),
+            inputs: flatten(
+                self.inputs
+                    .iter()
+                    .map(|(_event_type, codes)| {
+                        codes
+                            .iter()
+                            .map(|code| (code_to_string(code), Descriptor::Button))
+                            .collect::<Vec<(String, Descriptor)>>()
+                    })
+                    .collect::<Vec<Vec<(String, Descriptor)>>>(),
+            ),
+            outputs: flatten(
+                self.outputs
+                    .iter()
+                    .map(|(_event_type, codes)| {
+                        codes
+                            .iter()
+                            .map(|code| (code_to_string(code), Descriptor::Button))
+                            .collect::<Vec<(String, Descriptor)>>()
+                    })
+                    .collect::<Vec<Vec<(String, Descriptor)>>>(),
+            ),
         }
     }
 }