Functional Software Engineer | London

About the Role Jane Street is seeking talented Software Engineers who are eager to contribute to the design and development of the systems and tools that drive our operations. Our Software Engineers are integrated throughout the company, tackling complex challenges that span from trading desks to accounting, as well as creating essential infrastructure, including network monitoring solutions and risk models. We are strong advocates of functional programming, primarily utilizing OCaml, a statically-typed functional programming language. Recently, Python has emerged as a crucial component in our research and trading initiatives, serving as the primary language for data analysis, visualization, and machine learning. In addition to our internal practices, we value the significance of open-source software. We actively incorporate it into our daily operations and have released over a million lines of our code as open source. We are continually looking for ways to enhance open-source projects and provide ongoing support for tools like Mercurial, the OCaml compiler, and the OPAM package manager. We welcome passionate engineers with experience in any programming language; most of our team members started with minimal practical knowledge of OCaml. To learn more about our interview process and meet some of our newest hires, feel free to explore.

About the PositionAt Jane Street, we are constantly on the lookout for talented software engineers across all our offices. Technology lies at the heart of our operations, and our engineers play a crucial role in every facet of our business.We embrace functional programming, utilizing OCaml—a statically typed functional programming language—as our primary tool. Recently, Python has also become integral to our research and trading processes, serving as the preferred language for data analysis, visualization, and machine learning.We are strong advocates for open-source software, actively employing it in our daily tasks and contributing over a million lines of our own code to the open-source community.About YouExceptional programming skillsA profound passion for technology. While there is no specific checklist, we utilize software to tackle diverse challenges, so we welcome experience spanning machine learning, systems administration, and programming language design.Excellent interpersonal skills. Software engineering at Jane Street is highly collaborative, and we seek individuals who thrive in small, close-knit teams.No prior experience in functional programming, OCaml, Python, or finance is required; we are eager to hire talented engineers and provide the necessary training.Fluency in English is mandatory.To learn more about our software engineering interview process, visit our interview prep page.

About the Role demo.levels.fyi is hiring a Software Engineer in London. This role works closely with teammates to build and improve products that impact users directly. The team values collaboration and encourages new ideas that move the product forward. What to Expect Contribute to product development and user experience improvements Work with others to solve technical challenges Apply modern software and design practices About demo.levels.fyi With roots going back to the 1500s, demo.levels.fyi blends a long history with ongoing innovation in technology. The company continues to evolve, focusing on new approaches in software and design.

Our Journey Welcome to Zopa! Founded in 2005, Zopa pioneered the peer-to-peer lending landscape and in 2020, we proudly launched Zopa Bank. We’re on a mission to transform the banking experience by listening closely to our customers and addressing their concerns with innovative solutions. Our vision centers on placing individuals at the heart of banking, empowering them to aim high and advance the financial world. Discover more about our exciting services at Zopa.com! Our accomplishments are a testament to the incredible talent within our team. We’re not just collecting industry accolades; we’ve also been recognized as one of the top three Most Loved Workplaces in the UK. If you are enthusiastic about tackling unconventional challenges, eager to think outside the box, and driven to create a significant impact, Zopa is the place for you. Join us and make a difference! Want to see our culture in action? Follow us on Instagram @zopalife.The Engineering OpportunityAs a Software Engineer at Zopa, you will do more than just code; you will engage in solving meaningful financial challenges for millions of customers. You will work on distributed systems that process thousands of transactions daily, develop robust services that manage financial assets, and design user experiences that simplify traditionally complex financial products.

Join our dynamic team at getscope as a Software Engineer, where innovation meets excellence. As a key member of our development team, you will work on cutting-edge projects, contribute to all phases of the software development lifecycle, and help us deliver high-quality software solutions. This role offers an exciting opportunity for growth and collaboration in a fast-paced environment.

Join our innovative team at Faculty as a Software Engineer. In this role, you will be responsible for developing scalable software solutions that meet the needs of our clients. You will collaborate with cross-functional teams, utilizing the latest technologies to deliver high-quality products.

Join Our Team! At demo.levels.fyi, we are looking for a passionate Software Engineer to contribute to innovative projects in the tech industry. Our team thrives on creativity and collaboration, fostering an environment where ideas bloom. You will be working with cutting-edge technologies and play a crucial role in developing solutions that redefine the user experience.

