---
language: en
library_name: lf4
license: mit
pipeline_tag: sentence-similarity
tags:
- lf4
- lf4-static-embedding
- static-embedding
- 4-bit
- quantized
- code-search
- tool-search
- embedding
- codebase
- semantic-search
---
# Vortex-Embed-4.7M

`Vortex-Embed-4.7M` is an ultra-lightweight, **4-bit quantized static sentence embedding model** designed for high-throughput semantic code search and tool retrieval. Delivering a 256-dimensional space within a **4.7 MB** footprint, the model completely bypasses heavy deep learning frameworks like PyTorch or Hugging Face Transformers, making it ideal for edge computing, local IDE plugins, and resource-constrained CLI tools.

This model is deployed as the native, default embedder inside [**vortexa**](https://github.com/OEvortex/vortexa)—the open-source AST-aware codebase indexing and semantic search engine.

---

## ⚡ Key Highlights
* **Zero Heavy Dependencies:** Built strictly on NumPy, Safetensors, and Tokenizers. No PyTorch, no execution graphs, no CUDA requirements.
* **Aggressive Compression:** Compressed **6.4×** via LF4 block-quantization while retaining **99.69%** cosine similarity relative to the unquantized FP32 baseline.
* **Blazing Fast Execution:** Sub-millisecond inference (~0.15ms per text string) with linear search scaling.

---

## 📊 Performance Benchmarks

### Quantization Fidelity & Speed
All metrics evaluated on a commodity x86 CPU baseline.

| Metric | Target Value | Notes |
| :--- | :--- | :--- |
| **Cosine Preservation (vs FP32)** | `0.9969` | Near-zero degradation in vector geometry |
| **Mean Squared Error (MSE)** | `0.257` | Absolute error tracking across the vocabulary |
| **Inference Latency** | `~0.15ms` | Per single text encoding execution |
| **Cold Boot / Load Time** | `~144ms` | Disk serialization to memory initialization |
| **Local Search Latency** | `14.6ms` | P50 latency across 2,707 indexed code chunks |
| **Tool Search Accuracy** | `100%` | 15/15 strict functional tool-intent matches |

### Architectural Efficiency Comparison
Why choose a quantized static embedding over a traditional Transformer-based bi-encoder architecture?

| Architectural Feature | Vortex-Embed-4.7M (Static) | BGE / BERT-Base (Transformer) |
| :--- | :--- | :--- |
| **Inference Latency** | **🚀 0.15ms** | ~50.0ms |
| **Cold Start Latency** | **🚀 144ms** | ~5000ms |
| **On-Disk Footprint** | **🚀 4.7 MB** | ~400+ MB |
| **Hardware Prerequisite** | **Commodity CPU** | Dedicated GPU Highly Recommended |
| **Domain Performance** | **Optimized for Code / Tools** | General Text Semantics |

---

## 🛠️ Architecture & Quantization Details

The model utilizes a learned token-to-embedding static matrix combined with custom **LF4 per-block quantization**. Sentences are processed via tokenization, sequential row-lookup with inline dequantization, mean pooling, and final L2 normalization.

### Structural Topology
```text
vocab_size = 29,528 | dimensions = 256 | bits = 4 | block_size = 32

```

### Tensor Layout Matrix

The underlying weights are stored safely inside a standard `.safetensors` dictionary container:

| Tensor Target | Data Type | Dimensions / Shape | Functional Description |
| --- | --- | --- | --- |
| `embedding_packed` | `uint8` | `(29528, 128)` | 4-bit packed array space (stores two 4-bit values per byte) |
| `embedding_scales` | `float16` | `(29528, 8)` | High-precision floating-point per-block scale multiplier |
| `embedding_zeros` | `float16` | `(29528, 8)` | High-precision floating-point per-block zero-point offset |

---

## 🚀 Quickstart Installation & Usage

### Prerequisite Environment

```bash
pip install numpy safetensors tokenizers

```

### 1. Seamless Codebase Indexing (Via `vortexa`)

For turnkey directory indexing, search, and MCP support, use the official core engine:

```bash
pip install vortexa

```

```python
from vortexa.core.indexer import CodebaseIndexer

# Native integration: vortexa resolves and loads Vortex-Embed-4.7M out of the box
indexer = CodebaseIndexer(root='.')
stats = indexer.index()

# Execute high-speed vector retrieval across code chunks
results = indexer.search('find CSV parser or file tokenizer', top_k=5)

```

### 2. Standalone Low-Level Inference (No Torch Pipeline)

For custom applications or minimal CLI tools requiring zero framework overhead:

```python
from lf4_model import LF4StaticEmbedding

# Streamlined serialization layer
model = LF4StaticEmbedding.from_pretrained('VTXAI/Vortex-Embed-4.7M')

# Encode source text directly into normalized NumPy arrays
embeddings = model.encode(['search the web', 'read file'])

# High-performance analytical matrix search mapping
scores, indices = model.search(query_emb, doc_emb, top_k=10)

```

### 3. Sentence-Transformers Framework Compatibility

If you prefer running within standard ML pipelines, use the modern native static backend:

```bash
pip install sentence-transformers

```

```python
from sentence_transformers import SentenceTransformer

# Load using the explicit static processing engine
model = SentenceTransformer('VTXAI/Vortex-Embed-4.7M', backend='static')
embeddings = model.encode(['search the web', 'read file'])

```

---

## 📜 Citation & Attributions

If you leverage this model or the `vortexa` engine in technical research, production environments, or industrial applications, please reference the repository utilizing the following BibTeX schema:

```bibtex
@software{vortex-embed-4.7m,
  title  = {Vortex-Embed-4.7M: High-Performance 4-Bit Static Embedding Topology},
  author = {VortexAI},
  year   = {2025},
  url    = {[https://huggingface.co/VTXAI/Vortex-Embed-4.7M](https://huggingface.co/VTXAI/Vortex-Embed-4.7M)}
}

```