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<h3>About MoonPay</h3>MoonPay is for builders with something to prove.This isn't a "work on cool crypto stuff" company. It's a high-standards, high-velocity, high-accountability company building the operating system for value movement. If the internet moves information, we move value: crypto, stablecoins, tokenized assets, and whatever comes next. Four offerings make that real: fund, tokenize, trade, and spend. 30M+ customers and 500+ ecosystem partners run on us. Licensed in the U.S. Regulated across the UK, EU, Canada, and Australia.AI is the default operating mode here. It's woven into every role, and we expect you to use it daily. It handles the manual work so you can deliver on what actually matters.You'll thrive here if outcomes excite you more than process, if impact motivates you more than titles, and if you want hard problems, real ownership, and teammates who love winning, building, and doing it together.The bar is high. The pace is real. We're building for what's next, for humans and agents. Recent recognition: <a href="https://www.forbes.com/lists/americas-best-startup-employers/" rel="noopener noreferrer nofollow ugc" target="_blank">Forbes' America's Best Startup Employers 2026 . </a>2nd in Crypto Services on <a href="https://fortune.com/ranking/crypto/" rel="noopener noreferrer nofollow ugc" target="_blank">Fortune's inaugural Crypto 100</a>, <a href="https://www.thetimes.com/best-places-to-work/medium-companies/article/best-medium-companies-2026-hg8f06jrv" rel="noopener noreferrer nofollow ugc" target="_blank">The Sunday Times Best Places to Work</a> two years running.Research has shown that women are less likely than men to apply for this role if they do not have experience in 100% of these areas. Please know that this list is indicative, and that we would still love to hear from you even if you feel that you are only a 75% match. Skills can be learned, diversity cannot.
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<h3>Locations Supported 🌍</h3><ul><li>London, UK</li></ul>Relocation available: NoWork pattern: Hybrid: our teams meets in the office ~1-2 days a week<h3>About the Opportunity</h3>Every transaction we process requires a real-time decision. Declining a legitimate transaction leaves a customer stuck at the point of purchase, while approving a fraudulent one carries a direct cost.This role owns the decisioning system and underlying platform. From the serving path and feature infrastructure to the underlying models and the machinery required to make safe, live updates. You will continuously improve the platform and our day to day workflows, rather than treating these as secondary projects.As a Staff Machine Learning Engineer, you will hold a hands-on technical position. You will be part of a team that builds, ships, and maintains the entire machine learning lifecycle.Our main focus is fraud detection and prevention, an adversarial domain where opponents constantly adapt and feedback arrives in the form of financial impact. Alongside, this we build broader capabilities to enable machine learning across Moonpay.<h3>Lead through ambiguity</h3><ul><li>Turn vague problems into well-defined solutions and bring people with you.</li><li>Set the technical bar through rigorous reviews, clear standards, and lasting engineering habits.</li></ul><h3>Build and scale the platform</h3><ul><li>Develop feature infrastructure across batch, near-real-time, and in-request paths, managing specific freshness budgets for each.</li><li>Maintain alignment between training and serving to ensure models behave in production exactly as they did offline.</li><li>Integrate feedback loops to capture every decision and its outcome, including blocked transactions where results are counterfactual.</li><li>Scale the platform as volume and model complexity grow, ensuring operational load remains manageable.