Custom LLM Development Services

Your Business Deserves a Smarter Conversation.

Generic AI is like hiring someone who read every book but never worked a day in your industry. Our custom LLM development services build language models that know your business, speak your language, and slot into the way your people work.

18+
Years shipping real products
850+
Engineers ready to build
30+
Countries trust our work
Your data. Your rules. Your model.

Tell us the task you want a model to own. We'll tell you plainly whether an LLM is the right fit, and what it would take.

Cloud-Native Hero – 20-Minute Chat
No sales calls. No slide decks. A straight answer, honestly.
GPT-4oLLaMA 3MistralClaudeGeminiRAGFine-tuningVector SearchLangChain GPT-4oLLaMA 3MistralClaudeGeminiRAGFine-tuningVector SearchLangChain
Custom LLM Development Services

Ready-Made AI Is Clever. Custom LLM Development Makes It Brilliant.

ChatGPT knows the world. It does not know your return policy, your top clients, or the way your team writes an email. We fix that. We build a model that knows your business inside out, so every answer feels like it came from your best employee, not a search engine.

Trained on your world

Built on your actual documents, products, and processes, not the public internet everyone else shares.

Your data

Fits your workflow

Slotted into the tools your team already uses every day, so nobody has to learn a new system.

Integrated

Scales with you

Built to grow as your ambitions do, without a rebuild every time your usage climbs.

Ready to grow

Private by default

Secure enough for your most sensitive information, running under your rules and your control.

Private
What We Actually Build

Six Ways Our LLM Application Development Makes You Smarter

Our custom LLM development services cover every stage, whether you are starting from a blank page or already halfway there. One team, from your first sketched idea to the day your users love it.

Build It From Scratch

When off-the-shelf is not enough, we design models from the ground up, trained on your data alone, so every answer sounds like your company wrote it.

From scratch

Make It Yours

Already on GPT or LLaMA? Good start. We shape it to your world so it stops sounding like a generic chatbot and starts sounding like your smartest teammate.

Fine-tuning

Teach It What You Know

Your company has years of knowledge in documents, wikis, and manuals. We connect your model to all of it so it can actually use what you already have.

RAG & knowledge

Let It Handle the Boring Stuff

Chasing data, writing the same email for the tenth time, filling in forms. We build tools that take those tasks off your team's plate so they can focus on work that needs a human.

Automation

Fits Right In

No one wants to learn a new system. We wire your model into the tools your team already lives in, whether that is your CRM, your ERP, or your internal dashboard.

Integration

We Stay After We Launch

Going live is not the finish line. We deploy, monitor, and keep improving your model long after launch, because the best AI gets better with time.

Managed
How We Work

Simple Steps. Zero Smoke and Mirrors.

We have done this enough times to know what works. Here is exactly how we get from your idea to something your team actually uses.

01
Listen

We Listen

Before we write a single line, we sit with your team and ask real questions. What problem keeps you up at night? What would success look like six months from now?

02
Prepare

We Prepare

Good models need good data. We dig into what you have, clean it up, and turn it into something a model can actually learn from.

03
Build

We Build

This is where the magic happens. We choose the right model, train it on your data, and fine-tune it until it behaves exactly as expected.

04
Test

We Test

We break it before your users do. Accuracy, speed, edge cases, and safety all get stress-tested before anyone sees a single response.

05
Launch

We Launch

Launch day is just the beginning. We stay close, watch how it performs in the real world, and keep making it better as your business evolves.

Under the Hood

We Pick the Right Tool. Not the Trendy One.

We are not loyal to any single platform. We are loyal to what works for you. Here is the toolkit we draw from depending on what your project needs.

Foundation Models
The engines we build on.
Frameworks
The tools that wire it together.
Cloud & Infra
Where it runs, reliably.
Data & Search
How it finds the right answer.
Foundation models, chosen for the job
We match the model to your problem, whether that is a frontier API, an open model you can host yourself, or something custom built on your data.
GPT-4o OpenAILLaMA 3 MetaMistral Mistral AIGemini GoogleClaude AnthropicFalcon TIICohere CohereCustom Built for you
Why Bother Going Custom?

Off-the-Shelf AI vs Private LLM Development

Off-the-shelf tools are impressive at parties. But when your customers ask a real question, or your team needs a real answer, the cracks show. Here is why custom wins.

Off-the-Shelf AICustom LLM by BS23
Trained on your business dataTrained on public internet dataBuilt on your documents and domain knowledge
Answers in your brand voiceGeneric, inconsistent toneSounds like your company, not a chatbot
Data privacy and controlData often processed externallyRuns inside your environment, your rules
Industry and compliance fitNo awareness of your regulationsBuilt with your compliance requirements in mind
Integration with your systemsLimited, often needs workaroundsDesigned to connect with what you already use
Ongoing improvementVendor controls updates and directionWe tune and improve it alongside your team
Cost at scalePer-query costs grow fast with volumePredictable costs on infrastructure you own
Why Teams Choose Us

The LLM Development Company That Stays With You After Go-Live

Most vendors disappear when things get complicated. We do not. One team, one point of contact, from messy data to production and long after.

One Team. Full Accountability.

We do not outsource the hard bits. One team, one point of contact, from messy data to production deployment. If something breaks, we own it.

