R Developer Jobs in London, UK

Senior Developer Experience Engineer at 9fin. Apply via Ashby.

Senior Developer - Real Time Investment Data Location: London (Hybrid - 3 days onsite Salary: Up to 110,000 + 25% Performance Bonus + 13.5k Partnership Bonus + Excellent Benefits About the role: I'm currently supporting a leading global investment firm in hiring a Senior Developer to join their Front Office Investment Technology team. This is a fantastic opportunity to work on a strategic, multi-year programme building a centralised Real-Time In...

We are partnering with a leading commodities and energy trading firm to hire a skilled Endur Developer. This is an exciting opportunity to contribute to the evolution and support of a critical trading platform used across front, middle, and back-office operations. You will play a key role in delivering technical solutions, enhancing platform capabilities, and ensuring the stability of Endur across the trade lifecycle. What You’ll Be Doing Delive...

<div class="content-intro"><p><strong>Who We Are:<br></strong>Galaxy is a global leader in digital assets and data center infrastructure, delivering solutions that accelerate progress in finance and artificial intelligence. We believe that blockchain and digital asset innovation will transform how value moves through the world – and we’re building the products and services to make that future a reality.<br> <br>Our institutional digital assets platform spans trading, investment banking, asset management, staking, self-custody, and tokenization technology. We also invest in and operate cutting-edge data center infrastructure to power AI and high-performance computing, addressing the growing demand for scalable energy and compute in the U.S.<br> <br>We work at the intersection of finance and technology, helping institutions, startups, and developers navigate a digitally native economy. Led by CEO and Founder Michael Novogratz, our team blends deep crypto expertise with institutional experience and a shared commitment to shaping the future of Web3 and AI.<br> <br>Galaxy is headquartered in New York City, with offices across North America, Europe, the Middle East, and Asia.<br> <br>To learn more about our businesses and products, visit www.galaxy.com.</p> <p><strong>What We Value:</strong></p> <p>We are a diverse team of free thinkers, and fast movers united to help investors and creators energize the global economy. We are looking for individuals who thrive in a culture of builders and overachievers and embrace high performance, transparent feedback, and a mission-first approach. Our culture shapes our way of working and gets us where we want to be.</p> <ul> <li><em>Seek Excellence.</em></li> <li><em>Be Selective To Be Effective.</em></li> <li><em>Be Highly Aligned, Loosely Coupled.</em></li> <li><em>Disagree Transparently.</em></li> <li><em>Encourage Independent Decision-Making.</em></li> <li><em>Build Dream Teams.</em></li> </ul></div><p><strong>Who You Are:</strong></p> <p>We’re seeking an experienced Algo / SOR Developer to join our team in London. You will have a proven track record of building and benchmarking execution algorithms from the ground up.</p> <p>Ideally, you’ve been actively engaged with the crypto markets, or have a strong curiosity about them. In this role, you will take a lead in developing greenfield algorithmic trading systems, shaping the core of our next-generation trading infrastructure.</p> <p>You’ll work closely with trading teams, stakeholders, and external partners to deliver critical initiatives that drive ou

