Software Engineer - Member of Technical Staff

About ApturaAptura is at the forefront of building reliable AI systems through expertly crafted evaluation datasets and reinforcement learning environments. Our mission is to create robust training data and verifiable task environments in high-stakes industries such as finance, healthcare, and legal. We are a dynamic, small team based in London, dedicated to making significant contributions and innovating quickly. Each team member plays a pivotal role, and we value initiative and ownership. If you're passionate about shaping the future of AI in real-world applications, we want to hear from you.About the RoleAs a Member of the Technical Staff within our Software Engineering team, you will develop the platform that supports Aptura’s operations and scalability. Your responsibilities will encompass the creation of annotation tools, workflow systems, quality control pipelines, and the internal infrastructure that underpins every dataset and environment we produce.Your daily tasks will include designing expert task creation flows, developing task assignment and review interfaces, constructing data pipelines to convert expert outputs into structured training datasets, and integrating LLM-powered tools directly into our product. Your work will span product engineering and infrastructure, ensuring that the software you develop enables our small team to deliver high-quality evaluation data at scale.You will be instrumental in bringing our platform vision to life, determining what features to build and how to build them, while establishing our development standards as we expand.What You'll DoTake ownership of the core data annotation and workflow platform from task assignment to dataset delivery.Create systems that facilitate expert onboarding, task routing, review workflows, and quality assurance at scale.Enhance AI-integrated pipelines across the platform, including LLM-assisted annotation and automated checks.Collaborate directly with founders and domain experts to transform manual processes into scalable software solutions.Make informed product and engineering decisions in fast-paced, ambiguous environments, prioritizing effectively and shipping products without waiting for perfect specifications.Contribute to defining our team’s approach to development, including tooling, engineering practices, and product strategy.Who We're Looking ForWe seek a proactive individual who excels in ambiguous environments and thrives on the challenge of defining projects without strict specifications. If you enjoy problem-solving and have a strong foundation in software engineering, you will fit well within our team.

About MentisAt Mentis, we are dedicated to creating reliable AI solutions for critical sectors such as finance, healthcare, and legal. Our team specializes in developing meticulously curated evaluation datasets and reinforcement learning environments. We empower AI labs and startups by providing them with expertly crafted training data, calibrated assessment rubrics, and rigorous task environments to push the boundaries of AI capabilities in regulated industries.As a tight-knit team based in London, we pride ourselves on our agility and commitment to excellence. Every member plays a vital role in our mission, and we value initiative and ownership in our collaborative work culture. If you are passionate about shaping the future of frontier AI applications, we want to hear from you.About the RoleAs a Software Engineer and Member of Technical Staff, you will be instrumental in building and scaling the platform that drives Mentis' operations. You will develop essential annotation tools, workflow systems, quality control pipelines, and internal infrastructure fundamental to every dataset and environment we deliver.Your daily tasks will include designing expert task creation workflows, creating task assignment and review interfaces, developing data pipelines to convert expert outputs into structured training sets, and integrating LLM-powered tools into our product. Your role will vary from product engineering to infrastructure development, with a consistent focus on producing high-quality evaluation data at scale.You will take ownership of the platform's development, making key decisions on what features to build, how to implement them, and establishing the standards for our growth.What You'll DoDevelop and manage the core data annotation and workflow platform from start to finish, overseeing task assignment, expert interfaces, quality control, and dataset delivery.Design systems that facilitate expert onboarding, task routing, review workflows, and scalable quality assurance processes.Enhance AI-integrated pipelines across the platform, including LLM-assisted annotation, automated checks, and model-in-the-loop workflows.Collaborate directly with founders and domain experts to streamline bespoke processes into effective, scalable software solutions.Make informed product and engineering decisions in a dynamic environment, prioritizing and shipping features without waiting for perfect specifications.Contribute to defining our team’s development practices, including tooling choices, engineering standards, and product strategy.Who We're Looking ForWe seek a proactive individual who thrives in fast-paced environments and embraces ambiguity. If you are excited about the opportunity to influence how AI learns and operates in real-world settings, we welcome your application.

