Summary
Switch the default hub deployment model from FLUX.1-dev-fp8 to FLUX.2 klein 9B (Q5_K_M GGUF variant from Unsloth).
Motivation
- FLUX.2 klein 9B is a faster, higher-quality compact model released by Black Forest Labs (January 2026)
- The Unsloth Q5_K_M GGUF variant (~7GB) offers near-original quality at a fraction of the size
- Fits easily on ADA_24 (24GB) GPUs already configured for the hub (~16GB VRAM total)
Breaking Change (6.0.0)
This is a breaking change because:
- The default hub image will ship a different model
- Existing workflows using
CheckpointLoaderSimple with flux1-dev-fp8.safetensors won't work on the new default image
- Users can still use the
flux1-dev-fp8 image tag for backward compatibility
Files to Change
Dockerfile - Install ComfyUI-GGUF custom node, add download block, change default MODEL_TYPEdocker-bake.hcl - Add flux2-klein-9b target.github/workflows/release.yml - Add to CI matrix.github/workflows/manual-build-all.yml - Add build job.runpod/hub.json - Update description + disk size.runpod/README.md - Update model references + example workflowREADME.md - Add to available images listdocs/deployment.md - Add GPU recommendation rowtest_input.json - New default workflow.runpod/tests_.json - New test workflowtest_resources/workflows/workflow_flux2_klein_9b_gguf.json - New workflow filesrc/extra_model_paths.yaml - Add diffusion_models + text_encoders paths.changeset/flux2-klein-default.md - Major changeset
Model Details
| File |
Size |
Directory |
flux-2-klein-9b-Q5_K_M.gguf |
7.02 GB |
models/unet/ |
qwen_3_8b_fp8mixed.safetensors |
8.66 GB |
models/text_encoders/ |
flux2-vae.safetensors |
336 MB |
models/vae/ |
Total VRAM: ~16 GB on 24 GB ADA GPUs (8 GB headroom)
Summary
Switch the default hub deployment model from FLUX.1-dev-fp8 to FLUX.2 klein 9B (Q5_K_M GGUF variant from Unsloth).
Motivation
Breaking Change (6.0.0)
This is a breaking change because:
CheckpointLoaderSimplewithflux1-dev-fp8.safetensorswon't work on the new default imageflux1-dev-fp8image tag for backward compatibilityFiles to Change
Dockerfile- Install ComfyUI-GGUF custom node, add download block, change default MODEL_TYPEdocker-bake.hcl- Add flux2-klein-9b target.github/workflows/release.yml- Add to CI matrix.github/workflows/manual-build-all.yml- Add build job.runpod/hub.json- Update description + disk size.runpod/README.md- Update model references + example workflowREADME.md- Add to available images listdocs/deployment.md- Add GPU recommendation rowtest_input.json- New default workflow.runpod/tests_.json- New test workflowtest_resources/workflows/workflow_flux2_klein_9b_gguf.json- New workflow filesrc/extra_model_paths.yaml- Add diffusion_models + text_encoders paths.changeset/flux2-klein-default.md- Major changesetModel Details
flux-2-klein-9b-Q5_K_M.ggufmodels/unet/qwen_3_8b_fp8mixed.safetensorsmodels/text_encoders/flux2-vae.safetensorsmodels/vae/Total VRAM: ~16 GB on 24 GB ADA GPUs (8 GB headroom)