Zantabri. Book a review

Software engineering & delivery partner · UK

Software you can verify, not just trust.

Backend, cloud and integration engineering for businesses and consultancies. We practise specification-driven delivery: what correct means is agreed before anything is built, and what gets built is checked against it.

Book a free technical review See the work
  • 15+ years senior engineering
  • Backend, cloud & integration
  • Subcontract or white-label

Specification-driven delivery

What that gets you

We start by working with your stakeholders to establish the problem you actually want fixed. What comes out of that is the standard the work is then held to — and three things follow from it.

Before a line is written

You approve what will be built

The intended behaviour is written down in language your business can read and challenge — while changing it is still cheap, rather than after it has been built the wrong way.

In review

Correctness stops being an opinion

What was built is checked against what was agreed. Whether something is right gets settled by the record rather than by whoever is most senior in the room.

With AI in the loop

Generated code meets the same bar

Where models write code — and on modern projects they do — they work to the same agreed definition of correct, and the output is held to it like any other.

Correctness should be something you can check — not something you argue about in code review.

The practice behind it is
the part we walk you
through in person

Selected work

Four deliveries, in our own words

Zantabri is a new practice. The engagements below were delivered by our founder, Oladapo Animashaun, in senior and lead engineering roles at the organisations named — not as client work for Zantabri. Each is described as the role allowed.

Sky · Lead Engineer

Delivered early

Adapting a platform for a strategic partner

Situation
Sky needed to onboard a strategically important partner whose operating model differed significantly from the workflows its platform already supported. The requirements were complex, and it was not yet clear whether the platform could accommodate them.
What we did
Led the engineering delivery: translating the partner's requirements into practical technical solutions, adapting the platform's behaviour with the team, and demonstrating that it could support the partner's workflows.
Outcome
The required changes landed ahead of schedule, giving the business confidence in the solution and contributing to the partner's successful onboarding.

Sky · Lead Developer

Shared API blueprint

A shared standard for REST APIs

Situation
REST APIs were designed differently across engineering teams, and even within a team there were no established rules for structure and behaviour. Services were harder to integrate, and engineers had little common guidance when creating or improving APIs.
What we did
Defined practical REST API design standards and advocated their adoption across teams — a shared blueprint for new APIs and a reference for improving existing ones, structured so the same conventions could be supplied to AI agents working with those APIs.
Outcome
A clear set of rules teams could use to make API design more consistent, improve interoperability and raise design maturity — and a specification AI-assisted development could work from.

CI&T · Senior Developer

One week early

Protecting downstream systems from CMS change

Situation
An external content management system and the systems consuming its data used different JSON schemas, and those schemas could change independently. Connecting downstream systems directly to the CMS data model risked breaking them whenever that model changed.
What we did
Designed and implemented an anti-corruption layer that translated CMS data into the format downstream systems expected, creating a clear boundary between the two data models so changes to one did not propagate into the other.
Outcome
The integration was resolved a week ahead of schedule. The boundary reduced coupling, protected downstream consumers from CMS model changes, and made the integration easier to maintain.

NetPlus Advisory · Head of Engineering

15,000 TPS at peak

A payment platform built for scale

Situation
The business had outgrown its original fintech platform. Built with PHP and MySQL as an MVP, it had limited technical sophistication and security vulnerabilities that were costly to manage. It needed a stronger foundation for reliable, high-volume payment processing.
What we did
Designed and implemented a SaaS payment gateway to replace the legacy platform, integrating with the Nigerian interbank settlement system over ISO 8583, with security, fault tolerance and transaction throughput treated as core architectural requirements.
Outcome
The platform processed more than 15,000 transactions per second at peak, giving the business a more secure and resilient foundation for delivering payment services at scale.

Capability

What we build, and how we plug in

Backend & API engineering

  • REST API design and development
  • Java, Spring Boot and Kotlin
  • Microservices and distributed systems
  • Authentication and authorisation
  • Event-driven integrations
  • Legacy and third-party integration

Cloud & platform engineering

  • AWS cloud architecture
  • Docker and containerised workloads
  • Kubernetes
  • Infrastructure as Code with Terraform
  • CI/CD pipelines
  • Observability and operational readiness

Systems integration

  • API and third-party integrations
  • Operational-system integration
  • Data synchronisation
  • Integration architecture
  • Workflow automation
  • SaaS platforms and bespoke systems

Ways to work together

Project delivery
We take responsibility for a defined engineering workstream or technical capability.
Subcontract engineering
Senior engineering capability behind your organisation's client delivery, under your brand.
Technical delivery partnership
Working alongside your team across architecture, engineering, testing and deployment.
Prototype to production
Turning prototypes and proofs of concept into secure, maintainable production systems.
Additional delivery capacity
Experienced engineering capability when project demand exceeds your internal capacity.

Core technical capability

Backend
Java · Spring Boot · Kotlin · Node.js · REST APIs · Reactive Systems
Cloud & infrastructure
AWS · Docker · Kubernetes · Terraform · Infrastructure as Code
Engineering
Microservices · Distributed Systems · API Design · OAuth2/OIDC · CI/CD · GitHub Actions
Data
SQL · NoSQL · MongoDB · Data Integration
AI-assisted engineering
OpenAI · Claude · AI-enabled development workflows · Specification-driven development
Frontend
React · JavaScript · TypeScript · Tailwind CSS

No cost, no obligation

A free technical review

Sixty minutes on an architecture you are unsure about, a delivery that is slipping, or an AI prototype that needs to become a production system. You will leave with a written summary of what we would do, and in what order — whether or not you work with us.

We are equally happy operating visibly alongside your organisation or as a subcontract engineering partner behind your own brand.

Telephone
07865 288972

Oladapo Animashaun
Founder / Principal Software Engineer