Lead Staff Software Engineer at The Trade Desk | London

The Trade Desk is a leading global technology firm dedicated to fostering a better, more transparent internet through principled and intelligent advertising solutions. Our platform processes over 1 trillion queries daily, operating at an unparalleled scale. Moreover, we have cultivated a robust and valuable organizational culture centered on trust, ownership…

Join Ki Insurance, a pioneer in the insurance industry, as we redefine a 335-year-old market with cutting-edge technology. Our innovative platform, developed in collaboration with Google and UCL, leverages algorithms and machine learning to deliver lightning-fast quotes to insurance brokers, transforming the industry standard.As the largest global algorithmic insurance carrier and the fastest-growing syndicate in the Lloyd's of London market, Ki Insurance has achieved extraordinary milestones, including generating $100 million in profit within just three years.Our diverse teams thrive in an agile, cross-functional environment, where collaboration and creativity lead to exceptional customer experiences. We are on the lookout for brilliant minds to join us on our mission to challenge conventions and explore new possibilities.As a Staff Software Engineer, you will play a pivotal role in our engineering team, providing technical leadership to both delivery squads and the broader engineering organization. You will champion engineering excellence and uphold high standards of quality, fostering a culture of continuous improvement. Your hands-on approach will enable you to design and deliver impactful software solutions while guiding your colleagues to achieve collective goals.Are you ready to make your mark? Develop robust and scalable software for critical web-based applications.Design, implement, test, document, and maintain APIs and integrations.Create new features within our core Kotlin-based services, collaborating with multi-disciplinary teams.Ensure quality control through techniques such as automated testing, code review, and pair programming.Work closely with the Product team to translate user requirements into effective technical solutions.Document technical designs and analyses thoroughly.Evaluate existing system architecture, identifying areas for enhancement and growth.Prototype and explore innovative ideas and technologies swiftly.Promote a culture of continuous improvement, leading by example and positively influencing our practices.

About Swap Swap builds the infrastructure for modern agentic commerce. The platform connects backend operations with a new kind of storefront, using AI to help brands manage and grow their business globally. Swap’s platform brings together cross-border operations, tax management, returns, demand forecasting, and a storefront powered by agentic technology. Merchants get real-time data, transparency, and tools to act quickly and decisively. The company values clarity, creativity, and shared ownership as it rethinks how global commerce works. Role Overview: Staff Software Engineer in Test – QA Platform Lead Swap is hiring a Staff Software Engineer in Test to lead the development of its internal QA Platform. This role focuses on building the tools and infrastructure that help engineering teams ship reliable software, faster. The QA Platform Lead will design, build, and maintain the internal platform, including frameworks, automation pipelines, and AI-assisted workflows, that Swap engineers rely on every day. The impact of this work will be measured by how widely the platform is adopted, the developer experience, and the speed at which teams can deliver quality software. Collaboration is key. The role works closely with the current SDET, who created the existing end-to-end testing framework. Together, you’ll expand on this foundation and shape a broader platform vision. The QA Platform Lead will set strategy, manage the roadmap, and make decisions about priorities and architecture. Main Responsibilities QA Platform Strategy and Roadmap Define the vision, strategy, and roadmap for the QA Platform, setting priorities that maximize impact. Make architectural and tooling decisions that influence quality practices across Swap’s engineering teams. Track adoption, usage, and developer satisfaction to ensure the platform is used and valued, not just built. Develop Reusable Quality Tools and Infrastructure Design and implement reusable tools, frameworks, and self-service quality infrastructure to help engineering teams deliver with confidence and less friction. Location This role is based in London.

