ABOUT US

About ajairu.dev: Bespoke Software for UK SMEs

A software development studio built on 27+ years of enterprise platform experience. Now bringing that expertise to UK SMEs who want software that fits their business, not the other way round.

ajairu.dev is a bespoke software development studio founded by Toby Callinan, a former CTO at Fabric Fintech with 27 years in software engineering. The studio builds custom software for UK SMEs with 10 to 250 employees, delivering fixed-price projects with full source code ownership and no vendor lock-in.

01

It Starts With How Your Business Actually Runs

Every engagement begins the same way: a conversation about your business, not our technology. Where do your people spend their hours? Which tasks get done twice because two systems do not talk? What breaks when you win a big order?

That is how we build software that fits. Not by scanning for places to sell you a platform, but by understanding how the work flows and finding the points where a well-built system changes real numbers. Sometimes the answer is a bespoke build. Sometimes it is a smarter integration of what you already own, and we will say so.

By the time anything gets built, it has already been tied to an outcome: hours returned, errors removed, orders out the door faster.

A ajairu.dev engineer listening to a UK SME business owner in a first discovery meeting
UK office colleagues working confidently with a custom-built system once manual admin work is automated
02

Then We Kill the Work Nobody Should Be Doing

Every business has them. The copy-paste between two systems that someone does forty times a day. The invoice chased by email every Friday. The same customer details typed into three places. The spreadsheet rebuilt from scratch each month because that is the only tool that fits.

That is what bespoke software removes. Data entered once and flowing everywhere it is needed. Quotes, invoices, and reports generated from the same source of truth. Your team keeping the judgment and losing the drudgery.

We are not precious about how it gets built. If configuring an existing tool solves the problem, we will configure it. When nothing on the market fits your process, that is where a bespoke build earns its keep.

03

And We Insist the Numbers Add Up

Here is the uncomfortable truth about custom software: it only earns its keep if the business case is real. A build that costs more than the problem it solves is not an asset, it is an expensive hobby.

That is why ROI is not an afterthought here, it is the brief. Before we build anything we estimate, in writing, what the work should return: hours saved, licence fees removed, orders processed faster. After it goes live we measure against that estimate and report the gap, honestly, whether it flatters us or not.

If a build cannot articulate a credible payback, we would rather tell you that than take your money. Most of the time the numbers work: a bespoke platform that replaces £50,000 a year of SaaS subscriptions pays for itself within 12 to 18 months, and everything after that is yours.

A consultant and a UK managing director reviewing printed cost and return figures together
Different UK workgroups reviewing plans, code and dashboards in a bright modern office
04

One Team, Whatever Stage You Are At

Because we start from your business rather than a product, the work ranges wide. System integration when your tools do not talk to each other. ERP replacement when subscriptions are eating your margin. A bespoke CRM or client portal when off-the-shelf fits at 60%.

Then the ongoing work that keeps it earning: workflow automation, database development, legacy modernisation so old systems stop being a risk, and a fractional CTO when you need senior engineering leadership without a permanent hire.

One senior team across the whole range. Explore the full set of services and prices, published upfront.

A founder-led team, built around your outcomes

ajairu was founded by Toby Callinan, who has spent 27+ years leading software engineering teams and building platforms that solve real business problems. Over that career, the work has spanned the full spectrum: small businesses figuring out their first systems, mid-market companies scaling their operations, and large enterprises like Aviva, Jaguar Land Rover, and NHS Digital where the stakes and the complexity are at their highest.

Most recently, Toby was CTO at Fabric Fintech, which was acquired by Aviva in late 2023. At Aviva, he led a 45-person cross-functional group that delivered Aviva's first customer-facing generative AI project, taking it from concept to a 1,000-customer pilot in just six months.

That project worked because it was built with discipline: clear use cases, proper architecture, and a team that understood both the technology and the business it was serving. It also showed what happens when any of those pieces are missing. Software bolted on as an afterthought fails. Software without governance creates risk. Software without business context creates tools nobody uses.

The experience left a conviction: the engineering that makes enterprise software work is not exclusive to enterprises. The principles transfer. The budgets do not have to. What SMEs need is a team that has done it at scale, who can translate that experience into something a 30-person business can actually afford and use.

That is what this studio does. Fixed-price engagements. Plain English. Working software you own, not slideware you rent.

Recognition: UK Fintech Awards, Tech of the Year 2024. MoneyFacts Pension Innovation Award 2024.

The Team Behind the Outcomes

Senior people, small by design, measured on what your business gains.

Senior Only

Every person who touches your project has shipped production software in real businesses, not just portfolios. Enterprise discipline, SME pace.

Your Outcome, Our Metric

We define success in your numbers before we start: hours returned to your team, licence fees removed, orders processed faster. Then we report against it monthly.

Care About the Bit After Go-Live

Most software projects fail after launch, not before. We monitor, fix, and improve what we build, and we stay reachable long after the invoice is paid.

Software that works the way you do

What We Believe About Software

Three principles that guide every engagement. We call them The Ownership Standard.

Software Follows the Business

Your software should work the way your business works, not the way a vendor decided it should. We build around your actual processes, not a template. If off-the-shelf software fits your workflow better than bespoke, we will tell you to buy it. We only build when custom is the right answer.

Ownership Over Dependency

Too many software providers build systems that only they can maintain. We do the opposite. Every engagement includes full source code, documentation, team training, and deployment rights. You should be able to run and extend what we build without us in the room. If you cannot, we have not finished the job.

Honesty Over Hype

Bespoke software is not always the right answer. Some businesses are better served by off-the-shelf tools. Some problems are not big enough to justify a custom build. We will tell you that, clearly and early, before you spend money. The £2,000 technical consultancy exists specifically to find out whether bespoke makes sense before you commit to a £50,000 build.

Cut maintenance costs, keep the knowledge

How We Work

Every engagement is fixed-price, agreed upfront, with clear deliverables. No open-ended billing, no surprise invoices, no scope creep billed at premium rates.

Toby leads every project directly. The same person who scopes the work does the work. AI-accelerated development tools help move faster, but every line of code is reviewed and owned by someone who understands it. AI helps build faster. It does not replace engineering judgement.

You own everything we build. Full source code, documentation, and training are included as standard, not sold as an add-on. When the engagement ends, your team can run and extend the work independently.

Learn more about how we work or explore our services and pricing.

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