This position can be based in Dublin or London.<br/><br/>Today, Amazon Web Services provides a highly reliable, scalable, low-cost infrastructure platform in the cloud that powers hundreds of thousands of businesses in 190 countries around the world. The AWS Cloud infrastructure is built around Regions and Availability Zones (AZs). AWS Regions provide multiple, physically separated and isolated Availability Zones which are connected with low latency, high throughput, and highly redundant networking. These Availability Zones offer AWS customers an easier and more effective way to design and operate applications and databases, making them more highly available, fault tolerant, and scalable than traditional single datacenter infrastructures or multi-datacenter infrastructures. How would you like to come be part of the team that builds out that low latency, high throughput, and highly redundant network?<br/><br/>AWS is seeking an exceptional Backbone Network Developer to help architect and scale one of the world's most sophisticated networks. As a key member of our Backbone Network Development organization, you will drive innovation in network scaling while maintaining AWS's renowned operational excellence. This role offers the unique opportunity to shape the future of global network infrastructure while solving complex challenges at unprecedented scale. You will leverage your technical expertise and commercial acumen to develop creative solutions that support Amazon's continued worldwide growth and expansion. Join us in building the future of cloud infrastructure at AWS, where your contributions will have global impact. This position sits within our Backbone Network Development organization, a team critical to Amazon's global infrastructure and connectivity strategy.<br/>AWS Infrastructure Services owns the design, planning, delivery, and operation of all AWS global infrastructure. In other words, we’re the people who keep the cloud running. We support all AWS data centers and all of the servers, storage, networking, power, and cooling equipment that ensure our customers have continual access to the innovation they rely on. We work on the most challenging problems, with thousands of variables impacting the supply chain — and we’re looking for talented people who want to help.<br/><br/>You’ll join a diverse team of software, hardware, and network engineers, supply chain specialists, security experts, operations managers, and other vital roles. You’ll collaborate with people across AWS to help us deliver the highest standards for safety and security while providing seemingly infinite capacity at the lowest possible cost for our customers. And you’ll experience an inclusive culture that welcomes bold ideas and empowers you to own them to completion. <br/><br/>Key job responsibilities<br/>Network Strategy & Development<br/> - Drive AWS's European backbone network infrastructure strategy and execution<br/> - Design and implement large-scale network architecture supporting Amazon's global operations<br/> - Develop and execute strategic network expansion plans with regular milestone tracking<br/> - Optimize network topology for maximum efficiency and cost-effectiveness<br/> - Monitor and analyze telecommunications market trends, emerging technologies, and industry developments<br/><br/>Vendor & Partnership Management<br/> - Identify and evaluate strategic suppliers for wavelengths, dark fiber, and submarine cable capacity<br/> - Lead technical vendor strategy across AWS's European network topology<br/> - Develop and maintain key commercial and technical partnerships within Europe<br/> - Manage supplier onboarding, performance metrics, and service quality standards<br/> - Coordinate with vendors and internal teams to deliver new backbone capacity<br/><br/>Financial & Project Management<br/>- Collaborate with finance partners on budget planning and allocation<br/> - Manage risk assessment, escalations, and technical constraint resolution<br/> - Balance business requirements with technical limitations and cost considerations<br/><br/>About the team<br/>Diverse Experiences<br/>AWS values diverse experiences. Even if you do not meet all of the qualifications and skills listed in the job description, we encourage candidates to apply. If your career is just starting, hasn’t followed a traditional path, or includes alternative experiences, don’t let it stop you from applying. <br/><br/>Why AWS?<br/>Amazon Web Services (AWS) is the world’s most comprehensive and broadly adopted cloud platform. We pioneered cloud computing and never stopped innovating — that’s why customers from the most successful startups to Global 500 companies trust our robust suite of products and services to power their businesses.<br/><br/>Inclusive Team Culture<br/>Here at AWS, it’s in our nature to learn and be curious. Our employee-led affinity groups foster a culture of inclusion that empower us to be proud of our differences. Ongoing events and learning experiences, including our Conversations on Race and Ethnicity (CORE) and AmazeCon conferences, inspire us to never stop embracing our uniqueness.<br/><br/>Mentorship & Career Growth<br/>We’re continuously raising our performance bar as we strive to become Earth’s Best Employer. That’s why you’ll find endless knowledge-sharing, mentorship and other career-advancing resources here to help you develop into a better-rounded professional. <br/><br/>Work/Life Balance<br/>We value work-life harmony. Achieving success at work should never come at the expense of sacrifices at home, which is why we strive for flexibility as part of our working culture. When we feel supported in the workplace and at home, there’s nothing we can’t achieve in the cloud.