Senior Software EngineerBecome a key player in our mission to revolutionize the shopping and dining experience, where innovation, impact, and growth are at the forefront of everything we pursue. Our Engineering teams tackle intricate technical challenges across a global, three-sided marketplace, constructing and scaling systems that cater to millions of customers, riders, and partners daily.From real-time logistics to robust infrastructure and marketplace optimization, we design, build, and operate technology that fuels Deliveroo’s expansive growth.We seek a Senior Software Engineer to join our London (Hybrid - 3 days from the office) team. In this pivotal role, you will enhance code structure and architecture while leading project planning to maximize efficiency and reliability across our production systems.Familiarize yourself with our Engineering team — discover what motivates us, our work culture, and what you can anticipate.Your ResponsibilitiesHere’s what your day-to-day might encompass:Pursue Technical Excellence: Refine code structure and architecture within your team’s domain, conducting impactful code reviews to ensure quality and scalability.Steer Project Planning: Anticipate dependencies and risks, collaborating closely with Product and Design to ensure seamless delivery of complex features.Enhance Operations: Streamline the maintenance and operation of production systems, fostering visibility, health, and operational readiness.Collaborate & Influence: Cultivate relationships across engineering teams to uncover collaboration opportunities and influence the broader technical roadmap.Mentor & Recruit: Facilitate the personal development of your colleagues through technical mentorship and actively participate in engineering interviews to expand our team.Desired QualificationsOur ideal candidate will bring robust expertise in several of these areas and a willingness to grow in others:Solid Engineering Principles: A strong commitment to crafting readable, well-designed, and thoroughly tested software.Backend Proficiency: Extensive experience in developing web-based applications (we utilize Go, Ruby/Rails, Python, Scala, and Rust).Data Proficiency: Familiarity with data handling and optimization techniques.

We are seeking an experienced Senior Software Engineer to join our innovative team at AECOM in London. In this role, you will be responsible for designing, developing, and implementing software solutions that meet client needs. You will collaborate with cross-functional teams to deliver high-quality products and improve our software development processes.

About xAIAt xAI, we are dedicated to developing cutting-edge AI systems that enhance humanity's understanding of the universe and support our quest for knowledge. Our team is compact yet highly driven, committed to engineering excellence. We seek individuals who relish challenges and thrive on curiosity. Our flat organizational structure empowers all employees to take initiative and contribute meaningfully to our mission. We value strong work ethics and prioritization skills, and we expect our team members to communicate effectively and share knowledge concisely with one another. About the TeamAs a member of our team, you will engage with the full xAI technology stack, encompassing model development to production infrastructure. This role is based in London, UK, and we will align you with a suitable team during the offer stage.About the RoleWe understand that every candidate has a unique journey. Whether you’ve engineered embedded systems for spacecraft or developed large-scale distributed infrastructure, we believe that engineers who excel in one challenging domain can thrive in others. At xAI, our primary focus is on training advanced AI models and delivering products built on them. If you possess a proven track record of remarkable achievements—be it resolving critical issues under tight deadlines or successfully reviving a struggling project—we encourage you to apply, even if your background doesn’t align perfectly with machine learning or software development. The “statement of exceptional work” section in your application is paramount; please take the time to be concise, specific, and concrete.Interview ProcessApplication review.15-minute technical call with the team.Technical interviews.Role alignment discussion.

About Mistral AIAt Mistral AI, we harness the transformative power of artificial intelligence to simplify daily tasks, save precious time, and enhance learning and creativity. Our innovative technology is crafted to seamlessly integrate into the fabric of everyday work life.We are on a mission to democratize AI through high-performance, optimized, and cutting-edge open-source models and solutions. Our robust AI platform is tailored to meet the diverse needs of enterprises, whether on-premises or in the cloud. Our flagship offerings include Le Chat, your AI assistant for both life and work.We pride ourselves on being a dynamic, collaborative team deeply passionate about AI and its potential to reshape society. Our diverse workforce thrives in competitive environments and is dedicated to fostering innovation. With teams distributed across France, the USA, the UK, Germany, and Singapore, we embody creativity, humility, and a strong team spirit.Join us on this exciting journey as we shape the future of AI, making a meaningful impact together. Discover more about our vibrant culture at https://mistral.ai/careers.Role OverviewWe are on the lookout for passionate and talented Software Engineers to join our team. As a Backend Engineer, you will play a pivotal role in developing the core systems that power our key products: AI Studio, Le Chat, and Mistral Code. You will shape how users and developers interact with our AI platform at scale. Your focus will be on building reliable, high-performance backend systems and APIs that support millions of users and developers. Your contributions will directly enhance the user and developer experience, making it more engaging, efficient, and intuitive. We welcome engineers at all levels, from fresh graduates to seasoned professionals who are eager to learn, collaborate, and deliver impactful solutions.Key ResponsibilitiesBased on your expertise, you will engage in crucial components of our technology, including:Backend Development- Design, develop, and maintain scalable and robust backend features and APIs using modern frameworks.- Ensure high performance and reliability across our distributed systems.- Contribute to systems that support authentication, billing, AI tooling, and observability.