About OpenCoreOSA High-Performance Ledger: We deliver an ultra-efficient ledger built on Go, Rust, and multi-region distributed databases, providing banks with a robust, adaptable, and open framework for development, rather than a restrictive monolithic structure.AI-Integrated Solutions: AI is not merely an enhancement; it's an integral aspect of our system architecture. We leverage AI to facilitate autonomous operations, create dynamic development workflows, and establish a self-optimizing platform.Reliability and Openness: Our focus is on achieving five-nines reliability and unwavering consistency, designed to support Tier-1 banks that handle hundreds of millions of transactions daily. By utilizing open technologies and forging new standards, we promote innovation without imposing lock-in constraints.Leadership with Proven Expertise: Our leadership team merges the strategic vision of former McKinsey banking, product, and engineering specialists with the real-world experience of a founder who developed and scaled a mission-critical fintech solution for the world's largest banks. This is complemented by insights from ex-global bank CIOs, providing us with an unmatched understanding of the evolving market landscape.Your RoleLedger Engine: Develop a deterministic, event-sourced transaction engine.Interest & Pricing Engine: Perform high-precision financial calculations.Reconciliation Engine: Ensure invariants, controls, and cross-ledger consistency.Operational Data Store (ODS): Manage a real-time operational data plane.Scalability Layer: Address concurrency, throughput, partitioning, and replication challenges.AI-Driven Development Experience: Work with MCP servers, agent workflows, and automated runbooks.Your Key ResponsibilitiesCreate initial MVPs for Tier-1 banks.Design distributed systems leveraging Go, Kafka, and distributed SQL databases.Manage systems throughout the entire SDLC (coding, testing, DevOps, infrastructure, product development).Implement advanced CI/CD practices and testing automation.

About the Role XAI is hiring a Member of Technical Staff for the X Money team in London. This role focuses on building and improving financial technology products that support the company's mission. What You Will Do Design, develop, test, and deploy software features for the X Money platform Work closely with engineers and other professionals to deliver reliable and secure solutions Help ensure the platform meets standards for performance, scalability, and security Who We’re Looking For Technical staff with a strong interest in financial technology Comfortable taking on challenging projects and collaborating with others Ready to contribute ideas and take ownership of solutions Location This position is based in London, UK.

About H:H is at the forefront of advancing superintelligence through agentic AI. Our mission is to automate complex, multi-step tasks usually undertaken by humans, empowering AI agents to unlock the full potential of human capabilities.We are on the lookout for the brightest AI minds who are as committed to building safely and responsibly as they are to pushing the boundaries of disruptive agentic technologies. At H, we foster a culture of openness, continuous learning, and collaboration, where every voice contributes to our shared success.About the Team: The Infrastructure team is dedicated to providing seamless access to the necessary infrastructure for our research and engineering teams. We ensure that the foundational infrastructure for our public services is robust, reliable, and scalable, positioning Infra team members to influence every aspect of H, from foundational model development to agent creation and public service delivery.Key Responsibilities:Design and manage infrastructure to support:Research initiatives in model and agent development, including training infrastructure, data pipelines, and inference capabilities.Product engineering efforts on H's agent platform, encompassing client-facing APIs and agent runtimes across multiple deployment scenarios (multi-tenant and on-premises).Establish and maintain observability and monitoring strategies.

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 OpenCoreOS as a Systems Engineer!At OpenCoreOS, we redefine banking technology with our innovative, hyper-performant ledger solutions. Utilizing cutting-edge programming languages like Go and Rust, along with multi-region distributed databases, we empower financial institutions to build on a robust, open foundation instead of a cumbersome monolithic structure.Why Choose Us?Designed for AI: AI isn't just an add-on; it's integrated into our operations, enhancing autonomous workflows and creating intelligent, self-healing systems.Unyielding Reliability: We aim for five-nines reliability to ensure our platform can handle the scale of Tier-1 banks, managing millions of daily transactions without compromising consistency.Industry Expertise: Our leadership team merges strategic insights from seasoned banking professionals with practical experience, ensuring we understand the market dynamics we are transforming.Your Role:Core Financial Systems: Develop mission-critical services ensuring accurate value recording and transfer.Transaction Processing: Create reliable transaction flows that maintain integrity during retries and partial failures.Performance Optimization: Profile and enhance key pathways to ensure predictable latency and scalable throughput.Reliability & Observability: Advance metrics, tracing, logging, and incident readiness for our production systems.AI-Enhanced Development: Utilize and refine AI-driven workflows for improved debugging, operations, and developer efficiency.Core Responsibilities:Manage production systems from start to finish.Enforce safety and correctness through rigorous testing and change management.Troubleshoot distributed and system-level challenges (concurrency, performance, data consistency).

