Senior Lead Software Engineer- Back End- Madrid- Digital Assets

Behind every investment is a person with ambitions, motivations and values. While we know that every client is unique, they come to J.P. Morgan Personal Investing for the same reason: our straightforward and transparent approach to investing, and the trust that 150 years of J.P. Morgan heritage brings. J.P. Morgan Personal Investing offers award-winning investments, products and digital wealth management services to over 275,000 investors in the UK. We built the business with innovation as a core part of our ethos to give consumers the confidence and clarity to make informed investment decisions and achieve their financial goals. As an engineer at J.P. Morgan Personal Investing, you will be part of a team with great ambitions. We aim to build a first-class suite of mobile and web apps to provide the best investment experience for our clients. Our team is at the heart of this venture, focused on getting smart ideas into the hands of our customers. We're looking for people who have a curious mindset, thrive in collaborative squads, and are passionate about building quality software that has a big impact in a rapidly changing environment. By their nature, our people are also solution-oriented, commercially savvy and have a head for fintech. We work in tribes and squads that focus on specific products and projects. Job Responsibilities Build and maintain integrations with digital asset providers and infrastructure (on ramp/off ramp), optimising for security, stability and escalability. Work with the Product team to understand user needs and follow an Agile SDLC to develop and deliver product features. Our stack is Java/Springboot with a bit of Kotlin, DynamoDB, Aurora/MySQL and AWS. Participate with the rest of the team in designing how our architecture needs to evolve to meet our needs. We use ADRs as part of our decision-making process, and our architecture is microservices running on Kubernetes with heavy use of Kafka and event-driven design — a natural fit for streaming real-time market data and trade events. Partner with Compliance, Risk, and Operations to ensure integrations meet regulatory, security, and controls requirements relevant to digital assets (e.g., transaction monitoring, wallet screening, key-management controls). Take ownership of tasks from the estimation stage right through to release and post-production. Identify, troubleshoot and resolve existing or newly identified prioritised defects — with particular care around anything touching balances, order flow, settlement, or asset movement, where correctness is non-negotiable. Write tests for all code you deliver and adhere to best practices/standards, ensuring high-quality code. Given the financial and irreversible nature of on-chain transactions, expect a strong emphasis on deterministic, well-tested, and auditable code paths. Take ownership of, or assist others with, releases and associated processes (we try to deploy as often as possible). Participate in code reviews, ensuring high code quality and continuous development and learning for yourself and your colleagues. Be someone who enjoys knowledge sharing and is keen to attend and participate in the many skill-share sessions we regularly hold across the wider Engineering department. Propose/contribute/collaborate on Technical Initiatives — improving and evolving the existing codebase and toolset. Help ensure we focus on solving the essence of the problem rather than merely dealing with the symptoms. Required qualifications, capabilities and skills English working proficiency is a must; you will be working with the team in London. Hands-on experience with exchange, brokerage, custody, wallet, or settlement systems for digital assets. Drives adoption and governance of approved AI-assisted engineering practices across teams to improve code quality, delivery speed, and operational outcomes (e.g., AI-assisted code review/refactoring, test acceleration, release readiness, incident/root-cause analysis), while establishing measurable validation standards (secure coding, peer review, automated testing) and promoting reuse of proven patterns and automation within the SDLC/TLM toolchain. Applies knowledge of tools within the Software Development Life Cycle toolchain, including approved AI-assisted development and automation capabilities, to improve the value realized by automation at scale. Solid working understanding of digital-asset fundamentals: blockchains, wallets, public/private keys and signing, transactions and fees (e.g., gas), tokens (e.g., ERC-20 and equivalents), and the distinction between custodial and non-custodial models. Experience with smart contracts and/or reading on-chain data (e.g., Solidity, web3 libraries, node providers such as Infura/Alchemy, or running your own nodes). Familiarity with how connectivity with blockchain networks and nodes work (e.g., Bitcoin, Ethereum and EVM-compatible chains, Layer 2s), including transaction construction, broadcasting, monitoring for confirmations/reorgs, and reconciliation of on-chain and off-chain state. Awareness of the regulatory and compliance landscape for digital assets (e.g., AML/KYC, travel rule, market-abuse considerations). You have a product engineer mindset and a track record of delivering high-quality software that adjusts to business and product needs to provide a great user experience in a timely manner. Experience with a JVM language (Java/Scala/Kotlin) and Springboot. Experience designing systems from scratch as well as evolving existing architectures to achieve new goals, both serverless and managed in the cloud. Hands-on experience designing and implementing event-driven architectures with different message brokers, including Kafka — ideally applied to high-throughput, low-latency data such as market or trade feeds. Experience integrating with third-party financial or trading APIs (REST, WebSocket, and/or FIX), including handling rate limits, authentication/signing schemes, reconnection, and idempotency. Experience with monitoring and alerting to maintain a production environment — with an appreciation that in trading/crypto contexts, downtime and latency have direct financial consequences. Good understanding of REST and what it means to work with APIs. Experience with Git flow. Good communication skills; you can work well within a delivery team and manage interactions with other parts of the organisation, such as Product, Operations, Compliance, and Risk. Curious about new ways of working and open to different approaches and ideas. Proactive and willing to help others and put forward ideas. Preferred qualifications, capabilities and skills — nice to haves Familiarity with trading concepts such as order books, order types, matching, market/limit orders, and settlement lifecycles. Experience with DynamoDB and/or Aurora. Experience in the FinTech, trading, or digital-asset sector. Experience developing a multi-country product with multiple localizations and currencies (crypto or fiat). Show us your Github/Stack Overflow/app portfolio — bonus points for crypto/blockchain projects! #ICBCareers #ICBEngineering