Solution Architect (Java, AI-native backend, FinTech)
Unlimit is a London-based global fintech providing cross-border payment processing, business accounts, banking-as-a-service, card issuing, and crypto/stablecoin payment infrastructure.
About Unlimit
Founded in 2009, Unlimit operates a global financial-services platform for businesses, combining payment processing, local and international payment methods, multicurrency business accounts, banking-as-a-service APIs, card issuing, payment rails, and digital-asset on/off-ramp capabilities. The company is headquartered in London and operates across multiple continents.
Skills
Candidate Availability
Required and preferred rules are kept separate and reflect the wording in the original posting.
About the Role
Lead solution design and architecture for scalable, resilient backend systems supporting card acquiring, wallets, crypto, and BaaS products. Partner across product, engineering, DevOps, QA, and data teams to define modular designs, guide cloud migration, improve platform modernization, and integrate AI capabilities.
Requirements
- 6+ years of experience in architecture roles, preferably in fintech or high-availability distributed systems.
- Experience designing scalable backend systems in AWS or hybrid cloud environments.
- Strong hands-on background in Java backend development, DevOps, or cloud infrastructure.
- Deep understanding of distributed systems, event-driven architectures, microservices, CI/CD, and observability.
- Experience with Kubernetes, Terraform, and GitLab CI/CD.
- Experience driving system design reviews across multiple teams.
- Strong stakeholder communication and technical-business alignment skills.
- Comfort working in fast-paced, cross-functional LATAM, EU, and APAC environments.
- Experience integrating AI/ML components, AI pipelines, agent-based integrations, or MLOps.
- Awareness of AI-driven engineering practices and emerging AI technologies.
- Experience using LLMs, AI-assisted development tools, or automation frameworks.
- Background in financial services, payment gateways, acquiring, digital wallets, or regulated environments.
Responsibilities
- Own solution design for backend systems powering card acquiring, wallets, crypto, and BaaS products.
- Design and maintain AI-native, cloud-agnostic architecture aligned with security, scalability, and compliance standards.
- Translate business needs into modular architectural designs with cross-functional stakeholders.
- Create documentation, solution diagrams, interface contracts, and component specifications.
- Contribute to API design and service decomposition.
- Guide AWS-based cloud migration and infrastructure evolution using Kubernetes, GitLab CI/CD, and Terraform.
- Ensure zero-downtime deployments, automated rollbacks, and scalable horizontal patterns.
- Conduct architectural reviews and technical assessments with delivery teams.
- Drive architectural maturity and platform modernization across engineering functions.
- Identify technical debt and long-term design risks and propose mitigations.
Benefits
- Opportunity to drive AI-native backend transformation at scale.
- Exposure to card processing, crypto, wallets, and BaaS products.
- Work in a global company with an engineering culture, agile mindset, and flat hierarchy.
- Collaboration with international teams focused on architecture, resilience, and innovation.
- Support for asynchronous cross-timezone collaboration.