</li></ul><h3>Decide in real time</h3><ul><li>Own the services that score transactions in-flight, inside a hard latency budget</li><li>Design the degraded paths: what we answer when the model can't, and who agreed that policy</li></ul><h3>Ship safely, continuously</h3><ul><li>Mature the replay, shadow and staged-rollout tooling until changing a live model is routine and reversible</li><li>Own models across their lifecycle, from training through to retirement, and catch decay long before losses confirm it</li></ul><h3>About You</h3><h3>Must-have experience and skills</h3><ul><li>Real-time serving. You have built and operated high-availability services that execute within strict latency budgets on critical paths, and you’ve designed robust fallback mechanisms</li><li>Systems thinking. You view the architecture holistically: identifying failure points, managing graceful degradation, and ensuring the system remains responsive even when dependencies fail. You build the feedback loops that allow a system to learn from its own decisions.</li><li>Engineering craft. You write code other people are happy to inherit — tested, typed, and correct when events arrive twice, late, or out of order. Adding the next feature to something you built is fast and painless.</li><li>Pipelines in production. You have owned feature or data pipelines end-to-end, including troubleshooting cases where offline and production metrics diverged and resolving the underlying discrepancies.</li><li>Ambiguity and influence. You've taken a problem nobody had scoped and turned it into work that shipped, and raised the level of the engineers around you while doing it.</li></ul><h3>Nice-to-have experience</h3><ul><li>Decision explainability. You've built systems where the reason for a decision mattered as much as the decision: audit trails, per-layer attribution, llm-driven analyses, or defending a model's behaviour to a non-technical audience.</li><li>Anomaly detection. You have developed systems to detect novel attack patterns and emerging abuse without existing labels, identifying suspicious behavior relative to historical baselines.</li><li>Familiarity with our stack: GCP, BigQuery, Bigtable, Memorystore, Vertex AI, Kubernetes.</li></ul>______________________________________________________________________________________________________<h3>Benefits & Perks 💡</h3><ul><li>💰 Competitive salary package</li><li>🤝 Equity package: financial freedom starts with our employees, so all employees have ownership at MoonPay</li><li>📈 Pay-for-performance equity bonus: those who drive outsized outcomes receive outsized rewards</li><li>🚀 Moonshot award: we honor exceptional impact. 10 employees twice a year, each earning a $250,000 equity grant</li><li>📊Pension: employer contributions from day one</li><li>🎁Employee referral program: refer great people, earn 10K in USDC</li><li>🏝 Flexible Time Off: choose when to work and when to switch off</li><li>🎂 Birthday leave: take the day off to celebrate you</li><li>🍼 Enhanced parental leave: more time with family, no second thought</li><li>🌍 Hybrid working schedule: work fully remotely or from your nearest Moonbase</li><li>🚆 Commuter benefits: public transport to and from the office</li><li>🩺 Private healthcare benefits: to protect you and your loved ones</li><li>🧘 Wellhub wellness membership: access to gyms, studios, classes, and wellness apps in one membership</li><li>🤖 Unlimited enterprise access to the latest AI tools: Claude, ChatGPT, Gemini and whatever's next</li><li>🍱 Lunch credit: meals covered on the days you're in the office</li><li>🪑 Home office setup allowance: build the home office of your dreams</li><li>👛 Remote working allowance: those working fully remotely get a little extra for utilities</li><li>🌕 Monthly product budget and zero-fee crypto transactions</li><li>📚 $1,000 Annual training budget: we support your learning journey</li><li>🎯 High Potential Program: structured development, mentorship, and stretch opportunities</li><li>✈️ Regular remote company offsites: high-impact in-person sessions and hackathons</li><li>🚲 (Ireland) Cycle to Work scheme: tax-efficient bike, gear, and safety kit</li><li>🔌 (UK) EV Salary Sacrifice: lease an electric vehicle through pre-tax salary</li></ul>We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses and identifying potential inconsistencies or verification signals in application materials based on available information. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.