&lt;p&gt;At Rockstar Games, we create world-class entertainment experiences.&amp;nbsp;&lt;/p&gt; &lt;p&gt;Become part of a team working on some of the most rewarding, large-scale creative projects to be found in any entertainment medium - all within an inclusive, highly-motivated environment where you can learn and collaborate with some of the most talented people in the industry.&lt;/p&gt; &lt;p&gt;&lt;span data-contrast=&quot;auto&quot;&gt;Rockstar is seeking an experienced Senior Developer Relations Manager to grow our Developer Relations team within Rockstar’s Creator Platform, which includes the&amp;nbsp;FiveM&amp;nbsp;and&amp;nbsp;RedM&amp;nbsp;multiplayer modification platforms as well as the&amp;nbsp;Cfx&amp;nbsp;Marketplace.&amp;nbsp;&lt;/span&gt;&lt;span data-ccp-props=&quot;{&amp;quot;335559739&amp;quot;:0}&quot;&gt;&amp;nbsp;&lt;/span&gt;&lt;/p&gt; &lt;p&gt;&lt;span data-contrast=&quot;auto&quot;&gt;In this role, you will&amp;nbsp;help&amp;nbsp;define and execute our&amp;nbsp;Developer&amp;nbsp;Relations&amp;nbsp;program&amp;nbsp;and ensure our community of creators has a strong, consistent voice within the organization.&amp;nbsp;If you have a passion for&amp;nbsp;building programs that&amp;nbsp;bridge the gap between&amp;nbsp;developer&amp;nbsp;communities&amp;nbsp;and&amp;nbsp;creator&amp;nbsp;platforms, we want to hear from you.&lt;/span&gt;&lt;span data-ccp-props=&quot;{&amp;quot;335559739&amp;quot;:0}&quot;&gt;&amp;nbsp;&lt;/span&gt;&lt;/p&gt; &lt;p&gt;This is a full-time, permanent and in-office position based in Rockstar’s unique game development studio in the heart of London.&lt;/p&gt; &lt;h4&gt;&lt;strong&gt;WHAT WE DO&lt;/strong&gt;&lt;/h4&gt; &lt;ul&gt; &lt;li&gt;&lt;span data-contrast=&quot;auto&quot;&gt;The&amp;nbsp;Rockstar&amp;nbsp;Games&amp;nbsp;Creator Platform Team&amp;nbsp;delivers&amp;nbsp;a technology platform that enables players to experience&amp;nbsp;community-created content on fully customized dedicated servers where creators can develop their own game modes and other modifications in a variety of scripting languages.&lt;/span&gt;&lt;span data-ccp-props=&quot;{&amp;quot;201341983&amp;quot;:0,&amp;quot;335559739&amp;quot;:0,&amp;quot;335559740&amp;quot;:276}&quot;&gt;&amp;nbsp;&lt;/span&gt;&lt;/li&gt; &lt;li&gt;&lt;span data-contrast=&quot;auto&quot;&gt;We provide a curated digital storefront, the&amp;nbsp;Cfx&amp;nbsp;Marketplace, where talented&amp;nbsp;GTAV and RDR2&amp;nbsp;creators can share and sell&amp;nbsp;custom&amp;nbsp;scripts,&amp;nbsp;assets, and more.&lt;/span&gt;&lt;span data-ccp-props=&quot;{&amp;quot;201341983&amp;quot;:0,&amp;quot;335559739&amp;quot;:0,&amp;quot;335559740&amp;quot;:276}&quot;&gt;&amp;nbsp;&lt;/span&gt;&lt;/li&gt; &lt;li&gt;&lt;span data-contrast=&quot;auto&quot;&gt;We work closely with our worldwide community of players, creators, and server operators to&amp;nbsp;grow&amp;nbsp;our&amp;nbsp;platform, and&amp;nbsp;act&amp;nbsp;as a point of contact between the community and our

