Enterprise LLMs: A Case Study in Self-Hosting Llama 3
For many enterprises, sending sensitive legal or financial data to a public API is a non-starter. This case study details how we deployed a fine-tuned Llama 3 70B model on internal infrastructure to create a secure Legal Assistant.
The Challenge: Data Sovereignty
Our legal team needed an AI to summarize contracts, but our compliance policy strictly forbade sending client data to OpenAI or Anthropic.
- The Constraint: All inference must happen within our VPC.
- The Goal: GPT-4 level reasoning on legal texts.
The Solution: Self-Hosted Llama 3
We chose Meta’s Llama 3 70B for its balance of high reasoning capability and permissive license.
1. Infrastructure
We deployed the model on AWS SageMaker using g5.12xlarge instances (4x A10G GPUs).
- Engine: vLLM for high-throughput serving.
2. Fine-Tuning (QLoRA)
We didn’t just use the base model. We fine-tuned it on a dataset of 5,000 internal legal contracts using QLoRA (Quantized Low-Rank Adaptation).
- Cost: ~$400 in compute time.
- Result: The model learned our specific “Legal Dialect” and internal formatting standards.
Results & Impact
| Metric | GPT-4 (API) | Self-Hosted Llama 3 |
|---|---|---|
| Privacy | Non-Compliant | 100% Private |
| Cost per 1k Tokens | $0.03 | $0.004 (at utilization) |
| Legal Accuracy | 88% | 94% (after fine-tuning) |
Conclusion
The era of “one model to rule them all” is ending. By self-hosting open weights models, enterprises can achieve better privacy, lower costs, and higher accuracy for domain-specific tasks.