NextBrick
AI

Open Source LLM Consulting

Deploy, fine-tune, and operate open-source large language models on your own infrastructure — GPT-OSS-20B, GPT-OSS-120B, Llama 4, Llama 3, Gemma 3, and more — with Nextbrick's AI engineers.

Overview

The open-source large language model ecosystem has matured rapidly, delivering models that rival proprietary frontier systems across a wide range of tasks — from code generation and document analysis to conversational AI and complex reasoning. For organizations that require data sovereignty, regulatory compliance, cost predictability, or deep model customization, open-source LLMs offer a compelling path to production AI without vendor lock-in or per-token API costs.

Nextbrick's Open Source LLM Consulting practice helps enterprises select, deploy, fine-tune, and operate open-source language models on their own infrastructure — whether on-premises GPU clusters, private cloud, or dedicated cloud instances. Our AI engineers bring production experience with the leading open-source model families including OpenAI GPT-OSS-20B and GPT-OSS-120B, Meta Llama 4 and Llama 3, Google Gemma 3, Mistral, DeepSeek, and Qwen. We combine model expertise with infrastructure engineering skills to deliver self-hosted AI platforms that are performant, cost-efficient, and production-ready.

Model Selection & Benchmarking

Choosing the right open-source model is the first and most consequential decision. Nextbrick evaluates models against your specific use cases using domain-relevant benchmarks, measuring quality (accuracy, coherence, instruction following), latency (time-to-first-token, tokens-per-second), cost (GPU memory, compute hours), and safety (toxicity, hallucination rates, compliance with your content policies).

We maintain an internal evaluation harness that tests models across your representative prompts and datasets, comparing GPT-OSS-20B and GPT-OSS-120B against Llama 4 Scout and Maverick, Llama 3 70B and 405B, Gemma 3 27B, Mistral Large, and DeepSeek-V3 — providing clear, data-driven recommendations on which model (or combination of models) delivers the best quality-cost tradeoff for your workloads.

Self-Hosted Deployment & Inference Infrastructure

Deploying open-source LLMs at production scale requires specialized inference infrastructure. Nextbrick designs and implements high-performance serving architectures using the leading inference engines: vLLM for PagedAttention-based serving with high throughput and low latency, Text Generation Inference (TGI) by Hugging Face for production-grade model serving with built-in safety features, and GGUF-quantized models served via llama.cpp for CPU and consumer-GPU deployments that minimize hardware costs.

We design GPU cluster topologies optimized for LLM inference, configuring NVIDIA A100, H100, and H200 GPUs (or AMD MI300X) with NVLink, InfiniBand, and high-bandwidth networking for tensor-parallel and pipeline-parallel inference. For smaller models and edge deployments, we implement quantized serving (GPTQ, AWQ, GGUF) that delivers strong quality at a fraction of the hardware cost.

Our deployment architectures include autoscaling (scaling replicas based on request queue depth), health checking, graceful model loading and unloading, A/B traffic routing for model comparison, and observability integration with Prometheus and Grafana.

Fine-Tuning & Domain Adaptation

When base models don't meet your quality bar out of the box, Nextbrick fine-tunes open-source LLMs on your proprietary data to achieve domain-specific accuracy. We implement supervised fine-tuning (SFT) using curated instruction-response pairs from your domain, parameter-efficient methods (LoRA, QLoRA) that adapt models without full-weight retraining — reducing GPU cost and training time by an order of magnitude, reinforcement learning from human feedback (RLHF) and Direct Preference Optimization (DPO) for aligning model outputs with your quality and safety standards, and continued pre-training on domain corpora for specialized knowledge injection.

Our fine-tuning pipelines run on your infrastructure using frameworks like Hugging Face Transformers, Axolotl, and LLaMA-Factory, with experiment tracking (Weights & Biases, MLflow) and evaluation suites that measure improvement against baseline models.

On-Premises & Air-Gapped Hosting

For organizations in regulated industries — financial services, healthcare, defense, government — data may never leave the organization's network perimeter. Nextbrick designs on-premises LLM hosting architectures that run entirely within your data center or private cloud, with no external API calls. We configure GPU servers, container orchestration (Kubernetes with GPU operator), model registries, and inference endpoints that operate in fully air-gapped environments.

We implement security controls including network isolation, mTLS encryption, role-based access control, audit logging, and content filtering to meet compliance requirements for HIPAA, SOC 2, FedRAMP, ITAR, and internal data-governance policies.

Model Routing & Cost Optimization

Not every request needs a 120-billion-parameter model. Nextbrick implements intelligent model-routing architectures that direct simple queries to smaller, faster models (GPT-OSS-20B, Gemma 3 9B, Llama 3 8B) and route complex tasks to larger, more capable models (GPT-OSS-120B, Llama 4 Maverick, Llama 3 405B). This tiered approach can reduce inference costs by 60-80% while maintaining quality where it matters.

We also implement semantic caching (returning cached responses for semantically similar queries), prompt compression to reduce input token counts, and batching strategies that maximize GPU utilization during high-traffic periods.

RAG & Application Integration

Open-source LLMs become most valuable when integrated into applications. Nextbrick builds Retrieval-Augmented Generation (RAG) pipelines that ground model responses in your organization's data — connecting self-hosted LLMs with vector databases (Qdrant, Milvus, pgvector), document processing pipelines, and enterprise knowledge bases. We design agentic architectures where LLMs orchestrate tool calls, database queries, and API interactions to complete complex multi-step tasks.

Our application-integration layer includes structured output parsing (JSON mode, function calling), streaming response delivery, conversation-state management, and guardrails that enforce output quality, format compliance, and safety policies.

Managed Operations & Model Lifecycle

Nextbrick offers managed operations for self-hosted LLM platforms. Our services include 24/7 monitoring of inference latency, throughput, GPU utilization, and error rates, model updates and version management as new releases and fine-tuned checkpoints become available, evaluation regression testing to confirm that model updates maintain or improve quality, infrastructure scaling to accommodate traffic growth, and security patching for the inference stack and underlying OS. We deliver dashboards and monthly reports that give your leadership visibility into AI platform performance, cost, and usage trends.

Why Choose Nextbrick for Open Source LLMs

Nextbrick combines deep AI/ML expertise with the infrastructure engineering skills needed to run LLMs reliably at scale. We've deployed open-source models across industries — from financial services to healthcare to manufacturing — and we understand the unique challenges of self-hosted AI: hardware planning, model optimization, security compliance, and operational maturity. Whether you're deploying your first open-source model or scaling an existing platform, Nextbrick delivers the expertise to make self-hosted AI a strategic advantage. Contact us to discuss how we can help you succeed with open-source large language models.

Industry References Informing Our OSS LLM Approach

  • OpenAI GPT-OSS launch
  • Hugging Face openai/gpt-oss-20b
  • OpenAI model docs for GPT-OSS-20B
  • Fireworks: GPT-OSS deployment notes
  • Clarifai: running local AI coding agents

Open Source LLM Consulting Market Extract (In-App Summary)

The following points were extracted and consolidated from the provided source URLs and rewritten for Nextbrick pages:

  • openai/gpt-oss-20b · Hugging Face — We’re on a journey to advance and democratize artificial intelligence through open source and open science.
  • OpenAI gpt-oss 20b & 120b: Overview & Benchmarking Info — Use state-of-the-art, open-source LLMs and image models at blazing fast speed, or fine-tune and deploy your own at no additional cost with Fireworks AI!

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