&lt;p&gt;At Rockstar Games, we create world-class entertainment experiences.&amp;nbsp;&lt;/p&gt; &lt;p&gt;Become part of a team working on some of the most rewarding, large-scale creative projects to be found in any entertainment medium - all within an inclusive, highly-motivated environment where you can learn and collaborate with some of the most talented people in the industry.&lt;/p&gt; &lt;p&gt;&lt;span data-contrast=&quot;auto&quot;&gt;Rockstar is seeking a talented Senior Developer Advocate to support our Creator Platform team, which includes the FiveM and RedM multiplayer modification platforms.&amp;nbsp;&lt;/span&gt;&lt;span data-ccp-props=&quot;{&amp;quot;335559739&amp;quot;:0}&quot;&gt;&amp;nbsp;&lt;/span&gt;&lt;/p&gt; &lt;p&gt;&lt;span data-contrast=&quot;auto&quot;&gt;In this role, you will&amp;nbsp;focus on improving the developer&amp;nbsp;experience for our creators, including&amp;nbsp;translating&amp;nbsp;complex technical concepts into clear, accessible guides, tutorials, and API references&amp;nbsp;to&amp;nbsp;empower our worldwide community of creators and server owners to get the most out of&amp;nbsp;our Creator Platforms.&lt;/span&gt;&lt;/p&gt; &lt;p&gt;This is a full-time, permanent and in-office position based in Rockstar’s unique game development studio in the heart of London.&amp;nbsp;&lt;/p&gt; &lt;h4&gt;&lt;strong&gt;WHAT WE DO&lt;/strong&gt;&lt;/h4&gt; &lt;ul&gt; &lt;li&gt;&lt;span data-contrast=&quot;auto&quot;&gt;The Rockstar Games Creator Platform Team&amp;nbsp;deliver&amp;nbsp;a technology platform that enables players to experience community created content on fully customized dedicated servers where creators can develop their own game modes and other modifications in a variety of scripting languages.&lt;/span&gt;&lt;span data-ccp-props=&quot;{&amp;quot;201341983&amp;quot;:0,&amp;quot;335559739&amp;quot;:0,&amp;quot;335559740&amp;quot;:276}&quot;&gt;&amp;nbsp;&lt;/span&gt;&lt;/li&gt; &lt;li&gt;&lt;span data-contrast=&quot;none&quot;&gt;We provide a curated digital storefront, the&amp;nbsp;Cfx&amp;nbsp;Marketplace, where talented&amp;nbsp;&lt;/span&gt;&lt;span data-contrast=&quot;none&quot;&gt;GTAV and RDR2&amp;nbsp;&lt;/span&gt;&lt;span data-contrast=&quot;none&quot;&gt;creators can share and sell&lt;/span&gt;&lt;span data-contrast=&quot;none&quot;&gt;&amp;nbsp;custom&amp;nbsp;&lt;/span&gt;&lt;span data-contrast=&quot;none&quot;&gt;scripts,&amp;nbsp;&lt;/span&gt;&lt;span data-contrast=&quot;none&quot;&gt;assets&lt;/span&gt;&lt;span data-contrast=&quot;none&quot;&gt;, and more.&lt;/span&gt;&lt;span data-ccp-props=&quot;{&amp;quot;201341983&amp;quot;:0,&amp;quot;335559739&amp;quot;:0,&amp;quot;335559740&amp;quot;:276}&quot;&gt;&amp;nbsp;&lt;/span&gt;&lt;/li&gt; &lt;li&gt;&lt;span data-contrast=&quot;auto&quot;&gt;We produce developer documentation, tutorials, and learning resources that help&amp;nbsp;our creator community&amp;nbsp;understand our platform capabilities, APIs, and best practices.&lt;/span&gt;&lt;/li&gt

Discover your future at Citi Working at Citi is far more than just a job. A career with us means joining a team of more than 230,000 dedicated people from around the globe. At Citi, you'll have the opportunity to grow your career, give back to your community and make a real impact. Job Overview About Citi As the world's most global bank, Citi gives you the tools to be a trailblazer. We're not just building technology; we're building the future o...

Discover your future at Citi Working at Citi is far more than just a job. A career with us means joining a team of more than 230,000 dedicated people from around the globe. At Citi, you'll have the opportunity to grow your career, give back to your community and make a real impact. Job Overview About Citi As the world's most global bank, Citi gives you the tools to be a trailblazer. We're not just building technology; we're building the future o...