Staff Machine Learning Engineer

<h3>About Plasma</h3>Plasma is building the primary account for global money.Money used to belong to a country. Increasingly, it belongs to a person or business moving through many countries. People and businesses now earn, spend, save, hire and invest across borders. Traditional banks cannot serve this new world.Our first product, Plasma One, is a global money account: a place to receive, hold, send funds in seconds, earn yield and spend with a card in the local economy.Underneath is the Plasma network, built from first principles for stablecoin payments. Stablecoins make dollars faster, cheaper and more reliable to move.Technological revolutions obey power laws. The opportunity is to become where all global money lands first: where income arrives, balances grow, payments move, businesses operate, and new financial products are built.<h3>The Team & <a href="https://x.com/Plasma/status/7719601?s=20" rel="noopener noreferrer nofollow ugc" target="_blank">Our Story</a></h3>We are a global team of founders, operators and engineers, obsessed with building the best products. We work at the cutting edge of financial innovation, using stablecoins to create tools for consumers and businesses.We operate with trust, clarity, and ambition: own your craft, move with urgency, contribute beyond your lane, back your teammates, debate rigorously, and keep raising the bar for what great means.<ul><li>Consumer owns the core Plasma One product experience - onboarding, activation, retention, rewards, tiers, trading, earn, and account management. The team is responsible for growing funded users, engagement, balances, spend, and long-term retention.</li><li>Payments owns the financial infrastructure that powers Plasma - accounts, ledgers, funding, payouts, card issuing, reconciliation, payment orchestration, and currency/rail integrations. The team is responsible for the reliability, scalability, and economics of moving and storing money.</li><li>Business owns the Plasma experience for companies - the operating account for businesses that work globally: onboarding, receiving, holding, and sending money across borders, corporate cards and spend management, and the roles and approvals that keep teams in control of company money. The team is responsible for taking the product from its first business customers to general availability, and for growing the businesses that run on Plasma.</li></ul><h3>The Role</h3>We're looking for a staff+ engineer, backend-leaning but comfortable full-stack, to join one of Plasma's engineering teams and take ownership of that team's hardest technical problems. Our stack is TypeScript across the board - Node.js on the backend and React + React Native for the frontendYou are expected to set technical direction for your team's most critical systems, while partnering with product and, where relevant, other teams at the points where your systems connect.<h3>The Work</h3><ul><li>Own the hardest technical problems inside your team end to end - the ones that need deep judgment, not just execution.</li><li>Set technical direction for your team's core systems: architecture, data models, and standards that hold up as the team scales.</li><li>Design for reliability first: idempotency, consistency, and graceful failure recovery in systems that move or store real money, or that the network depends on.</li><li>Go deep on the backend, but stay full-stack, own the TypeScript service and the data model, and work through the client or API layer when the problem calls for it.</li><li>Define how your team's systems handle the hard edge cases: partial failures, retries, timeouts, reversals, reconciliation gaps - whatever “correct under pressure” means for your team.</li><li>Contribute, architect and improve the frontend systems and integrations wherever necessary</li><li>Raise the technical bar within your team: code standards, testing strategy, monitoring, incident response, and how the team approaches ambiguous problems.</li><li>Mentor other engineers and drive technical clarity on the hardest parts of your team's system.</li></ul><h3>The Bar</h3><ul><li>A staff-level, hands-on engineer with a track record of owning production systems end to end, not just contributing to them.</li><li>Backend-leaning but full-stack: deep expertise building backend services in TypeScript (Node.js), with enough range to work through the client layer when needed.</li><li>Strong instincts around reliability and correctness - you think in systems: state machines, data integrity, observability, operational risk.</li><li>Comfortable taking systems from zero to one, and then scaling them without losing clarity.</li><li>Strong judgment on tradeoffs: speed vs. safety, abstraction vs. control, simplicity vs. flexibility.</li><li>You communicate clearly, write clean code, and can lead through technical decisions without needing to manage people.</li><li>You have very high agency and don’t wait to be told a problem to work on and proactively find new problems to solve</li><li>You make decisions based on data and use data to ground whether solutions work</li></ul><h3>Nice to have</h3><ul><li>Fintech, banking, or crypto-native background.</li><li>Familiarity with stablecoins, custody, settlement, and blockchain transaction lifecycles.</li><li>You’ve been a founder or early employee at a fast-paced, high agency startup</li></ul><h3>What's in it for you</h3><ul><li>Above-market salary for the level of the role, with token compensation.</li><li>A beautiful London HQ with gym access and daily food, for those who thrive in an office environment. Visa sponsorship and relocation support if you're joining from abroad.</li><li>Premium health insurance for you and your family, fully covered by Plasma.</li><li>Monthly wellness budget, whether that's the gym, therapy, sauna, or massage.</li><li>All the tools and tech you need to operate at your best.</li><li>Real ownership and responsibility from day one, with your work shipping to hundreds of thousands of people, moving millions of dollars every day.</li></ul>Data Protection & PrivacyWe are committed to protecting the privacy and security of your personal data. Any personal information you provide during the recruitment process will be processed in accordance with the General Data Protection Regulation (GDPR) and applicable local data protection laws.

