dfrokido/jina-v5-text-nano-e8-snap-1024

jina-v5-text-nano — E8 Snap Head (1024-dim)

E8 lattice projection head trained on top of a frozen jinaai/jina-embeddings-v5-text-nano backbone. The head expands 768-dim float embeddings to 1024-dim E8 lattice coordinates — enabling O(1) semantic lookup in LatticeMemory.

MTEB STS Results

Task	Float baseline	E8 Snap Head	Delta
STSBenchmark	0.9445	0.9185	-0.0260
STS13	0.8948	0.8711	-0.0237
SICK-R	0.9197	0.8952	-0.0245
STS17	0.8835	0.8604	-0.0231
STS16	0.8687	0.8500	-0.0187
STS15	0.9281	0.9153	-0.0128
STS12	0.8534	0.8408	-0.0126
BIOSSES	0.8744	0.8619	-0.0125
STS22	0.7030	0.6965	-0.0065
STS14	0.8891	0.8929	+0.0038
10-task mean	0.8759	0.8602	-0.0157

STSBenchmark 0.9185 places this model top 10 globally on the MTEB STS leaderboard (260 submitted models as of 2026-06-04).

What This Is

The backbone is fully frozen. The head learns to map 768-dim encoder output onto the nearest E8 lattice point in 1024 dimensions, preserving cosine similarity while producing addresses that can be indexed in an integer hash table.

• Architecture: OutputOnlyE8Head(input_dim=768, output_dim=1024, hidden_dim=1024)
• Training: STS-B train/val pairs, 5 epochs, AdamW lr=2e-4, batch 16
• Inference: frozen jina backbone → E8 head → L2-normalised 1024-dim output

Usage

from sentence_transformers import SentenceTransformer
from liora_core.embed.small_model_e8_head import load_head_checkpoint
from huggingface_hub import snapshot_download

head_dir = snapshot_download("dfrokido/jina-v5-text-nano-e8-snap-1024")
head, _ = load_head_checkpoint(head_dir)

backbone = SentenceTransformer(
    "jinaai/jina-embeddings-v5-text-nano",
    trust_remote_code=True,
    model_kwargs={"default_task": "text-matching"},
)

import torch
texts = ["semantic search", "vector retrieval"]
with torch.no_grad():
    embs = backbone.encode(texts, convert_to_tensor=True, task="text-matching")
    e8_embs = head(embs, snap=True)   # (N, 1024) E8-snapped

Links

• Demo: LatticeMemory
• GitHub: sangmorg1-debug/e8-Project
• Base model: jinaai/jina-embeddings-v5-text-nano