We are partnering with a leading commodities and energy trading firm to hire a skilled Endur Developer. This is an exciting opportunity to contribute to the evolution and support of a critical trading platform used across front, middle, and back-office operations. You will play a key role in delivering technical solutions, enhancing platform capabilities, and ensuring the stability of Endur across the trade lifecycle. What You’ll Be Doing Delive...

My client is a leading systematic trading firm that operates in all liquid asset across most major markets. They are looking for a highly experienced developer to join one of their core teams responsible for building and enhancing key components that directly affect their algorithmic trading and data management systems. This role is an excellent opportunity to work directly with Traders &amp; Researchers on bespoke tooling and their most immedia...

Discover your future at Citi Working at Citi is far more than just a job. A career with us means joining a team of more than 230,000 dedicated people from around the globe. At Citi, you'll have the opportunity to grow your career, give back to your community and make a real impact. Job Overview The Analytical Calculation Engine (ACE) Development Team is a group within Citi Financial Risk Technology, responsible for developing and implementing th...

Discover your future at Citi Working at Citi is far more than just a job. A career with us means joining a team of more than 230,000 dedicated people from around the globe. At Citi, you'll have the opportunity to grow your career, give back to your community and make a real impact. Job Overview About Citi As the world's most global bank, Citi gives you the tools to be a trailblazer. We're not just building technology; we're building the future o...

&lt;p&gt;Qube Research &amp;amp; Technologies (QRT) is a global quantitative and systematic investment manager, operating in all liquid asset classes across the world. We are a technology- and data-driven group implementing a scientific approach to investing. Combining data, research, technology, and trading expertise has shaped our collaborative mindset, which enables us to solve the most complex challenges. QRT’s culture of innovation continuously drives our ambition to deliver high-quality returns for our investors.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt; &lt;p&gt;You will join the Core Trading Platform team, which is responsible for the design and operation of QRT’s global electronic trading infrastructure. This team builds and maintains the ultra-low latency systems that underpin real-time trading, managing performance-critical workflows across global markets. You will work closely with developers, traders, and operations to optimise system behaviour, reduce latency, and ensure platform reliability at scale.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt; &lt;p&gt;&lt;strong&gt;Your future role within QRT&lt;/strong&gt;&lt;/p&gt; &lt;ul&gt; &lt;li&gt;Design and implement low-latency trading systems on Linux, focused on throughput, reliability, and determinism&lt;/li&gt; &lt;li&gt;Engineer scalable, high-performance distributed systems that support global real-time trading workflows&lt;/li&gt; &lt;li&gt;Analyse system behaviour using low-level tools such as packet captures, core dumps, and runtime profilers&lt;/li&gt; &lt;li&gt;Apply deep expertise in TCP, UDP, and multicast to understanding trade-offs in short-haul vs long-haul networks&lt;/li&gt; &lt;li&gt;Continuously profile, benchmark, and optimise code to reduce latency and increase throughput&lt;/li&gt; &lt;li&gt;Engage across the full software lifecycle: from architecture to debugging in live trading environments&lt;/li&gt; &lt;/ul&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt; &lt;p&gt;&lt;strong&gt;Your present skillset&lt;/strong&gt;&lt;/p&gt; &lt;ul&gt; &lt;li&gt;5+ years of professional C++/C development experience on Linux, including modern C++ and multithreading&lt;/li&gt; &lt;li&gt;Strong expertise in TCP, UDP, multicast, and performance trade-offs in low-latency networks&lt;/li&gt; &lt;li&gt;Experience building and operating high-throughput distributed systems in production&lt;/li&gt; &lt;li&gt;Familiarity with scalable I/O models (e.g., epoll, io_uring), lock-free structures, and concurrent programming&lt;/li&gt; &lt;li&gt;Deep attention to detail with a rigorous approach to performance troubleshooting and optimisation&lt;/li&gt; &lt;li&gt;Proficiency in system-level tools (e.g., gdb, perf, tcpdump, valgrind, wireshark)&lt;/li&gt; &lt;li&gt;Comfortable working autonomously and taking ownership from problem to solution&lt;/li&gt; &lt;li&gt;Scripting experience (e.g., Python, Bash) and exposure to CI/CD or observability tooling is a plus&lt;/li&gt; &lt;li&gt;Prior exposure to electronic trading or

