Senior Solutions Engineer
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
You will serve as the technical expert for customers and internal stakeholders. You will design integration solutions, resolve complex technical issues, and guide customers from sandbox integration through public launch. You will partner on technical demos, security and RFP questionnaires, and solution architecture. You will also provide strategic support to key accounts and improve the customer journey through project go-live.
Requirements
- Deep understanding of API concepts, security mechanisms, and integration patterns
- Strong knowledge of SaaS architecture, cloud computing conventions, and modern web applications
- Coding skills in Java
- Ability to write database queries in SQL
- Familiarity with software frameworks and client-server architecture
- Experience with Postman, Claude Code, Codex or another AI harness, a database client, and an OpenAPI demo tool
- Ability to explain complex technical concepts to non-technical stakeholders
- AWS knowledge is a plus
- Python scripting is a plus
Responsibilities
- Assist signed customers with technical integrations from sandbox to public product launch
- Lead requirements gathering, provide technical recommendations, conduct testing, and oversee initial transaction monitoring
- Partner with Sales and Account Management on technical product demos, security questionnaires, RFP questionnaires, and integration solutions
- Provide strategic technical support for important, high-volume, and strategic accounts
- Identify account growth opportunities
- Improve business processes across the customer journey from sales discovery to project go-live
- Help define and shape local standard operating procedures