diff --git a/frontend/src/solve.cpp b/frontend/src/solve.cpp
index 904eade..60b4cbe 100644
--- a/frontend/src/solve.cpp
+++ b/frontend/src/solve.cpp
@@ -31,7 +31,7 @@ API primitive_generation_result_t generate_polymesh(implicit_network_solver* sol
     result.mesh.num_vertices = static_cast<uint32_t>(output_vertices.size());
     result.mesh.num_faces    = static_cast<uint32_t>(output_vertex_counts_of_face.size());
     vector3d* vertices       = (vector3d*)mi_malloc(sizeof(vector3d) * result.mesh.num_vertices);
-    uint32_t* faces          = (uint32_t*)mi_malloc(sizeof(uint32_t) * result.mesh.num_faces);
+    uint32_t* faces          = (uint32_t*)mi_malloc(sizeof(uint32_t) * output_polygon_faces.size());
     uint32_t* vertex_counts  = (uint32_t*)mi_malloc(sizeof(uint32_t) * result.mesh.num_faces);
     for (uint32_t i = 0; i < result.mesh.num_vertices; i++) {
         std::move(output_vertices[i].data(), output_vertices[i].data() + 3, &vertices[i].x);