At Databricks, we're committed to empowering data teams to tackle some of the world's most challenging issues, including security threat detection and cancer drug development. Our mission is to create and manage the premier data and AI infrastructure platform so our customers can dedicate their efforts to the high-value challenges crucial to their missions. Our engineering teams develop cutting-edge products that meet significant real-world needs. We operate one of the largest-scale software platforms, comprising millions of virtual machines that generate terabytes of logs and process exabytes of data daily. Given our scale, we frequently encounter hardware, network, and operating system faults, and our software must effectively shield our customers from these challenges. The Delta DML team is responsible for the core write-path operations for Delta Lake, the open-source storage layer underlying the Databricks Lakehouse. Our goal is to deliver industry-leading performance and a seamless user experience at massive scale, with most data written in Databricks passing through our platform. We innovate in performance through features like Low Shuffle Merge and Deletion Vectors, and actively contribute to open-source initiatives that unify Delta and Iceberg formats. We are on the lookout for a highly skilled and experienced Senior Staff Software Engineer to join our backend team. In this pivotal role, you will design, develop, and maintain robust backend systems that power Databricks workspaces. You will work on building the next-generation platform for serving workspace assets, ensuring high queries per second (QPS), low latency, reliability, and performance while proactively addressing future growth challenges. As a senior member of the team, your responsibilities will also include providing technical leadership, mentorship, and guidance to junior engineers, thereby enhancing the overall coding practices and system designs of the team.

Join Our Team as a Staff Software EngineerAt Deliveroo, we are dedicated to revolutionizing the way people shop and dine. Our commitment to impact, innovation, and growth is at the core of everything we do. Our engineering teams are tasked with addressing intricate technical challenges within a global, three-sided marketplace, developing 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 the technology that fuels Deliveroo's expansive growth.We are seeking a Staff Software Engineer to become a key member of our London, UK - Hybrid (3 days in the office) team. In this pivotal role, you will help us craft technical solutions for essential business challenges and steer the technical direction for complex, high-scale systems.Discover our Engineering team — learn about our motivations, work culture, and what you can expect when you join us.

Join unlikelyAI as a Staff Software Engineer and be at the forefront of developing cutting-edge artificial intelligence solutions. In this pivotal role, you will collaborate with a talented team to design, implement, and optimize software systems that push the boundaries of technology.As a key member of our engineering team, you'll have the opportunity to influence the architecture of our products and mentor junior engineers. We are looking for innovative thinkers who thrive in a fast-paced environment and are passionate about building scalable and efficient software.

Join our dynamic team as a Staff Software Engineer at CyberArk, where you will be instrumental in developing cutting-edge security solutions. You will collaborate with a talented group of engineers to design, implement, and maintain software systems that protect against evolving cyber threats. Your expertise will contribute to innovative projects that shape the future of enterprise security.

Join our innovative team at antithesis as a Senior/Staff Engineer specializing in Bombadil. In this pivotal role, you will lead engineering projects, collaborate with cross-functional teams, and drive the development of cutting-edge solutions. Your expertise will be crucial in enhancing system performance and ensuring the seamless integration of new technologies.

Tessl is an innovative Series A startup headquartered in London, founded by the visionary Guy Podjarny. With over $100M raised from esteemed investors such as Index Ventures, Accel, GV, and Boldstart, we have been recognized among the top players in the industry, ranking #2 in Sifted EU’s B2B SaaS Rising 100 and #20 in Sifted's AI 100 this year.At Tessl, we are on a mission to redefine software development through the power of AI. Our AI Native Developers are pioneering a new approach, defining features, architecture, and workflows through specifications rather than code, effectively guiding the work of AI agents. We are at the forefront of creating a groundbreaking platform that embodies this transformative vision, leading a developer movement and ecosystem.Joining Tessl means becoming an integral part of an early-stage team where you have the chance to influence the future of software creation and maintenance.

Join Plaid as a Staff Software Engineer and be a vital part of our team in London. We are looking for innovative engineers who are passionate about building the infrastructure that powers the future of fintech. You will work alongside talented professionals, contributing to an exciting array of projects that will challenge your skills and help you grow.