Staff+ Software Engineer

<h3>About ARQ</h3>ARQ is one of the fastest-growing fintechs in the world. Our mission is to redefine how people interact with money across borders, building the infrastructure to move value seamlessly. We’re still early in our journey, which means every person who joins shapes the future of our product, culture, and growth. If you’re excited by big challenges, global impact, and the chance to grow fast with a world-class team, ARQ is the place to do it.<h3>What we're looking for</h3>As a Backend Engineer, you’ll design, develop, and maintain scalable, secure, and high-performing backend systems that power our innovative products. You’ll collaborate with a talented team to create solutions that drive financial inclusion and transform the way people manage their money.<h3>What you'll be doing</h3><ul><li>The work will focus on greenfield development and improvement of existing systems</li><li>Projects will include building REST APIs, engineering microservices and evolving a number of systems that our business depends on (e.g. card payments, treasury management, transactions booking, crypto liquidity)</li><li>Our technology stack is based predominantly on Java 25 on the backend with Postgres database</li><li>We rely on Spring Boot for quick and quality delivery</li><li>We have a pragmatic approach to develop our business logic, focusing on clean code, with emphasis on maintainability and fast turnaround with TDD, DDD and continuous integration & delivery</li></ul><h3>What you'll need</h3><ul><li>Demonstrable experience in Backend development, with fluency in Java</li><li>Bachelor's Degree (or above) in Computer Science, Mathematics, Physics, or other Engineering / Science disciplines</li><li>Quick learner with an ambitious and results driven personality, with excellent communication skills (english fluency, verbal and written)</li><li>Track record of building complex products that millions of people use in hypergrowth startups</li></ul><h3>Benefits</h3><ul><li>Competitive salary and benefits </li><li>Stock options, so you own part of what you build</li><li>Discretionary performance bonus</li><li>The latest tools and technology</li><li>A world-class team that will challenge and grow your skills</li><li>The opportunity to help build the best fintech app in Latin America</li><li>Office Policy: 3-4 days a week in-office</li></ul>

Lead Software Engineer(Java)

The world of digital assets is accelerating in speed, magnitude, and complexity, opening the door to new ways for leveraging the blockchain. Fireblocks’ platform and network provide the simplest and most secure way for companies to work with digital assets and it trusted by some of the largest financial institutions, banks, globally-recognized brands, and Web3 companies in the world, including BNY Mellon, BNP Paribas, ANZ Bank, Revolut, and thousands more.Fireblocks is on a mission to enable every business to easily and securely access digital assets and cryptocurrencies. As a leading provider in the digital asset space, we are committed to fostering a diverse and inclusive workforce that mirrors the global clientele we serve.The FinApps Access team at Fireblocks builds the backbone of on-chain access for some of the world’s largest financial institutions and crypto-native organizations. We operate at the intersection of blockchain protocol engineering and enterprise-grade reliability — designing systems that route, protect, and optimize transactions across dozens of chains at scale.You’ll work on mission-critical infrastructure powering DeFi connectivity, multi-chain integrations, transaction execution pipelines, and on-chain data access — with direct impact on how billions of dollars flow through decentralized networks every day.What You’ll Do
- Design and build robust, scalable backend services supporting high-volume on-chain transaction flows across multiple blockchain networks — both EVM and non-EVM.
- Own end-to-end development of backend components and APIs — from architecture decisions to production deployment.
- Lead integrations with DeFi protocols, on-chain data sources, and blockchain nodes across a wide range of chains and ecosystems.
- Research and evaluate emerging blockchain technologies, protocols, and standards to keep Fireblocks at the cutting edge.
- Optimize existing production systems for performance, reliability, and security — reducing latency and increasing throughput.
- Collaborate closely with product, protocol research, and platform engineering teams to deliver high-quality solutions on time.
- Drive features from inception through to delivery at scale, taking full ownership of the product lifecycle.

