Custom Large Language Model Development Services With AI-Powered Consulting

Build enterprise-grade large language models tailored to your business logic, data, and workflows. Keel's AI-powered consulting team guides you from initial architecture through to production deployment — delivering custom LLMs that integrate with your existing tech stack, scale with confidence, and give your operations team a genuine competitive edge.

AI engineers collaborating on a custom large language model development project using multiple screens

Our Custom LLM Development Services

From architecture design to production deployment, we deliver end-to-end LLM solutions built precisely for your business needs.

Custom LLM Architecture

Design and build large language model architectures from the ground up, tailored to your domain, data structure, and operational requirements — not generic off-the-shelf templates.

Fine-Tuning & Training

Fine-tune foundational models on your proprietary datasets to produce highly accurate, domain-specific AI that understands your industry terminology, workflows, and business context.

LLM Integration & Deployment

Seamlessly integrate your custom LLM into existing tools, APIs, and tech stacks. Deployed on scalable serverless infrastructure so your model performs reliably at any volume.

AI Strategy Consulting

Work with our experienced consulting team to define your AI roadmap, identify high-impact use cases, and build a long-term strategy that aligns LLM capabilities with your business goals.

Model Evaluation & Optimisation

Continuously monitor, benchmark, and refine your LLM's performance post-deployment using structured evaluation frameworks, ensuring accuracy and reliability improve over time.

Data Pipeline Engineering

Build robust, secure data pipelines that feed your LLM with clean, structured, and compliant training data — fully integrated with your existing data infrastructure and governance policies.

Software engineers reviewing an LLM development pipeline and deployment workflow on a whiteboard

Our 5-Step Custom LLM Development Process

Discovery & AI Strategy Alignment

We begin with a deep-dive consulting session to understand your business objectives, existing data landscape, and target use cases. This ensures every decision — from model selection to deployment architecture — is grounded in measurable business outcomes.

Data Audit, Preparation & Pipeline Build

Model Architecture Design & Fine-Tuning

Integration, Testing & Staged Deployment

Ongoing Evaluation, Optimisation & Support

Trusted By Innovators

Client Success Stories

See how forward-thinking businesses have transformed their operations with custom AI solutions built by Keel.

"Keel is incredibly powerful. Three days writing code and it all just works from the first attempt! The Schema allows for super easy and intuitive data modelling, particularly around the relationship syntax with all foreign keys sorted. I also just love the DevEx! It's well thought-out and far superior to..."

Jay

"Keel's built-in permission engine is incredibly secure and powerful — No other service does it this well!"

Jay

"Keel is truly one of the most obvious wins I've ever seen in the Ops world"

Usman Mahomed

"Keel is incredibly powerful. Three days writing code and it all just works from the first attempt! The Schema allows for super easy and intuitive data modelling, particularly around the relationship syntax with all foreign keys sorted. I also just love the DevEx! It's well thought-out and far superior to..."

Jay

"Keel's built-in permission engine is incredibly secure and powerful — No other service does it this well!"

Jay

"Keel is truly one of the most obvious wins I've ever seen in the Ops world"

Usman Mahomed

"Keel is incredibly powerful. Three days writing code and it all just works from the first attempt! The Schema allows for super easy and intuitive data modelling, particularly around the relationship syntax with all foreign keys sorted. I also just love the DevEx! It's well thought-out and far superior to..."

Jay

"Keel's built-in permission engine is incredibly secure and powerful — No other service does it this well!"

Jay

"Keel is truly one of the most obvious wins I've ever seen in the Ops world"

Usman Mahomed
The Keel Difference

Why Choose Keel for Custom LLM Development?

We bring a rare combination of deep engineering rigour, real-world operations experience, and AI consulting expertise to every engagement.

Operators First

Founded by operators who built custom software at scale, we design LLMs around real business workflows — not theoretical AI use cases.

Full Ownership

You own your model, your data, and your infrastructure — no vendor lock-in, no black-box systems you can't inspect or iterate on.

Production-Ready Fast

Our code-first, engineering-best-practices approach means your custom LLM moves from scoping to production deployment in weeks, not months.

Backed by Serious Investors

Supported by Earlybird and LocalGlobe, leading European tech investors — giving you the confidence of working with a well-funded, credible AI engineering team.

The Team Behind Keel

Seasoned operators and engineers who have built and scaled complex software systems.

Keel was founded in 2021 by three former executives from Echo — Europe's fastest-growing online pharmacy, later acquired by Pharmacy2U. As CEO, CTO, and CPO, the founding team built custom software that shipped 50,000 medicines to 600,000 customers daily, growing the business to $130 million in annual revenue. That first-hand experience of building mission-critical, highly regulated software at scale is the lens through which Keel approaches every custom LLM and AI consulting engagement. In 2024, Keel raised $6 million in seed funding from Earlybird and LocalGlobe, backing a platform built to give operators everywhere flexible, powerful tools they truly own. When you engage Keel for LLM development, you work with a team that has lived the operational complexity you're trying to solve.

Founded 2021Built by operators who scaled a $130M business on custom software
$6M Seed FundingBacked by Earlybird and LocalGlobe, leading European tech investors
Weeks to ProductionCustom LLM solutions designed to go live in weeks, not quarters

Frequently Asked Questions

What is large language model development?

Large language model (LLM) development is the process of designing, training, fine-tuning, and deploying AI models capable of understanding and generating human language. It involves selecting a base model architecture, preparing domain-specific training data, fine-tuning the model on that data, and integrating the resulting system into real-world applications such as internal tools, customer-facing products, or automated workflows.

What is the difference between LLM and GPT?

How long does it take to build a custom LLM?

Do I need my own training data to build a custom LLM?

Will I own the custom LLM Keel builds for me?

How does Keel ensure data privacy and compliance during LLM development?

Can a custom LLM integrate with my existing tools and software?

What ongoing support does Keel provide after the LLM is deployed?

Still Have Questions About Custom LLM Development?

Speak directly with our AI consulting team for a no-obligation discovery call.

Certified & Trusted

Awards and Recognition

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ICO Registered

Registered with the UK data protection authority for compliant data handling.

Keel $6M seed funding badge from Earlybird and LocalGlobe investors

Seed Funded 2024

Backed by Earlybird and LocalGlobe, leading European venture investors.

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Engineering Best Practices

Built on open-source foundations with end-to-end type safety and version control.

Ready to Build Your Custom LLM?

Tell us about your project and our AI consulting team will be in touch to schedule a discovery call. Whether you're starting from scratch or looking to enhance an existing AI system, we'll help you find the right path forward.

Contact Us Today

For immediate assistance, feel free to give us a direct call at You can also send us a quick email at bobbi@keel.xyz