Join xai as a Technical Staff Member focusing on Model Training. In this role, you will collaborate with a talented team to develop and optimize machine learning models that drive innovative solutions. Your expertise will contribute to enhancing the performance of our systems and delivering impactful results.

Join Cohere as a valued member of our technical staff, focusing on the safety of our agents. In this critical role, you will be responsible for designing, implementing, and maintaining safety protocols that ensure the integrity and security of our systems. Collaborate with cross-functional teams to develop innovative solutions that enhance agent safety and improve operational efficiency.

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.

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.

About ApturaAptura specializes in creating evaluation datasets and reinforcement learning (RL) environments that enhance the reliability of AI across high-stakes sectors such as finance, healthcare, and legal domains. Our dedicated team curates expert training data, develops calibrated evaluation rubrics, and constructs verifiable task environments tailored for AI labs and startups that are innovating within regulated industries.As a compact and agile team based in London, we prioritize speed and take our work seriously. Each team member plays a crucial role, where initiative is celebrated, and ownership is a fundamental expectation. If you aspire to influence how advanced AI systems learn to function in real-world applications, we encourage you to apply.About the RoleIn the role of a Technical Staff Member on our Applied AI team, you will create the tasks and environments essential for AI labs to train and assess their agents across finance, healthcare, and legal sectors.Your daily responsibilities will include constructing RL environments using spreadsheets, documents, and professional workflows. You will develop verification logic and reward functions, collaborating closely with domain experts to define the criteria for accurate responses in complex models such as leveraged buyouts or clinical notes. Your work may oscillate between engineering and research, but the unifying objective is to deliver the ground truth against which leading models are evaluated.What You'll DoDevelop RL environments tailored to the finance, healthcare, and legal sectors.Collaborate in creating tasks with definitive answers, calibrated evaluation criteria, and automated reward signals.Design verification logic and reward functions to differentiate between effective and ineffective model outputs.Engage with domain experts (investment analysts, healthcare professionals, attorneys) to convert intricate professional workflows into structured tasks.Prototype innovative methods for evaluation, verification, and synthetic data generation.Who We're Looking ForHands-on experience with large language models (LLMs): including prompting, evaluation, and agentic harnesses. You have developed functional systems instead of merely theoretical models.High initiative and technical proficiency. You don’t wait for permission, specifications, or a detailed plan. You identify what needs to be accomplished, determine how to achieve it, and execute effectively.Ability to adapt to varied contexts. Your role will involve switching between engineering tasks, evaluation design, and close collaboration with domain experts frequently within a single day.You are proactive in shipping and iterating. In our small team, there’s no room for work that remains in limbo.

Omaze connects communities in the UK and Germany with the chance to win luxury homes and life-changing prizes, while raising significant funds for charities. In just five years, Omaze has helped generate over £100 million for organizations including Age UK, the RSPCA, British Heart Foundation, and Great Ormond Street Hospital Charity. The company continues to grow, aiming to drive social impact on a global level. Role overview The Staff Software Engineer role at Omaze in London focuses on technical leadership and engineering strategy for platforms supporting social good. This position covers architectural design, software delivery, and team leadership. The engineer will influence both what gets built and how development happens, with a strong emphasis on developer experience, code quality, and sound engineering practices. What you will do Set and maintain engineering standards, patterns, and best practices across the stack, including TypeScript, AWS, and React. Lead the architecture of complex, cross-functional systems, making decisions that improve performance, scalability, security, and maintainability. Identify and address technical risks early, and drive architectural improvements that streamline processes and increase efficiency. Shape the company's approach to AI-assisted coding by evaluating tools, defining responsible integration standards, and embedding AI into workflows for CI/CD, code review, and testing. Guide the design of agentic systems, focusing on observability, human oversight, and safe autonomy limits. Translate broad business goals into actionable technical solutions. What sets Omaze apart Significant growth as a company with a mission-driven focus. Collaboration with a team committed to making a meaningful difference. Opportunities to work on innovative projects and initiatives. A culture that values hard work, mutual support, and shared success.

