Role Overview We are seeking an experienced Smart Contract Developer to support a major Core Banking transformation using Thought Machine Vault Core. The role focuses on designing, developing and maintaining Lending and Savings products using Vault Smart Contracts. You will translate complex business requirements into robust, testable product logic and work closely with Product Managers, Business Analysts, Architects, QA and engineering teams. Key Responsibilities Develop and maintain Vault Smart Contracts for Lending and Savings products. Translate business requirements into scalable, maintainable product logic. Implement interest, accruals, repayments, fees, payment allocation, balances and lifecycle events. Support product migration from legacy systems to Vault. Collaborate with Product, Business Analysis, Architecture and Engineering teams. Develop automated tests covering business rules, edge cases and regression scenarios. Participate in code reviews and technical design discussions. Investigate defects and support functional, integration, migration and production testing. Validate and reconcile financial calculations between legacy systems and Vault. Support releases and produce technical documentation. Follow engineering, security, governance and regulatory standards. Essential Skills & Experience Strong software development experience, preferably Python. Hands-on experience with Thought Machine Vault Smart Contracts. Experience developing and testing complex financial/business logic. Good understanding of banking products and financial calculations. Experience with automated testing/TDD, Git, CI/CD and modern engineering practices. Strong analytical, problem-solving and communication skills. Experience working in multidisciplinary Agile teams. Strong understanding of Volt Core, including: Smart Contracts and Vault APIs Posting instructions Balances and dimensions Scheduled events and hooks Interest accrual/application Account lifecycle management Desirable Experience Lending and/or Savings product implementation. Legacy-to-Vault product migration. Interest rates, repayment schedules, fees, overpayments/underpayments, deposits, withdrawals, maturity and account closure. Financial event streams and downstream accounting/reporting. Reconciliation between legacy and target banking platforms. UK financial services or other regulated banking environments. Microservices, event-driven and cloud-native architectures. Jira, Confluence and Agile/Scrum.Disclaimer: This vacancy is being advertised by either Advanced Resource Managers Limited, Advanced Resource Managers IT Limited or Advanced Resource Managers Engineering Limited ("ARM"). ARM is a specialist talent acquisition and management consultancy. We provide technical contingency recruitment and a portfolio of more complex resource solutions. Our specialist recruitment divisions cover the entire technical arena, including some of the most economically and strategically important industries in the UK and the world today. We will never send your CV without your permission. Where the role is marked as Outside IR35 in the advertisement this is subject to receipt of a final Status Determination Statement from the end Client and may be subject to change