---
title: Klein LoRA Studio
emoji: 🎨
colorFrom: green
colorTo: gray
sdk: gradio
sdk_version: 5.49.1
app_file: app.py
pinned: false
license: apache-2.0
suggested_hardware: zero-a10g
short_description: Restyle photos with your own trained klein 4B signature look
models:
  - black-forest-labs/FLUX.2-klein-4B
  - black-forest-labs/FLUX.2-klein-base-4B
tags:
  - build-small-hackathon
  - backyard-ai
  - tiny-titan
  - off-brand
  - best-demo
  - flux
  - image-to-image
  - lora
---

# 🎨 Klein LoRA Studio

**Restyle a photo into a named look — and make that look *yours*.** Drop in a
photo, pick a look (Scandinavian, Cottagecore, Watercolor…), and see a clean
**before → after**. Load a `.safetensors` LoRA you trained and the look becomes a
**consistent signature** — the thing a plain prompt can't give you. Built for the
[Build Small Hackathon](https://huggingface.co/build-small-hackathon) (🏡 *Backyard
AI* track) on **FLUX.2 [klein] 4B**.

> ▶️ **Demo video:** _add link_  ·  📣 **Social post:** _add link_

## How it works

1. **Upload** a photo (a room, an outfit, a garden…).
2. **Pick a look** — each is a curated edit prompt. See **Before | After** side
   by side.
3. **Optional: load your signature LoRA** (`.safetensors`) + a strength slider, so
   every restyle carries *your* aesthetic — consistent across a whole set.

## Idea & tech (Build Small write-up)

- **The insight.** Named presets hide the prompt engineering; a **LoRA** makes the
  look consistent and recognizable — not promptable by anyone. Before/after demos
  far better than a single image.
- **The model.** [`FLUX.2-klein-4B`](https://huggingface.co/black-forest-labs/FLUX.2-klein-4B)
  — 4B params, **Apache 2.0**, runs on the Space GPU (~13 GB, 4-step distilled).
- **The engine.** A `diffusers` `Flux2KleinPipeline` in **image→image** mode
  (ZeroGPU pattern: build on CPU at module scope, move to GPU in `@spaces.GPU`).
  A `.safetensors` LoRA is attached with `load_lora_weights(...)` /
  `set_adapters(...)` and always unloaded in a `finally` so the shared pipe stays
  clean. `peft` is the diffusers LoRA backend.
- **The craft.** Curated look presets + an optional signature LoRA + a before/after
  layout, in a custom single-purpose UI (not the stock starter tabs).
- **Renders reliably on Spaces.** System-font theme (no Google-Fonts fetch) and
  `ssr_mode=False`.

## Get a signature LoRA (≈ $0.50, ≈ 30 min)

No LoRA needed to try the looks — but training one is the whole point. See
`TRAIN_A_LORA.md` and `configs/my_lora_klein_4b.yaml`: 15–40 images of one
aesthetic, caption *content only* with a coined trigger, train on
`FLUX.2-klein-base-4B` via AI Toolkit, then upload the `.safetensors` here.

## Why it fits "Build Small"

| Rule / badge | How Klein LoRA Studio delivers it |
| --- | --- |
| **REQ-01 · Models ≤ 32B** | klein **4B** (+ tiny LoRA) — also ≤ 4B → 🏅 **Tiny Titan**. |
| **REQ-02 · Gradio app in the org** | A Gradio Space; deploy/duplicate into the Build Small HF org. |
| **REQ-03 · Demo video** | _add link above_ |
| **REQ-04 · Social post** | _add link above_ |
| **REQ-05 · ZeroGPU limit** | Single ZeroGPU Space (`zero-a10g`). |
| **REQ-06 · Tagged README** | Track + badge tags + this write-up. |
| 🎨 **Off Brand** | Custom before/after studio UI. |
| 🎬 **Best Demo** | Side-by-side restyle + a signature LoRA tells a story. |

## Submission checklist

- [x] Runs on klein 4B (≤ 32B, and ≤ 4B for Tiny Titan)
- [x] Gradio Space
- [ ] Demo video recorded + linked above
- [ ] One social post + linked above
- [ ] Space uploaded into the Build Small org
- [x] README tagged with track + badges + write-up

---

**Links:** [FLUX.2 [klein]](https://huggingface.co/black-forest-labs/FLUX.2-klein-4B)
· [GitHub](https://github.com/black-forest-labs/flux2)
· [Docs](https://docs.bfl.ai)
· [Build Small Hackathon](https://huggingface.co/build-small-hackathon)

Built on the [klein Build Small starter](https://huggingface.co/spaces/stephenbtl/klein-build-small-starter).