Full Stack Engineer, Blockchain

<h3>Building the Future of Open Finance</h3>Payward - the parent company behind Kraken, NinjaTrader, Breakout, xStocks, Payward Services and CF Benchmarks - has spent the last 15 years building one of the most modern and globally accessible financial infrastructure platforms in the industry, built to advance an open, global financial system.Before you apply, we encourage you to explore our <a href="https://www.kraken.com/culture" rel="noopener noreferrer nofollow ugc" target="_blank">culture page</a> to understand what drives us and how we work.<h3>The team</h3>Founded in 2011, Kraken is one of the world's longest-standing crypto platforms, trusted by over 10 million individuals and institutions across the globe. It offers spot trading, margin, futures, staking, and OTC services, with products built for both individual investors and institutional clients.We’re looking for a Data Analyst, Product to join our team remotely. The #1 goal of this role is to turn complex data into clear, actionable insights that improve user experience, support the development of new features, deepen engagement, and help leadership make high-impact product decisions. You’ll own end-to-end data management from production-grade pipelines and dbt models to dashboards and metric frameworks for the Pro product team. You'll define north star metrics from the ground up, drive experimentation infrastructure through A/B testing and causal inference, and translate results into clear product recommendations. We're actively building a culture where AI tooling is part of how we work, from LLM-augmented pipelines to GenAI-assisted workflows, and we're looking for people who are excited to grow alongside that.Beyond technical expertise, success in this role depends on being a true business partner who combines data-driven insights with deep knowledge of client retention funnels and user behaviour. You bring experience from environments where data quality has real consequences and where you've had to build the infrastructure, not just use it.The opportunity<ul><li>Operate as a full-stack data analyst within the Pro team, owning your domain completely while collaborating closely with colleagues across the pod.</li><li>Own the design and evolution of dashboards, north star metrics and analytical frameworks that drive decisions at the highest level of the business.</li><li>Build and maintain data infrastructure at scale, from scalable dbt models and production pipelines to full-funnel reporting that powers cross-functional teams.</li><li>Lead experimentation across the Product domain by designing and owning A/B testing frameworks, applying causal inference techniques and turning results into clear, confident recommendations that influence product strategy.</li><li>Influence technical direction across the data team, contributing to how we build, what we prioritise and how we raise the bar on data quality and engineering standards.</li><li>Embed AI tooling into your workflow in ways that have tangible business impact, including LLM-augmented pipelines and GenAI-assisted analytics workflows.</li><li>Deliver insights through clear, data-driven storytelling to technical and non-technical audiences, including senior leadership.</li></ul>What You Bring<ul><li>7+ years of experience in data analytics or analytics engineering, ideally within fintech, payments, financial market or crypto where data quality and scale are non-negotiable.</li><li>You have hands-on experience with advanced trading products and solutions in equities, crypto, or other assets. You either have a professional background working within financial markets or on a trading desk, or you are a professional trader.</li><li>Hands-on experience building and owning production data pipelines, with strong familiarity with dbt and Airflow or equivalent orchestration tools.</li><li>Full mastery of SQL including complex joins, CTEs and analytical functions, alongside strong Python proficiency for pipeline development and analysis.</li><li>Hands-on experience designing and running A/B tests and experimentation frameworks, with the ability to apply causal inference techniques and translate results into clear growth recommendations.</li><li>Demonstrated experience leading cross-functional data initiatives from design to delivery, with measurable business outcomes you can point to.</li><li>Strong communicator who can simplify complex data ideas for both technical and non-technical audiences.</li><li>A degree in a field emphasising analytical rigour such as software engineering, economics or a hard science.</li><li>Based in Canada, the US, the UK or the EU and fluent in English.</li></ul>Nice to haves<ul><li>Experience with LLM-augmented analytics pipelines or AI-assisted workflows in a production environment</li></ul>Unless a specific application deadline is stated in the job posting, applications are accepted on an ongoing basis.Please note, applicants are permitted to redact or remove information on their resume that identifies age, date of birth, or dates of attendance at or graduation from an educational institution.We consider qualified applicants with criminal histories for employment on our team, assessing candidates in a manner consistent with the requirements of the San Francisco Fair Chance Ordinance.<h3>Our commitment</h3>Payward is powered by people from around the world and we celebrate the diverse talents, backgrounds, contributions, and unique perspectives that everyone brings to the table. We hire based on merit, seeking out people with the right abilities, knowledge, and skills for the job. We encourage you to apply for roles where you don't fully meet the listed requirements, especially if you're passionate or knowledgeable about crypto.We may ask candidates to complete job-related skills or work-style assessments as part of our hiring process. These assessments evaluate competencies relevant to the role and are applied consistently across candidates for similar positions. Results are considered alongside experience and interviews, and are not the sole basis for any employment decision.As an equal opportunity employer, we don't tolerate discrimination or harassment of any kind, whether based on race, ethnicity, age, gender identity, citizenship, religion, sexual orientation, disability, pregnancy, veteran status, or any other protected characteristic as outlined by federal, state, or local laws.Stay connected<a href="https://twitter.com/krakenfx" rel="noopener noreferrer nofollow ugc" target="_blank">Follow us on Twitter</a><a href="https://blog.kraken.com/#:~:text=Enter%20your%20email%20address" rel="noopener noreferrer nofollow ugc" target="_blank">Learn on the Kraken Blog</a><a href="https://www.linkedin.com/company/kraken-exchange/" rel="noopener noreferrer nofollow ugc" target="_blank">Connect on LinkedIn</a><a href="https://www.kraken.com/legal/candidate-privacy-notice" rel="noopener noreferrer nofollow ugc" target="_blank">Candidate Privacy Notice</a>