Accountable

Your Data Stays Yours.

ISO 27001 certified. We treat your data like it belongs to you, because it does. Every model comes with controls that keep sensitive information where you need it.

Secure

We Ship Fast. No Drama.

850 engineers and 18 years of shipping under pressure means we move fast without cutting corners. Most teams are surprised how quickly we reach something usable.

Fast

We Are in Your Timezone.

Offices in the USA, UAE, Germany, and Malaysia mean you are never waiting until morning for an answer. When your team is at their desk, so are we.

Global overlap
ISO 27001 CertifiedCMMI Level 3AWS Advanced PartnerMicrosoft Solutions PartnerGoogle Cloud Certified18 Years Enterprise Track Record
850+
Engineers
100+
Technologies
30+
Countries
5
Global Offices
We Know Your World

Enterprise LLM Development That Already Knows Your Industry

We do not learn your industry on your time. We already know the questions that keep your team up at night and the rules you cannot afford to break.

Fintech and Banking

Finance and Banking

Compliance headaches, document mountains, and clients who want instant answers. We build tools that handle all three.

Healthtech and Pharma

Healthcare and Life Sciences

From clinical documentation to patient communication, we help healthcare teams spend less time on admin and more time on care.

Retail and Commerce

Retail and Ecommerce

Customers want fast, helpful answers. We help you give them that without hiring an army of support staff.

Enterprise and SaaS

Enterprise and Operations

Thousands of documents. Dozens of departments. One model that helps your team find answers, review contracts, and report upward without the usual chaos.

Pick Your Flavour

Two Ways to Work With Us. Both Get Results.

Some clients hand us the keys. Others want us riding shotgun. Either way works. Here is how to decide which fits you.

You Hand Us the Keys
We Own It · from start to finish

Tell us what you want to achieve. We handle everything else, from architecture decisions to launch day. You stay in the loop, we do the heavy lifting.

  • Clear milestones and delivery dates from day one
  • A dedicated team that only works on your project
  • Honest updates, not just the good news
  • Full documentation and a smooth handover when we are done
Let Us Build It
Most flexible
You Stay in the Driver Seat
We Ride Shotgun · your team, our engineers

Your team knows the business. We know the technology. Together, you ship faster and smarter than either of us could alone.

  • Senior engineers who adapt to your team, not the reverse
  • Flexible, scale up or down as the work demands
  • Your tools, your standups, your way of working
  • We are up to speed quickly and honest when things need changing
Let Us Join In
You Have Questions. Good.

We Have Heard These Before. Here Are Honest Answers.

No fluff. No sales spin. If you still have something on your mind after reading these, just send us a message.

Do we need mountains of data before we can even start?

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Not at all. Some of the most effective models we have built started with a surprisingly small, well-structured dataset. We will look at what you have and tell you plainly what is possible. If you do not have enough, we will tell you that too.

How long before we actually see something working?

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A focused tool built on an existing model can be ready in weeks. Something bigger and fully custom takes longer. Either way, we give you a real timeline before work starts, and we stick to it.

Our data is sensitive. How do we know it is safe with you?

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ISO 27001 certified. Your data is used to build your model and nothing else. We never share it, sell it, or use it to train any other system. If you need the model to run entirely inside your own infrastructure, we can do that too.

You ship it and disappear, right?

+

We have never ghosted a client and we are not going to start with you. We stay involved after launch, watch how the model performs, fix anything that drifts, and keep improving it as your business changes.

Will this actually connect to the software we already rely on?

+

In almost every case, yes. We have wired models into CRMs, ERPs, internal dashboards, customer portals, and plenty of custom-built systems. Your team keeps working the way they always have. The model just makes it better.

We are not a tech company. Are we even the right kind of client for you?

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Some of our favourite clients are non-tech teams who knew exactly what problem they were trying to solve but had no interest in how the technology worked. You bring the business knowledge. We bring the engineering. That combination almost always beats a purely technical team working alone.

What if a language model is not actually what we need?

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Then we will tell you. Honestly. We have talked clients out of building custom models when a simpler solution made more sense. We would rather lose a project than build something you do not need.

Do Not Just Take Our Word for It

Real Words From Real People We Built For

We are not going to paste in five-star ratings and call it trust. Here is what the people we actually built for had to say.

They told us what was possible, what was not, and then delivered exactly what they said they would.
Burned before by vendors who over-promised, this team was refreshingly honest from the first call.
SR
Sarah R.Head of Digital Operations · Healthcare
Compliance review used to take two days before any decision. Now it takes twenty minutes.
That time goes back to our people, and they use it well.
MK
Marcus K.VP of Operations · Financial Services
These guys spent three weeks just listening. By the time they built, they understood our customers better than some of our own team.
Most agencies start designing on day one. The result showed the difference.
JP
Jamie P.Chief Product Officer · Consumer Brand
Ready for Custom LLM Development Services?

Tell Us Your Problem. Our Custom LLM Development Team Will Take It From There.

No sales calls. No slide decks. Just a straightforward conversation about what you are trying to do, what is getting in the way, and whether we are the right team to fix it.

Book a Free Chat
No commitmentAn honest opinionStraight answers, on the call