What You’ll Be Doing
- At Unlimit, backend engineering is evolving into agent engineering.
- You won’t simply write Java or Kotlin services. You will design and implement AI agents that build, refactor, test, and optimize those services — agents that actively participate in the software lifecycle rather than passively assisting it. Instead of creating microservices only for human consumption, you will architect systems that are self-describing, agent-consumable, and machine-operable by design.
- Your APIs will not just be called — they will be reasoned about. AI systems will understand their contracts, constraints, and behaviors. You will help construct a full pipeline from requirements to deployment, where validation agents automatically enforce PCI-DSS rules, regulatory constraints, scalability requirements, and architectural standards. Compliance will not be a checklist at the end — it will be continuously verified by intelligent systems embedded in the flow.
- And it won’t stop at build-time automation. You will develop autonomous monitoring agents capable of detecting anomalies, diagnosing root causes, and triggering corrective workflows in production environments operating at global financial scale. Traditional microservices will be redesigned into agent-ready execution units — modular, observable, introspectable components that machines can safely evolve.
- You will collaborate closely with DevOps, Data, and AI teams who are building their own agents, uniting these systems into a coordinated multi-agent ecosystem that powers our financial infrastructure.
- The outcome is simple but transformative: your code will not only serve production. It will serve the agents that run production.
Qualifications You Will Bring
- A mindset that sees AI not as a tool, but as a new execution layer. You design systems where agents act, validate, and evolve software — not just assist humans.
- Proven experience integrating LLMs, MCP servers, and multi-agent systems into real engineering workflows — not experiments, but production-oriented pipelines.
- Hands-on work with frontier models such as Claude Opus 4.x, GPT-5.x Codex or similar — using them for structured reasoning, code generation, validation, orchestration, and system design.
- Strong understanding of context engineering and token economics — including prompt architecture, reusable memory patterns, retrieval layers (RAG), persistent state management, and optimizing token consumption for long-horizon agent workflows.
- Ability to design guardrails for autonomous systems — validation layers, policy enforcement, compliance checks, circuit breakers, and architectural constraints that keep AI-driven systems stable and safe.
- 4+ years of strong Java (Spring/Spring Boot) or Kotlin experience in production environments — enabling you to validate, constrain, and refine what AI agents generate.
- Deep understanding of distributed systems and scalable backend architectures in high-throughput, low-latency environments.
- Experience designing resilient microservices capable of operating under financial-grade reliability and regulatory requirements.
- Comfort building observable, introspectable, automation-friendly systems — because agents cannot safely operate opaque services.
- Strong communication skills to collaborate effectively in a global AI-first organization where engineering, data, compliance, and product intersect.
Nice to have:
- Experience in fintech, payments, or banking systems.
- Experience working with AWS services and infrastructure.
- Familiarity with containerized deployments (Docker, Kubernetes) and CI/CD pipelines.
- Exposure to AI-enabled systems or interest in integrating intelligence into applications.
- Background in event-driven architectures and message-based systems (Kafka, RabbitMQ).
Why This Role Exists:
- Software developers will not disappear. But software development as we know it will.
- We are transforming Unlimit into an AI-first, agent-native fintech platform.This role sits at the center of that transformation.
- Build financial infrastructure for AI agents
- Replace manual engineering with autonomous systems
- Design platforms where machines are first-class users
- Work at the frontier of fintech + AI
Skills Required
- 4+ years of hands-on experience with Java (Spring, Spring Boot) or Kotlin
- Proven experience designing, developing, and debugging RESTful web services and microservices
- Confident knowledge of Git, Gradle, and CI/CD tools
- Solid understanding of software architecture and scalability in cloud environments
- Ability to troubleshoot complex issues
- Strong English communication skills
What We Do
From London to Singapore and from San Francisco to São Paulo, we help businesses enter new markets, explore new industries, and reach new milestones. We are driven by a deep-seated determination to be the best possible partner for our customers – giving you the support you need to capitalize on a world that’s changing at breakneck speed. Our mission is to provide innovators with a convenient and simple financial interface that enables payments to flow freely and invisibly across borders. We offer a wide range of services, including payment gateway, card acquiring, business accounts, card issuing, alternative payment methods, and more. That’s the reason why we are called Unlimit: we provide unlimited growth opportunities for our customers, freeing them from the payment constraints. Unlimit - Borderless Payments







