Model reference · open weights

mLateOn-unsupervised

mLateOn-unsupervised is an open-weight embedding model from lightonai, listed in the AxForge catalogue. AxForge can bring it up on EU-owned hardware for you on request — with the licence handled where one is required.

Embeddings lightonai 1 variants 715 downloads/mo
Request this model on EU hardware All served models Not on the shared API today — deployed on request.

About

What mLateOn-unsupervised is

[](https://lighton.ai) [](https://www.linkedin.com/company/lighton/) [](https://x.com/LightOnIO) 📚 Collection | 📝 Multilingual Blog | 📝 English Blog | 📝 Paper 🎯 TL;DR: The intermediate multilingual ColBERT checkpoint produced by Stage 1 only (unsupervised contrastive pre-training) of the mLateOn pipeline, trained on a multilingual dataset with 2.8B query–document pairs across nine languages (including 25% cross-lingual pairs). Released as a strong starting point for your own supervised fine-tuning, knowledge distillation, or downstream adaptation. About the mDenseOn / mLateOn Family With DenseOn and LateOn, we demonstrated that an open, carefully curated data recipe can match closed-data retrieval models on English. mDenseOn and mLateOn extend this recipe to multilingual, long-context, and code retrieval. Rather than independently collecting multilingual corpora from scratch (which would be expensive, uneven across languages, and hard to curate at the same quality), we applied the translate-train approach: machine-translating our validated English data into eight target languages (French, German, Italian, Spanish, Portuguese, Swedish, Norwegian, and Arabic) and adding cross-lingual pairs for cross-lingual alignment. For more information, please read our multilingual models blog post, our English models blog post and our paper. mLateOn-unsupervised mLateOn-unsupervised is the output of the first stage of the mLateOn training pipeline. It has been pre-trained on a large, filtered multilingual corpus of approximately 2.8B query–document pairs across nine languages (including 25% cross-lingual pairs) using in-batch contrastive learning, but has not yet been fine-tuned with mined hard negatives. For most production use cases, you should use the fully-trained mLateOn instead. This unsupervised checkpoint is intended for: - Researchers studying what each pipeline stage contributes in a multilingual setting - Practitioners who want to fine-tune on their own domain-specific or language-specific data - Distillation experiments where you want to start from a strong but un-aligned multilingual base - Anyone running their own ablations on hard-negative mining strategies or t

Summarised from the published model card. Read the full card on the HuggingFace links below.

Specifications

What it is

Makerlightonai
TypeEmbedding models
Parameters (lead)307M
Context8k tokens
Variants1
Runs withPyLate
Based onjhu-clsp/mmBERT-base
Released2026-07-09
Popularity715 downloads / month
Likes6
LicenceOpen weights

How it works

How embedding models work

Your textsentence / documentEncodermaps meaningVectorlist of numbersAn embedding model turns text into a vector, so similar meanings sit close together — the basis of search and RAG.

Variants

Sizes & precisions

Open weights ship in several sizes and precisions. One page, all the variants — pick the one that fits your GPU. VRAM figures are estimates from model size.

VariantParamsPrecisionVRAMFits 16 GBWeights
mLateOn-unsupervised307MBF16~0.7 GBWeights ↗

Using it via the API

Call it like any OpenAI endpoint

Once AxForge deploys mlateon-unsupervised for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (mlateon-unsupervised below is illustrative; you get the exact model name on deployment.)

$ curl -sS https://api.axforge.ai/v1/embeddings \
  -H "Authorization: Bearer $AXFORGE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"mlateon-unsupervised","input":"text to embed"}'

Details

Languages, data & research

Languages

en fr de it es pt sv no ar code

Tags

PyLate safetensors modernbert ColBERT sentence-transformers sentence-similarity feature-extraction multilingual code search en fr de it es

Papers

Licence

Open weights

Open weights under apache-2.0 — commercial use is permitted. Deploy it on AxForge EU hardware on request. Read the licence ↗

Sources

Weights & code

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