&lt;div class=&quot;content-intro&quot;&gt;&lt;p&gt;At Algolia, we’re proud to be a pioneer and market leader in AI Search, empowering 17,000+ businesses to deliver blazing-fast, predictive search and browse experiences at internet scale. Every week, we power over 30 billion search requests — four times more than Microsoft Bing, Yahoo, Baidu, Yandex, and DuckDuckGo combined.&lt;/p&gt; &lt;p&gt;In 2021, we raised $150 million in Series D funding, quadrupling our valuation to $2.25 billion. This strong foundation enables us to keep investing in our market-leading platform and serving incredible customers like Under Armour, PetSmart, Stripe, Gymshark, and Walgreens.&lt;/p&gt;&lt;/div&gt;&lt;p&gt;At Algolia, we are passionate about helping developers and product teams connect their users with what matters most in milliseconds!&lt;/p&gt; &lt;p&gt;Algolia was built to help users deliver an intuitive search-as-you-type experience on their websites and mobile apps. We provide a search API used by thousands of customers in more than 100 countries, handling billions of search queries monthly.&lt;/p&gt; &lt;p&gt;The Junior Developer Support Engineer is a critical role at Algolia. We’re on the front-lines and are often the first team customers contact when they need help with our products or services. We&#39;re looking for a Junior Developer Support Engineer to assist our technical users with implementing Algolia in a variety of web and mobile development technical stacks.&lt;/p&gt; &lt;p&gt;This could mean helping a developer trying to build the next big thing in their garage, or Fortune 500 companies focused on providing a world-class experience to their millions of users.&lt;/p&gt; &lt;p&gt;As a Junior Developer Support Engineer, you will partner with the customer success, product, and engineering teams to find the best solutions for our customers.. We have a hands-on culture, and expect you to roll up your sleeves and get to work solving difficult problems that stand in the way of our customers’ success.&lt;/p&gt; &lt;p&gt;YOUR ROLE WILL CONSIST OF:&lt;/p&gt; &lt;ul&gt; &lt;li&gt;Handling technical requests via web and email support channels.&lt;/li&gt; &lt;li&gt;Conducting professional and empathetic conversations with customers to gather information, troubleshoot, and resolve their technical obstacles.&lt;/li&gt; &lt;li&gt;Submitting bug reports to the Engineering team for problems needing attention.&lt;/li&gt; &lt;li&gt;Partnering with Product Teams and Engineering to develop subject matter expertise and serve as a product expert to the rest of the support team.&lt;/li&gt; &lt;li&gt;Contributing to internal and external knowledge bases.&lt;/li&gt; &lt;li&gt;Participating in internal projects to improve processes and tools.&lt;/li&gt; &lt;/ul&gt; &lt;p&gt;REQUIREMENTS:&lt;/p&gt; &lt;ul&gt; &lt;li&gt;Strong desire to help people solve problems with the ability to explain complex technical&amp;nbsp; concepts to a broad audience&lt;/li&gt; &lt;li&gt;Exper

Senior Developer Experience Security Engineer at Motorway. Apply via Ashby.

Discover your future at Citi Working at Citi is far more than just a job. A career with us means joining a team of more than 230,000 dedicated people from around the globe. At Citi, you'll have the opportunity to grow your career, give back to your community and make a real impact. Job Overview About Citi As the world's most global bank, Citi gives you the tools to be a trailblazer. We're not just building technology; we're building the future o...

Senior Salesforce Developer Location: London (Hybrid Working) Salary: 75,000 - 85,000 + 20% Bonus Employment Type: Full-time, Permanent Dynamic and growing property business based in London, focused on delivering innovative real estate solutions across residential and commercial markets. As part of our continued digital transformation, we are investing heavily in our Salesforce platform to enhance customer experience, streamline operations, and ...