ExecuTorch Native

Note

ExecuTorch Native is experimental. The Python API, the .ptn format, and operator coverage may change.

ExecuTorch Native lowers a PyTorch model to a single .ptn file and runs it on one of several engines. In a .pte, delegates lower the graph ahead of time for specific backends. A .ptn keeps the whole graph without backend-specific information, and each engine lowers it when compiling a method.

.pte:  export -> [quantize] -> to_edge -> to_backend -> to_executorch -> .pte (+ .ptd)
.ptn:  export -> [quantize] -> to_native -> .ptn

Export

import torch
from executorch.exir.native import to_native

ep = torch.export.export(model, example_inputs)
to_native(ep).save("model.ptn")

# Several methods in one file.
to_native({"forward": ep_forward, "prefill": ep_prefill}).save("model.ptn")

The partitioner accepts core ATen ops plus linear, matmul, addmm, scaled_dot_product_attention, rms_norm, native::rope, and TorchAO affine quantize/dequantize ops. TorchAO int4 group-wise weights of linear and embedding, and GGUF k-quant weights from executorch.extension.llm.export.gguf, are stored packed with their scheme in tensor metadata. Each method must lower wholly to one delegate; to_native raises otherwise.

A .ptn is an uncompressed zip with fixed entry names:

Entry	Contents
program.ptg	Methods as graphs; FlatBuffer defined by native_graph.fbs.
program.safetensors	Constants. Byte-identical immutable tensors are stored once.
aliases.json	Deduplicated key to owner key; present only when needed.

Runtime

The C++ runtime reads a .ptn into an in-memory graph and hands each method to an engine through the interfaces in Engine.h.

• EngineHost: process-wide device resources.

• EngineContext: state for one loaded program, including mutable buffers.

• EngineExecutable: one compiled method (set_input, execute, get_output).

An engine rejects a method whose semantics it cannot fully honor.

Engine	Notes
Vulkan	Builds on the ET-VK ComputeGraph and shaders.
ggml	CPU, CUDA, HIP, and Metal variants.

The runtime currently builds only with Meta’s internal Buck setup; there is no open-source build yet.

The source is in exir/native/ and backends/native/.