About Checkout.com Checkout.com helps businesses succeed in the digital economy. Leading companies such as eBay, ASOS, Klarna, Uber Eats, and Sony rely on our platform to process seamless online payments. Our global network supports billions of transactions each year, focusing on reliability and ease of use. Headquartered in London, Checkout.com operates from 19 offices across six continents. The company values high performance and continuous improvement. Working here means contributing to the future of fintech alongside teams striving for excellence. Role Overview: Staff Software Engineer - Streaming The Data and AI Platform Team is looking for a Staff Software Engineer to help build a scalable platform for AI-driven streaming and batch data applications. This platform will improve how data is shared and used across Checkout.com, supporting business growth and performance. The team’s mission is to make it easier for internal teams to collect, store, process, and use data for impactful AI projects and data products. The focus is on reducing technical overhead so engineers can spend more time solving business challenges, not managing infrastructure or deployments. Current work lays the foundation for systems that will scale to support hundreds of teams and handle petabytes of data. Main Responsibilities Design and develop a highly available event streaming platform using technologies like Kafka and Flink. Offer technical leadership and mentorship, providing strategic direction and building strong relationships with engineers and managers across the organization. Work with cross-functional teams to deliver data solutions that support business goals. Location This role is based in London.

Join Carta, a leading financial technology company, as a Staff Software Engineer. In this role, you will contribute to the development of innovative software solutions that empower companies to manage their equity and ownership structures more effectively. You will collaborate with cross-functional teams, leveraging the latest technologies to deliver robust and scalable applications.

Join our innovative team at Astronomer as a Staff Software Engineer specializing in Data. In this role, you will help shape the future of data engineering solutions that empower organizations to harness the full potential of their data. You will work collaboratively with cross-functional teams to design, develop, and optimize data pipelines and infrastructure, ensuring high performance and reliability.

Position OverviewInnovation in the corporate world is undergoing a transformation. The existing systems designed to cultivate and safeguard innovation are unable to keep pace with rapid changes. Currently, 90% of the value of S&P 500 companies is intangible, primarily in the form of intellectual property, yet R&D and IP teams devote 50% of their time on tedious manual tasks, navigating through patents and documentation instead of advancing new ideas. Our mission is to revolutionize this process.At Ankar, we are developing the AI operating system for innovation, transforming how organizations create and secure their inventions. Our platform streamlines the transition of ideas into defensible intellectual property through a comprehensive suite of AI-powered modules, including patent drafting, office action responses, and infringement detection.We are at a pivotal moment:We have raised over $24M from leading venture capitalists such as Atomico, Index Ventures, and Norrsken, along with notable angel investors like the Founder of Hugging Face and executives from Datadog and OpenAI.Our clientele includes some of the world's most innovative firms, such as Fortune 500 giant L’Oréal and the global law firm Vorys.We are expanding our exceptional team, which includes alumni from Palantir, Amazon, and BCG, to tackle the immense $1T+ innovation market. We are just getting started.We are looking for driven individuals to join our team who are ready to take ownership of challenging projects, address complex high-impact problems, and achieve their best work. This role is perfect for a Senior Software Engineer/Tech Lead who excels in ownership, speed, and influence, and who desires to develop products in close collaboration with users.Key Responsibilities:Create exceptional products. Design, build, and maintain scalable, reliable systems and user-centric product experiences that our customers rely on.Transform complex challenges into reliable software. Utilize first principles to convert ambiguous requirements into clear, maintainable, production-ready solutions.Deliver swiftly and iterate continuously. Launch quickly, gather real feedback, and refine the product iteratively with direct customer input.Oversee complete project execution. Assume full responsibility for projects encompassing frontend, backend, and deployment—from design to implementation.

Role Overview Utility Warehouse is looking for a Staff Software Engineer to focus on Energy. This role shapes the design and implementation of software that supports our energy services. The position calls for both technical leadership and hands-on development. What You Will Do Design and build software solutions for energy products and services Guide engineers to deliver reliable, maintainable code Promote sustainability and efficiency in technical decisions Impact This position supports Utility Warehouse’s goal of improving the energy sector with technology. Staff Engineers in this area influence both the technical direction and the quality of delivery across teams.

