diff --git a/src/message.rs b/src/message.rs
index 85b94d9..5165ca6 100644
--- a/src/message.rs
+++ b/src/message.rs
@@ -920,6 +920,7 @@ enum FieldType {
     Uuid,
 }
 
+#[derive(Clone, Debug)]
 enum Field {
     StaticString(String),
     Uuid(Uuid),
@@ -929,19 +930,47 @@ impl Field {
     fn get_type(&self) -> FieldType {
         match self {
             Self::StaticString(_) => FieldType::StaticString,
+            Self::Uuid(_) => FieldType::Uuid,
         }
     }
 }
 
+impl From<String> for Field {
+    fn from(value: String) -> Self {
+        Self::StaticString(value)
+    }
+}
+
+impl From<Uuid> for Field {
+    fn from(value: Uuid) -> Self {
+        Self::Uuid(value)
+    }
+}
+
 #[cfg(test)]
 mod fields {
     use super::*;
 
     #[test]
     fn can_create_static_string() {
+        let data = Uuid::new_v4().to_string();
+        let result: Field = data.clone().into();
+        match result.clone() {
+            Field::StaticString(output) => assert_eq!(output, data),
+            _ => unreachable!("got {:?}: should have been static string", result),
+        }
+        assert_eq!(result.get_type(), FieldType::StaticString);
+    }
+
+    #[test]
+    fn create_uuid() {
         let data = Uuid::new_v4();
-        let sstring = Field::StaticString(data.to_string());
-        assert_eq!(sstring.get_type(), FieldType::StaticString);
+        let result: Field = data.clone().into();
+        match result.clone() {
+            Field::Uuid(output) => assert_eq!(output, data),
+            _ => unreachable!("got {:?}: should have been uuid", result),
+        }
+        assert_eq!(result.get_type(), FieldType::Uuid);
     }
 }
 
@@ -978,11 +1007,53 @@ mod fieldsettings {
 }
 
 #[derive(Clone, Debug)]
-struct Addition;
+struct Addition {
+    data: HashMap<String, Field>,
+}
 
 impl Addition {
     fn new() -> Self {
-        Self {}
+        Self {
+            data: HashMap::new(),
+        }
+    }
+
+    fn add_field<F>(&mut self, name: String, field: F) where F: Into<Field> {
+        self.data.insert(name, field.into());
+    }
+
+    fn get_field(&self, name: &str) -> Option<&Field> {
+        self.data.get(name)
+    }
+}
+
+#[cfg(test)]
+mod additions {
+    use super::*;
+
+    #[test]
+    fn can_add_static_string() {
+        let mut add = Addition::new();
+        let name = Uuid::new_v4().to_string();
+        let data = Uuid::new_v4().to_string();
+        add.add_field(name.clone(), data.clone());
+        let result = add.get_field(&name).unwrap();
+        match result {
+            Field::StaticString(result) => assert_eq!(result, &data),
+            _ => unreachable!("got {:?}: should have received static string", result),
+        }
+    }
+
+    fn can_add_uuid() {
+        let mut add = Addition::new();
+        let name = Uuid::new_v4().to_string();
+        let data = Uuid::new_v4();
+        add.add_field(name.clone(), data.clone());
+        let result = add.get_field(&name).unwrap();
+        match result {
+            Field::Uuid(result) => assert_eq!(result, &data),
+            _ => unreachable!("got {:?}: should have received uuid", result),
+        }
     }
 }