About Us:Lunar is an innovative technology company operating in stealth mode, dedicated to developing a transformative software platform for health systems. Our mission is to redefine healthcare with state-of-the-art, AI-driven software that empowers hospitals to provide exceptional care to their patients. Our platform serves as the foundational backbone of modern health systems, revolutionizing clinical and operational workflows on a large scale with the world’s first AI-native hospital information system.This next-generation platform represents a thorough reconstruction of the information infrastructure that supports health systems. From doctors and nurses to pharmacists, lab technicians, coders, billers, and supply chain personnel, as well as patients, Lunar’s software is designed to enhance every aspect of healthcare delivery. We view this challenge as the 'moon landing' of healthcare—an ambitious undertaking that many deem impossible.Supported by leading venture capital firms from Silicon Valley, we champion the effectiveness of a compact, high-performing team of experienced professionals working at the top of their game. We seek individuals who are driven, inquisitive, possess sound judgment, and are committed to producing the best work of their careers.Our hospitals operate on Elixir. We have adopted Elixir for its fault tolerance, concurrency, and scalability—critical attributes for managing real-time patient data in essential environments such as Emergency Departments, ICUs, and Operating Rooms.We are on the lookout for a Staff Software Engineer who is eager to confront some of the most challenging technical issues in healthcare and do so as part of a small, agile, and purpose-driven team. If you take pride in writing clean, resilient code and are enthusiastic about reinventing the software infrastructure for contemporary hospitals, we would love to connect with you.Key Technical Challenges You May Encounter in Your First Six Months:Building a Modern Cloud Architecture from the Ground Up: We have no legacy systems to unravel. We are designing a cutting-edge cloud-native platform centered around Elixir.Developing a Superior Access Control System for Clinical Data: Create a modern access control system with precise permissions that honor clinical data structures and patient data ownership while facilitating population-level insights for enhanced public health.Ensuring Hospitals Remain Operational 24/7: Design and implement infrastructure capable of supporting rolling deployments, failover, and...

Our MissionAt Omnea, we are transforming the enterprise business landscape by addressing the most challenging aspects of procurement. Our aim is to streamline the purchase process, which often drags on for months, involves numerous emails, and requires input from various departments such as Finance, Legal, Security, and IT for approvals.With the backing of $75M from Khosla Ventures, Insight Partners, and Accel, we are revolutionizing this space. Our AI-driven platform integrates every stakeholder, step, and system to ensure that buying is swift, secure, and efficient—providing a singular destination for requests, automated approvals and renewals, real-time supplier risk analysis, and complete visibility of spending.This sector represents a $7B+ untapped market, and our growth trajectory underscores the potential: we have increased our ARR tenfold to double-digit millions in just 18 months, earning the trust of global enterprises like Spotify, MongoDB, Monzo, and Albertsons. Currently, we are recognized as the 4th fastest growing startup in Europe.Our team has previously scaled Tessian (cybersecurity technology backed by Sequoia, Balderton, Accel, and acquired post-Series C). We comprise ex-founders and operators who have successfully grown unicorns and delivered world-class products. You will collaborate with seasoned leaders like Ben, Abs, Sabrina, and Rebe.What We're Looking ForWe are on the lookout for an outstanding, product-oriented Staff Software Engineer (L4) to be a pivotal part of our engineering team and propel Omnea into its next growth phase. In the upcoming year, our team will double in size, our enterprise customer base will expand from around 100 to over 200, and our revenue is projected to triple. This role is for a senior individual contributor focused on domain-level impact, where you will utilize your deep technical expertise to influence systems, architecture, and product outcomes—without formal team leadership or people management obligations.You will join us at a critical juncture. We have recently secured $50M in Series B funding from ....

Location: LondonCompany: H About H H is focused on building agentic AI that automates complex, multi-step tasks typically handled by people. The company’s goal is to help individuals achieve more by creating superintelligent systems that work safely and responsibly. H values openness, continuous learning, and collaboration. Every team member’s input matters here. About the Models Team The Models team develops the core models that power H’s agentic AI technology. This group works on training methods to boost model performance and efficiency, especially for agent-driven applications where inference costs matter. Projects span Large Language Models (LLMs) and Vision-Language Models (VLMs), enabling agents to interpret and interact with complex environments. Team members refine these models using advanced training approaches, including reinforcement learning and reward modeling. The focus is on better instruction following, tool use, and dynamic interaction. The team’s work bridges research and product, turning new research into practical solutions that move AI forward. Who Hires Here H seeks exceptional AI researchers and engineers from around the world who care about advancing technology safely and responsibly. The company welcomes those eager to shape the future of superintelligent AI alongside a collaborative and driven team.