Join Us in Revolutionizing the Fashion Supply Chain!Each year, the fashion industry generates over 100 billion garments, with a staggering 60% ending up in landfills. This waste isn't due to lack of demand; rather, the secondhand fashion supply chain is outdated, manual, and inefficient.At Fleek, we are dedicated to transforming this reality. Our goal is to establish secondhand fashion as the preferred choice for consumers. We are developing an innovative infrastructure that empowers the global secondhand clothing market through a B2B marketplace and AI-driven systems that streamline the supply chain.Fleek enables vintage boutiques, online resellers, and retail buyers to access high-quality graded secondhand inventory directly from wholesalers and rag houses worldwide. Central to our operations is FleekSort, an advanced AI model specifically trained on secondhand fashion, capable of grading, pricing, and categorizing items using just a photo. This technology transforms what has traditionally been a fragmented and manual trade into a cohesive, searchable, and tradable global inventory system.Since our inception in 2022, we have successfully diverted 9 million items from landfills and have experienced consistent year-on-year growth. With approximately $50 million raised from distinguished investors including a16z, Y Combinator, Burda Principal Investments, and HV Capital, we have recently completed our Series B funding round. Our advisors and private investors include industry veterans from Depop, Shopify, and Postmates.Currently, we serve thousands of resellers and retailers across the UK, Europe, and the US. With the secondhand fashion market projected to soar to $350 billion by 2027, Fleek is poised to become the AI-driven operational and financial backbone of secondhand commerce on a global scale.We are in search of passionate individuals eager to build impactful solutions and thrive in a fast-paced environment. If this excites you, continue reading!About This RoleAs the most senior engineering position within our organization, you will oversee the Demand product, which is crucial for driving revenue, growth, and customer engagement across mobile, web, and backend platforms. You will lead a talented team of approximately five engineers based in London, report directly to our CTO, Sanket Agarwal (formerly of Google and Postmates), and collaborate closely with our Product and Design teams.You will be responsible for everything that affects buyer conversion, retention, and growth speed.Why This Role Is UniqueAt Fleek, the Demand function is our most commercially vital area. You will not merely offer advice as a Staff engineer; you will have ownership over the entire system that transforms supply into revenue.Fleek is at the forefront of digitizing an industry that has yet to embrace technology. There are no established guidelines for creating a transaction layer around secondhand fashion at a wholesale scale, where each item is distinct...

About AirwallexAirwallex stands as the only integrated payments and financial platform tailored for global enterprises. Our unique blend of proprietary infrastructure and innovative software empowers over 200,000 businesses globally, including industry leaders like Brex, Rippling, Navan, Qantas, and SHEIN, offering fully integrated solutions for managing business accounts, payments, spend management, treasury, and embedded finance on a worldwide scale.Established in Melbourne, our team comprises more than 2,000 of the brightest minds in the tech industry across 26 global offices. Valued at US$8 billion and supported by world-renowned investors such as T. Rowe Price, Visa, Mastercard, Robinhood Ventures, Sequoia, Salesforce Ventures, DST Global, and Lone Pine Capital, Airwallex is at the forefront of constructing the global financial and payments platform of the future. If you are prepared to engage in the most ambitious work of your career, we invite you to join us.

Our VisionAt Omnea, we are passionately transforming the enterprise landscape, specifically tackling the complexities of procurement. Our goal is to eliminate the lengthy processes that often involve over 50 emails and the engagement of multiple departments such as Finance, Legal, Security, and IT just to secure a simple purchase approval.With a significant investment of $75M from Khosla Ventures, Insight Partners, and Accel, we are set on a mission to revolutionize this space. Our AI-driven platform seamlessly integrates all stakeholders, automating approvals and renewals, managing supplier risks in real-time, and providing complete visibility into spending.The procurement market is valued at over $7B, and our remarkable progress demonstrates the potential: we have achieved a tenfold increase in ARR to double-digit millions within just 18 months, working with esteemed global clients like Spotify, MongoDB, Monzo, and Albertsons. We are proud to be recognized as the 4th fastest growing startup in Europe.Our team boasts experience from scaling Tessian (a cybersecurity tech firm supported by Sequoia, Balderton, and Accel, acquired post-Series C), including former founders and operators who have led unicorn companies and developed top-tier products. You will collaborate with distinguished leaders such as Ben, Abs, Sabrina, and Rebe.What We SeekWe are on the lookout for an outstanding, product-oriented Team Leader - Staff Software Engineer (L4) to enhance our engineering team and navigate Omnea through this exciting growth phase. In the upcoming year, we aim to double our team size, expand our enterprise client base from approximately 100 to over 200, and triple our revenue. This Staff-level position offers a significant opportunity for domain-level influence, combining senior technical leadership with team management duties. You will guide a team, mentor engineers, and shape architectural and product decisions across a broader domain while remaining actively engaged in critical areas.You will be joining us at a critical juncture as we have just secured a $50M funding round to further our mission...

