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Large Language Models

LLM Development Services

LLM development services that go beyond ChatGPT wrappers. We build custom large language model integrations, fine-tuned models, and RAG systems that solve real business problems. Our team combines LLM engineering expertise with honest guidance on what these models can and cannot do in production.

Beyond ChatGPT Wrappers

Most LLM applications are thin wrappers that could be replaced by a well-crafted prompt. We build systems with genuine value: custom knowledge retrieval, domain-specific fine-tuning, production-grade reliability, and architectures that handle what raw APIs cannot.

Common LLM Pitfalls

  • ChatGPT wrappers that add little value over the raw API
  • LLM apps that hallucinate critical business information
  • Generic prompts that produce inconsistent outputs
  • No strategy for handling sensitive or proprietary data

Our Approach

  • Custom architectures that solve specific business problems
  • RAG systems grounded in your actual data sources
  • Engineered prompts tested across thousands of edge cases
  • On-premise and hybrid deployment options for data control

LLM Development Capabilities

From integration to deployment, we handle the full spectrum of large language model development.

LLM Integration Services

Connect GPT-4, Claude, Llama, Mistral, or other models to your applications. We handle API orchestration, fallback logic, cost optimization, and response caching for production workloads.

LLM Fine-Tuning Services

Custom model training on your domain data. Fine-tuning improves accuracy, reduces costs, and creates models that understand your terminology and context. We handle data preparation, training, and evaluation.

RAG Implementation

Retrieval-augmented generation that grounds LLM responses in your documents. Vector databases, chunking strategies, and semantic search that make models accurate for your specific use case.

Prompt Engineering

Systematic prompt development for consistent, reliable outputs. We test prompts against edge cases, optimize for cost and latency, and create evaluation frameworks for ongoing improvement.

Model Selection Consulting

Guidance on choosing between OpenAI, Anthropic, open-source models, or custom solutions. We evaluate tradeoffs between capability, cost, latency, and data privacy for your requirements.

On-Premise LLM Deployment

Run open-source LLMs within your infrastructure. Full data control, no external API calls, compliance-friendly architecture. We handle model optimization for your hardware.

Model Selection Guidance

Different tasks need different models. We help you choose based on capability, cost, and your specific requirements.

When to Use GPT-4 / Claude

Complex reasoning, nuanced tasks, high-stakes outputs. Higher cost but stronger capability. Good for customer-facing applications where quality matters most.

When to Use Smaller Models

High-volume, well-defined tasks. Classification, extraction, summarization with clear patterns. Lower cost, faster latency, often fine-tunable for your domain.

When to Fine-Tune

Consistent formatting needs, domain-specific terminology, cost optimization at scale. Fine-tuning trades upfront investment for better per-request economics.

When to Build RAG

Answers need to reference your proprietary data. Knowledge bases, documentation, internal wikis. RAG keeps models current and grounded in facts you control.

Security & Privacy

LLM deployments need careful attention to data handling, cost controls, and production reliability.

Data Privacy Options

Choose between cloud APIs with enterprise agreements, private endpoints, or fully on-premise deployment. We architect solutions that match your data classification requirements.

Input/Output Filtering

Validation layers that prevent prompt injection, detect sensitive data leakage, and ensure outputs meet your compliance standards. Guardrails built into the architecture.

Cost Controls

Token budgets, caching layers, and model routing that prevent runaway API costs. Monitoring and alerting so you never get surprised by a bill.

Latency Optimization

Streaming responses, response caching, model selection based on task complexity. User experiences that feel responsive even for complex LLM operations.

Our Development Process

LLM projects fail when teams skip validation. We prototype fast and test assumptions before scaling.

1

Requirements Analysis

Understand your use case, data sources, accuracy requirements, and constraints. We determine whether LLMs are the right solution and which approach fits.

2

Architecture Design

Design the system architecture: model selection, RAG vs fine-tuning, deployment model, integration points. Technical decisions based on your specific requirements.

3

Prototype & Validate

Build a working prototype fast. Test with real data, measure accuracy, validate assumptions. Iterate based on actual performance, not theoretical capabilities.

4

Production Deployment

Harden for production: error handling, monitoring, cost controls, scaling. Deploy with confidence knowing the system handles edge cases gracefully.

Why Hexmount for LLM Development

LLM engineering requires more than API knowledge. It needs production experience and honest assessment of capabilities.

Beyond Wrappers

We don't build thin UI layers over ChatGPT. We engineer LLM systems that solve problems the raw API cannot: custom knowledge, consistent outputs, domain expertise.

Honest About Limitations

LLMs hallucinate. We tell you when accuracy requirements exceed what current models can deliver. RAG, fine-tuning, or hybrid approaches to mitigate real risks.

Production Engineering

Demo code is easy. Production LLM systems need error handling, cost controls, latency optimization, and graceful degradation. We build systems that run reliably at scale.

Tiger Team Velocity

Working prototypes in weeks, not quarters. Our distributed team delivers LLM solutions while others are still writing requirements documents.

Ready to Build Your LLM Solution?

Tell us about your LLM project. Custom integration, fine-tuning, RAG implementation, or model selection guidance. We build large language model solutions that deliver real business value.

We choose projects where LLMs are the right solution. Let us assess your use case together.