Join Aircall, a leading unicorn in the customer communications sector, revolutionizing the way businesses connect with their customers. Our AI-powered platform, trusted by over 22,000 companies globally, integrates voice, SMS, WhatsApp, and AI into a single cohesive workspace, enhancing revenue generation, expediting issue resolution, and empowering customer-facing teams.At Aircall, we believe in working smarter, not harder. Our AI Voice Agent automates routine calls, AI Assist simplifies post-call tasks, and AI Assist Pro offers real-time support, enabling teams to perform at their best. This innovation leads to increased revenue, quicker resolutions, and scalable teams.Headquartered in Paris, with a robust presence in North America centered in Seattle, Aircall has teams across various cities including Madrid, London, Berlin, San Francisco, New York City, Sydney, and Mexico City. We have crafted a beloved product and a rapidly growing business, supported by top-tier investors and driven by swift AI advancements across our offerings.At Aircall, you will become part of a dynamic and ambitious organization, where product excellence and execution are paramount. We prioritize swift decision-making, visible impact, and genuine growth.Our Work Culture: We are dedicated to our customers, rely on data-driven insights, and are focused on delivering impactful results. We value responsibility, continuous learning, and thoughtful speed. If you thrive in a collaborative, fast-paced environment where trust and impact are essential, you'll fit right in.We are seeking a motivated and passionate Senior Software Engineer to join our expanding engineering team and contribute to our innovative projects.In this role, you will be responsible for the design, development, deployment, and operation of critical features that enhance customer satisfaction. You will focus on operational excellence, metrics, observability, and best practices while mentoring your peers within the engineering team.With a commitment to quality, excellence, and agility, you will help elevate our delivery processes. Utilizing a NodeJS and Typescript back-end stack hosted on AWS, you will ensure that our solutions meet the highest standards.

Join Our Team!Are you an innovative Senior Software Engineer looking to make a significant impact? At Perk, we are redefining the landscape of travel and spend management with our intelligent platform. Our mission is to eliminate the tedious manual tasks that hinder productivity, allowing professionals to focus on what truly matters.Since our establishment in 2015, we've grown to serve over 10,000 companies globally, including renowned names like Wise, On Running, and Breitling. Our cutting-edge tools streamline everything from travel bookings to expense management, addressing a staggering $1.7 trillion problem of lost productivity.With a vibrant workforce of over 1,800 talented individuals across 12 offices, we are committed to fostering innovation and enhancing workplace culture. We believe in the power of curiosity, purpose, and teamwork, and we want you to be part of our journey to transform how businesses operate.

At Ripple, we are pioneering a future where value transfers seamlessly, akin to the flow of information. Our vision is ambitious, and we are already transforming the landscape. With our innovative crypto solutions tailored for financial institutions, businesses, governments, and developers, we are enhancing the global financial ecosystem, fostering economic equity, and creating opportunities for individuals worldwide. Join a team where you can engage in meaningful work while honing your skills in a supportive and collaborative environment.If you are eager to witness the tangible impact of your contributions and explore remarkable career advancement possibilities, we invite you to be part of our journey to create real-world value.At Ripple, we’re building a world where value moves like information does today. It’s big, it’s bold, and we’re already doing it. Through our crypto solutions for financial institutions, businesses, governments and developers, we are improving the global financial system and creating greater economic fairness and opportunity for more people, in more places around the world. And we get to do the best work of our career and grow our skills surrounded by colleagues who have our backs.If you’re ready to see your impact and unlock incredible career growth opportunities, join us, and build real world value.

alten seeks a Backend Software Engineer for its Space Department in London. This role centers on developing software solutions that contribute to important projects and advance the team's technology. Role overview The Backend Software Engineer will work on building and maintaining systems that support the department's ongoing initiatives. The position involves collaborating with colleagues to deliver reliable and effective backend solutions. Location This position is based in London.