At Fastly, we are dedicated to enhancing connectivity to the digital experiences that matter most to our users. Our cutting-edge edge cloud platform empowers our clients to rapidly and securely deliver exceptional digital solutions by processing, serving, and securing applications close to their end-users — right at the edge of the Internet. Built to leverage the modern internet, our platform is highly programmable and supports agile software development, serving a roster of prestigious clients such as GitHub, Yelp, Paramount, and JetBlue.Join us in our mission to create a more trustworthy Internet.Posting Open Date: 24 March, 2026Anticipated Posting Close Date*: 20 April, 2026*Job posting may close early due to the volume of applicants.Staff Software Engineer, Compute PlatformOur team is responsible for developing the Compute platform at Fastly — an advanced serverless solution built on open standards operating on our extensive global edge network. This platform meets the demands of modern application development, enabling customers to execute code in a secure environment with microsecond cold start times, at scale, right on the edge.We are seeking a talented Staff Software Engineer to join our dynamic team and help enhance our hosting infrastructure. This role will encompass essential networking and systems-level tasks, as well as cross-team collaboration and the design of high-quality APIs for our customers to leverage services developed by other teams. You will also have the opportunity to contribute to influential open-source projects (such as Wasmtime) that play a pivotal role in our Compute vision.What You'll Do:Facilitate seamless communication and coordination among team members and across various technical and product teams.Engage in code reviews to enhance the codebase and improve team processes.Lead projects from a technical standpoint, driving progress and keeping stakeholders informed on project status.Develop platform-level code in Rust that addresses host concerns such as back pressure, resource limits, and service interactions.Investigate and resolve performance and stability challenges to meet stringent scalability requirements.Take ownership of a large-scale production system characterized by exceptional performance and availability needs.

About G2 - The CompanyG2 stands as the premier global software marketplace, renowned for empowering businesses to achieve their utmost potential through insightful data from genuine software users. By joining G2, you become part of an elite team dedicated to harnessing real user insights to influence strategic decisions.In an exciting merger with Capterra, SoftwareAdvice, and GetApp, we are now the largest repository of online software insights, catering to over 200 million visitors annually and featuring over 6 million verified reviews. Our goal is to enable software buyers to make informed decisions swiftly and confidently.We're just getting warmed up! Our mission is to revolutionize the global B2B software sector, establishing ourselves as the most reliable data source for software buyers and sellers in the AI era.Are you ready to embark on this thrilling journey with us? Join G2 as we scale new heights!About G2 - Our PeopleAt G2, our culture is deeply rooted in our PEAK values—(Performance + Entrepreneurship + Authenticity + Kindness). Being part of G2 means you are contributing to a value-driven, growing global community that supports each other in overcoming challenges and celebrating successes. Together, we tackle ambitious projects that foster personal and professional growth.You will collaborate with a diverse, global team comprising talented and dedicated individuals, each bringing unique experiences and aspirations. Our people-led ERGs play a crucial role in highlighting the diverse identities within our community. We prioritize DEI (Diversity, Equity, Inclusion) and philanthropic initiatives, such as our G2 Gives program, fostering a culture where we all strive to become better individuals.