Data Analyst, Product

10 link clicks.

Tether Operations Limited

You will own the inference backbone behind QVAC's local AI stack: the C++ systems layer that makes models run fast, reliably, and predictably on real user hardware. The role is centered on engineering quality at runtime level, including startup behavior, memory pressure, throughput/latency balance, and long-session stability. You will define and evolve the core abstractions that inference features depend on, so new capabilities can be added without sacrificing performance or maintainability. This is a role for someone who enjoys low-level problem solving, clear technical ownership, and building infrastructure that other teams trust in production. Your work directly enables private, on-device AI experiences and helps set the technical foundation for QVAC's next generation of peer-to-peer AI products.

AI Inference Engineer QVAC (100% remote Worldwide)

Remote

6 link clicks.

Full Stack Engineer

1 link clicks.

Product Engineering - Team Lead

Web3 Backend jobs in London, United KingdomWintermute, Tether Operations Limited and other crypto companies

Find Backend Jobs in London, United Kingdom. Build robust blockchain APIs and infrastructure services. Browse 3+ open roles at Wintermute, Tether Operations Limited. Apply now!

Web3 Backend Jobs in London, United Kingdom

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Past and filled jobs:

AI Inference Engineer QVAC (100% remote Worldwide)

Tether Operations Limited

Hiring Backend Talent?

Job Title	Company Name	Location	Tags
AI Inference Engineer QVAC (100% remote Worldwide)	Tether Operations Limited		AIC++EngineeringBackend
Full Stack Engineer	Wintermute	📍 London, United Kingdom	Full StackBackendFrontendFull Time
Product Engineering - Team Lead	Wintermute	📍 London, United Kingdom	Engineering ManagerFrontendBackendFull Time
Past and filled jobs:
Staff Machine Learning Engineer	MoonPay	📍 London, United Kingdom	Machine LearningEngineeringBackendSenior
Staff+ Software Engineer	Plasma		SeniorBackendFull StackTypeScript
Lead Software Engineer(Java)	ARQ		SeniorBackendJavaEngineering
Full Stack Engineer, Blockchain	Fireblocks	📍 London, United Kingdom	Full StackBackendEngineeringDeFi
Data Analyst, Product	Kraken		Data AnalystPythonBackendAI