Who We AreSamsara (NYSE: IOT) is at the forefront of the Connected Operations™ Cloud, a transformative platform that empowers organizations reliant on physical operations to capitalize on Internet of Things (IoT) data. Our mission is to enhance the safety, efficiency, and sustainability of the foundational sectors driving the global economy. Representing over 40% of global GDP, these industries—including agriculture, construction, field services, transportation, and manufacturing—are critical infrastructure, and we are excited to lead their digital transformation.Joining Samsara means you will play a vital role in defining the future of physical operations. You'll collaborate with a dynamic team focused on developing innovative product solutions such as Video-Based Safety, Vehicle Telematics, Apps and Driver Workflows, and Equipment Monitoring. As a recently public company, we provide the autonomy and support needed to make a significant impact as we build for the long term.About the Role:In this newly established Staff Software Engineer position, you will design the technical architecture necessary for global fleet sustainability, focusing on digitizing the vast transport and infrastructure sectors that support our world. Our goal goes beyond traditional cost-saving measures; we prioritize resource efficiency on a global scale.At Samsara, our Staff Engineers are proactive technical leaders who integrate high-level architectural strategies with a determined builder mindset. They operate with empowered autonomy, addressing the most complex challenges at the intersection of physical and digital operations.Unlike conventional architects, they maintain a close connection to the implementation, actively contributing to the codebase to foster rapid innovation and sustain development momentum. Their leadership serves as a force multiplier, elevating the technical capabilities of the team through insightful mentorship and pragmatic decision-making, ensuring that every line of code has a measurable impact on the world’s essential industries.In this role, you will spearhead the technical strategy for our Sustainability suite—transforming raw, inconsistent sensor signals into high-fidelity data for precise energy monitoring, and constructing the intricate global infrastructure necessary for fleet electrification.

At Ripple, we are pioneering a transformative world where value transfers seamlessly, akin to the flow of information in today's digital landscape. Our vision is ambitious and impactful, and we are already making strides toward this goal. Through our innovative cryptocurrency solutions tailored for financial institutions, businesses, governments, and developers, we are enhancing the global financial ecosystem, fostering economic equity, and expanding opportunities for individuals across the globe. Join us to achieve remarkable professional growth and make a significant difference in the world of finance.If you are eager to witness your contributions in action and unlock exceptional career advancement opportunities, come aboard and help us create authentic value in the real world.The RoleAs a Staff Engineer specializing in Front End development, you will contribute to Palisade, Ripple's flagship wallet-as-a-service platform. This platform empowers businesses, fintech firms, and banks to create innovative digital asset treasury, payment, and exchange solutions.

Ebury is on a mission to empower ambitious businesses to achieve global growth. We extend the same philosophy to our team members, promoting innovation, collaboration, and problem-solving in an inclusive environment where everyone feels valued, supported, and empowered to thrive.If you are a collaborative individual eager to revolutionize global business operations, we encourage you to reach out. Join us at Ebury and accelerate your career while shaping the future of finance.Join Our Team as a Staff Software Engineer (Enabling Teams)Location: London Office - Hybrid: 4 days in the office, 1 day remoteEbury is seeking highly skilled and motivated Staff Software Engineers to enhance our engineering division in London. This is a remarkable opportunity to make a significant impact within a leading FinTech firm. As a Staff Software Engineer, you will be a crucial member of our team from day one, contributing to mission-critical projects and deploying production code within your first week. Your role will involve collaboration with various product squads alongside Engineers, Product Designers, and Product Managers. We expect you to tackle complex challenges and guide your team to make informed trade-offs. You will be immersed in both the intricate details and the overarching vision of our projects. Additionally, you'll play a pivotal role in engineering leadership and cultivate strong relationships with stakeholders across the organization. We are committed to identifying and nurturing future technical leaders; for those who exhibit exceptional performance and potential, we offer an accelerated career progression path.