Axolotl v0.18: Production-Scale MoE Fine-Tuning
Fine-Tuning Frontier MoE Models Cheaply
Axolotl v0.18 (released July 2026) is built around one theme: making 4-bit expert LoRA on very large sparse Mixture-of-Experts models fast and memory-flat at long context, on both Blackwell and Hopper GPUs.
NVFP4 MoE-LoRA: Two Kernel Backends
| Backend | Approach | Verified On |
|---|---|---|
| ScatterMoE | Fused NVFP4 (Marlin/DeepGEMM) and bnb-4bit expert paths | Gemma 4 (128 experts), DeepSeek-V3 |
| SonicMoE | Native FP4-activation MoE-LoRA (W4A4) via quack/CUTLASS kernels - beats Marlin W4A16 at every sequence length on B200 | Qwen3-30B-A3B, Qwen3-Next-80B-A3B |
Active VRAM stays nearly flat from 4K to 32K context with both backends, and SonicMoE now also runs on consumer Blackwell (RTX 50-series) via a quack 0.6 migration.
New Model Support
- GLM-5.2 (
glm_moe_dsa): fine-tune from its NVFP4 checkpoint on multi-GPU FSDP2 - 256 routed experts with Lightning-Indexer token selection, following the DeepSeek-V3.2 sparse-MLA lineage, with DeepEP expert parallelism composed in 2D (EP x cp) - Gemma 4 Unified: encoder-free multimodal text + vision LoRA configs with a dedicated chat template
- DeepSeek-V3: MoE-LoRA kernels alongside Gemma 4
- MiniMax M2 (MoE): QLoRA fine-tuning with kernel-optimization patches
- PaddleOCR-VL: multimodal image-text support
Long-Context Training Without OOMs
A new activation_offloading: hidden_states mode offloads only the per-layer checkpoint input to CPU and recomputes the rest - on Qwen3-8B full-parameter training it reaches 128K context where plain gradient checkpointing runs out of memory, with bit-exact gradients.
Multi-Turn Inference Chat Interface
axolotl inference config.yaml --chat
This starts a streaming, multi-turn chat session with runtime-adjustable generation parameters and streaming reasoning blocks for thinking models - useful for sanity-checking a fine-tune without writing a separate eval script.
Dependency Bumps
| Package | Change |
|---|---|
| transformers | 5.9.0 → 5.14.1 |
| trl | 1.5.1 → 1.8.0 |
| liger-kernel | 0.7.0 → 0.8.0 |
| huggingface_hub | 1.1.7 → 1.17.0 |