maxbsdv/LEO-seamless-m4t-v2-large-Roverplastik

LEO Seamless-M4T v2 Large Roverplastik Adapter

This repository contains the LoRA adapter for LEO, a domain-adapted multilingual translation model for Roverplastik technical content.

The adapter is fine-tuned from:

facebook/seamless-m4t-v2-large

It is intended for technical translations among Italian, English, French, and Spanish, with a focus on window systems, installation manuals, insulation, monoblocchi, cassonetti, airtightness, and related building-envelope terminology.

Model Details

• Base model: facebook/seamless-m4t-v2-large
• Adapter type: PEFT LoRA
• Training framework: PyTorch Lightning + QLoRA
• Precision: bf16 mixed precision, 4-bit base model loading
• Hardware used: NVIDIA RTX 4090
• Released adapter path: leo_hf_release

Training Checkpoint

The exported adapter was selected from the best validation checkpoint:

seamless-m4t-v2-large-finetuned-epoch=05-val_loss=0.54.ckpt

The benchmark was run directly from this .ckpt before export. The Hugging Face adapter export is used only for release and deployment.

Evaluation

Benchmark command:

python scripts/leo.py benchmark

Evaluation set:

• data/gold/test_set.csv
• 1005 translation samples
• directions among Italian, English, French, and Spanish

Global results:

Metric	Base Seamless-M4T	LEO adapter	Absolute delta
BLEU	0.3173	0.5806	+0.2633
chrF	0.5320	0.7382	+0.2061
METEOR	0.4749	0.7255	+0.2505

Regression check:

152 / 1005 samples regressed by chrF = 15.1%

The model shows a strong global improvement over the base model, especially on technical terminology and domain-specific phrasing. Remaining regressions are mostly concentrated in selected non-Italian cross-language directions and in minor function-word differences.

Usage

The adapter is designed to be loaded with PEFT on top of facebook/seamless-m4t-v2-large.

Example with the project CLI:

python scripts/leo.py infer \
  --src-lang eng_Latn \
  --tgt-lang ita_Latn \
  --text "This window profile ensures excellent air tightness."

Expected smoke-test output:

Questo profilo di finestra garantisce un'eccellente tenuta all'aria.

The public Space uses the ADAPTER_PATH environment variable to point to this adapter repository.

Intended Use

Use this model for assisted translation and review of Roverplastik-style technical material:

• installation manuals
• technical datasheets
• product catalog text
• building-envelope documentation
• multilingual internal validation workflows

The model is not a substitute for human review in legal, certified, contractual, or safety-critical documentation.

Limitations

• The benchmark set includes synthetic and curated examples; final production quality should still be checked by domain experts.
• Some regressions remain versus the base model, especially in selected cross-language directions.
• The model may occasionally alter small function words or produce acceptable paraphrases that score lower under character-level metrics.
• The model is optimized for the Roverplastik/building-envelope domain, not for broad general-purpose translation.

Framework Versions

• PEFT 0.18.0
• Transformers 4.57.3