---
type: reference
description: "Why Lemonade Server can do image generation on Strix Halo when ComfyUI cannot."
tags:
  - research
timestamp: 2026-08-28
---

# Lemonade and sd.cpp

Why Lemonade Server can do image generation on Strix Halo when ComfyUI cannot. Research from the Lemonade source repo (`lemonade-sdk/lemonade`, cloned 2026-08-14) and live verification.

## The short answer

Lemonade does not run ComfyUI. Its image-generation backend is a wrapped **stable-diffusion.cpp** (`leejet/stable-diffusion.cpp`) subprocess. sd.cpp is a ggml-family native C++ runtime that ships its own HIP kernels — and those kernels **include gfx1151**. ComfyUI runs on PyTorch, whose standard wheels omit gfx1151. Same hardware, different runtime, different result.

## From the Lemonade source

`src/cpp/server/backends/sdcpp/sdcpp_server.cpp`:

- Image gen is `SDServer`, a `WrappedServer` around a prebuilt sd.cpp binary.
- Downloads `sd-<version>-bin-Linux-Ubuntu-24.04-x86_64-<backend>.zip` from `leejet/stable-diffusion.cpp` releases.
- Backends: `cpu, cuda, metal, rocm, vulkan`.
- ROCm asset is `...-rocm-<version>.zip`; Vulkan is `...-vulkan.zip`.

Backend support matrix (`serverAppConfigs-docs/dev/backends-reference.md`):

| Recipe | Backend | Device families |
|--------|---------|-----------------|
| `sd-cpp` | rocm | amd_gpu (gfx103X, gfx110X, **gfx1150, gfx1151, gfx1152**, gfx120X) |
| `sd-cpp` | vulkan | amd_gpu; cpu; nvidia_gpu |
| `thenoise` | rocm | amd_gpu (gfx1150, gfx1151, gfx1152) — experimental |

**gfx1151 is explicitly supported** by sd.cpp's ROCm build. There is also a dedicated experimental `thenoise` ROCm backend targeting exactly the Strix Halo archs.

## Engine comparison

| | ComfyUI | Lemonade (sd.cpp) |
|---|---|---|
| Runtime | PyTorch | native C++ (ggml family) |
| AMD path | needs PyTorch ROCm wheel with gfx1151 kernels — not in standard wheels | ships own HIP kernels, gfx1151 included |
| On Strix Halo | CPU only (today) | ROCm GPU, or Vulkan fallback |
| Interface | node graph web UI | server, OpenAI-style API, GUI/CLI |

This mirrors llama.cpp on the same box: ggml-family runtimes ship their own gfx1151 HIP kernels and run on ROCm; PyTorch does not.

## Relevance

- If GPU image generation on Dankclaw matters, **Lemonade (or bare sd.cpp) is the working path today**.
- ComfyUI's node graph is the cost of switching: Lemonade is not ComfyUI.
- See [[ComfyUI ROCm and Vulkan]] for the PyTorch-side analysis showing a gfx1151-enabled torch would also make ComfyUI work.

## See Also

- [[ComfyUI ROCm and Vulkan]] — the PyTorch side of this question
- [[ComfyUI]] — current CPU config
- [[Dankclaw Stack]]