About Us Welcome to Zopa! Since our inception in 2005, we have pioneered the peer-to-peer lending landscape, and in 2020, we proudly launched Zopa Bank. Our mission is to revolutionize the banking experience by actively listening to our customers and addressing their financial concerns. We are committed to creating a banking ecosystem that prioritizes our customers’ needs, enabling them to reach their financial aspirations. Discover more about our innovative services at Zopa.com!Our accolades speak volumes; we not only receive industry awards but have also been recognized as one of the top three Most Loved Workplaces in the UK.If you are passionate about tackling unconventional challenges, thinking outside the box, and making a significant impact in the financial space, Zopa is the place for you. Join us and be part of something remarkable! Follow our journey on Instagram @zopalife.Your Engineering ChallengeAs a Senior Software Engineer, you won't just be writing code; you'll be tackling real financial challenges faced by millions. You will design and implement distributed systems that handle thousands of transactions each day, develop robust services to manage financial data, and simplify complex financial products to enhance user experience.

Join Our Team at AronditeArondite is a leading defence technology firm dedicated to creating the essential software and AI technologies that will shape the autonomous future. Our mission is to transform the interaction between organizations and autonomous systems, enhancing the way they interpret and utilize data generated by sensors and robots. We are fueled by a commitment to uphold democratic values and a belief that a select group of talented engineers can effect significant change. With substantial funding and a long-term vision, we are poised for remarkable growth.Your Path with UsAs a Software Engineer at Arondite, you will become part of a dynamic team at a crucial stage in our journey. We pride ourselves on being a collective of exceptional engineers who thrive on engaging with challenging, impactful projects and consistently achieve extraordinary results. You will work alongside other brilliant professionals to tackle some of the most pressing and complex challenges facing the world today.Autonomy and OwnershipFrom your very first day, you will have significant ownership and autonomy in your role. At Arondite, there is no rigid corporate hierarchy. You will directly influence the design and functionality of our product offerings, and we empower our team members with high levels of autonomy. Your ambition will define your path.If you resonate with our mission and wish to be part of a remarkable team, we would love to hear from you!

At Smarkets, we are constantly seeking exceptional engineers who are passionate about the challenges we face. If you are excited to contribute to innovative solutions and have relevant skills and experience, we invite you to apply. We eagerly await your application!We are recruiting for various levels, including mid and senior positions.About UsSmarkets: Pioneering the Future of BettingSmarkets operates one of the globe's most advanced prediction markets, processing over £29 billion in transactions since our inception in 2010, with a community of over 200,000 traders worldwide. As a technology-driven company, we are transforming the betting landscape across sports and political markets by offering competitive prices and equitable odds.Our technology stack is meticulously designed for scalability, reliability, and speed, utilizing Linux, Kafka, Postgres, Kubernetes, alongside Python 3, C++17, and React to power our platform. We build infrastructure that institutions can rely on while making trading accessible for everyone. Our resilience is demonstrated by thriving through various market cycles and industry transformations.The core of our success lies in our team. We cultivate a high-performance environment that enables exceptional talent to excel, merging profound business acumen with a commercial outlook to foster strategic growth.If you are ready to influence the future of prediction markets through innovative technology and a customer-centric approach, Smarkets is your ideal workplace.The PositionAs a Mid-Level Software Engineer in our Engineering organization, you will be instrumental in designing, developing, and maintaining the services that underpin Smarkets' business operations products. You will collaborate closely with engineering managers, technical leaders, and product managers to steer complex technical initiatives aligned with the Smarkets product roadmap.We are searching for skilled and enthusiastic engineers like you for a thrilling opportunity to create a cohesive and high-performing system that not only optimizes our services but also propels Smarkets to unparalleled levels of success.We prioritize using the most effective tools for each task. Our tech stack includes Rust for high-performance operations and Python for other functionalities. Our Kafka pub/sub message queue is central to our system, ensuring high availability, low latency, and message persistence. We provide gRPC and HTTP APIs for diverse metadata, while PostgreSQL and ElasticSearch are our preferred databases.Key Responsibilities:Design, implement, and maintain complex systems and applications that support Smarkets' operations.Work collaboratively with cross-functional teams to define project goals and deliverables.Participate in code reviews, architecture discussions, and technical planning.Continuously improve code quality, software robustness, and performance.

Join Faculty as a Software Engineer and become an integral part of our innovative team. You will be responsible for designing, developing, and maintaining software solutions that drive our projects forward. This role offers an exciting opportunity to work on cutting-edge technologies in a collaborative environment.