diff --git a/src/types.c b/src/types.c
index 19b1903..826ca86 100644
--- a/src/types.c
+++ b/src/types.c
@@ -90,16 +90,55 @@ GroundValue copyGroundValue(const GroundValue* gv) {
         }
         case FUNCTION: newGv.data.fnVal = gv->data.fnVal; break;
         case STRUCTVAL: {
-            // do this later lmao
-            // FIXME
-            newGv.data.structVal = gv->data.structVal;
+            newGv.data.structVal = malloc(sizeof(GroundStruct));
+            if (newGv.data.structVal == NULL) {
+                printf("Couldn't allocate memory for GroundStruct copy\n");
+                exit(1);
+            }
+            
+            newGv.data.structVal->size = gv->data.structVal->size;
+            newGv.data.structVal->fields = malloc(gv->data.structVal->size * sizeof(GroundStructField));
+            if (newGv.data.structVal->fields == NULL && gv->data.structVal->size > 0) {
+                printf("Couldn't allocate memory for GroundStruct fields copy\n");
+                exit(1);
+            }
+            
+            for (size_t i = 0; i < gv->data.structVal->size; i++) {
+                strncpy(newGv.data.structVal->fields[i].id, 
+                        gv->data.structVal->fields[i].id, 
+                        sizeof(newGv.data.structVal->fields[i].id) - 1);
+                newGv.data.structVal->fields[i].id[sizeof(newGv.data.structVal->fields[i].id) - 1] = '\0';
+                
+                newGv.data.structVal->fields[i].value = copyGroundValue(&gv->data.structVal->fields[i].value);
+            }
             break;
         }
-        case CUSTOM:
-            // also do this later
-            // FIXME
-            newGv.data.customVal = gv->data.customVal;
+        case CUSTOM: {
+            newGv.customType = gv->customType;
+            newGv.data.customVal = malloc(sizeof(GroundObject));
+            if (newGv.data.customVal == NULL) {
+                printf("Couldn't allocate memory for GroundObject copy\n");
+                exit(1);
+            }
+            
+            newGv.data.customVal->fields = NULL;
+            
+            GroundObjectField *field, *tmp;
+            HASH_ITER(hh, gv->data.customVal->fields, field, tmp) {
+                GroundObjectField* newField = malloc(sizeof(GroundObjectField));
+                if (newField == NULL) {
+                    printf("Couldn't allocate memory for GroundObjectField copy\n");
+                    exit(1);
+                }
+                
+                strncpy(newField->id, field->id, sizeof(newField->id) - 1);
+                newField->id[sizeof(newField->id) - 1] = '\0';
+                newField->value = copyGroundValue(&field->value);
+                
+                HASH_ADD_STR(newGv.data.customVal->fields, id, newField);
+            }
             break;
+        }
         case NONE:
         default: {