Staff Software Engineer I at StepStone · London

companyDescription At The Stepstone Group, we have a simple yet very important mission: The right job for everyone. Using our data, platform, and technology, we create opportunities for jobseekers and companies around the world to find a perfect match in fair and equitable way. With over 20 brands across 30+ countries, we strive for fair and unbiased hiring. Join our team of 3,000+ employees and be part of reshaping the labour market and becoming the world’s leading job platform. jobDescription About our Marketplace Enablement Org and User Dialogue Team Within Marketplace Enablement, we build the technology that helps candidates and recruiters find the right match. Our teams deliver data products, search and recommendations, and intelligent user dialogue capabilities using modern engineering practices, AI and cloud-native technology. Within this org, our User Dialogue team, are building the next generation of conversational and agentic AI experiences. This includes intelligent candidate engagement, personalised outreach, messaging journeys, and AI-powered systems that support users through complex recruitment journeys. By joining this team, you will be playing a vital role as together we reimagine the labour market to make it work for everybody. The Role We are recruiting for a Staff Software Engineer (AI) to help design, build and evolve production-grade agentic AI systems. This is a strategic, hands-on engineering leadership role focused on integrating Large Language Models into scalable, secure, reliable and observable architectures. This is an individual contributor leadership role with no direct line management responsibility. You will help move our agentic AI capabilities beyond experimentation and into dependable products that operate safely and effectively at scale across our global marketplace. Working closely with software engineers, machine learning engineers, data scientists, product managers, analysts and technical leaders, you will shape how we build, test, deploy, monitor and govern AI-powered systems. Success in this role will depend as much on influence and communication as on technical depth. You will need to create alignment across teams, explain complex concepts clearly, and help others make confident, pragmatic decisions. Your responsibilities As a Staff Software Engineer (AI), you will: Design, architect and build agentic and LLM-powered systems within our AWS environment, with a focus on production readiness, reliability, security and scale. Provide technical leadership across teams, helping move AI capabilities from R&D and experimentation into maintainable, observable and operationally robust products. Work closely with product managers, engineers, machine learning engineers, data scientists and technical leaders to align technical decisions with user needs, business priorities and long-term platform direction. Define and improve engineering standards, reusable patterns, tools, templates and best practices for building agentic AI systems responsibly and consistently. Lead the implementation and deployment of systems at scale, ensuring strong approaches to testing, monitoring, evaluation, guardrails, observability and operational support. Communicate architectural choices, trade-offs and technical risks clearly to technical and non-technical stakeholders. Mentor and coach engineers, raising the engineering bar across design, delivery, code quality, security, maintainability and pragmatic technical decision-making. Contribute to tech-wide initiatives, collaborating across the organisation to promote standardisation, responsible AI practices and strong engineering design. qualifications We are looking for a versatile Staff-level engineer with strong software engineering foundations and practical experience designing and delivering production-grade systems. Strong software engineering experience in Python and at least one of Java, TypeScript or .NET. Experience designing, building and operating distributed systems in AWS or comparable cloud platform. Practical experience integrating Large Language Models into production systems. Understanding of prompt orchestration, tool usage and LLM interaction patterns. Experience implementing state management, memory strategies, evaluation approaches and guardrails in AI systems. Experience with evaluation, observability and performance optimisation for LLM-powered systems. Experience using LLM APIs such as OpenAI, Bedrock or similar. Understanding of secure software development, data protection, compliance and enterprise architecture principles. Experience deploying and operating solutions on cloud platforms, preferably AWS. Excellent communication and influencing skills, with the ability to create shared understanding across technical and non-technical audiences. Experience mentoring engineers and raising standards across teams. additionalInformation We’re a community here that cares as much about your life outside work as how you feel when you’re with us. Because your job shouldn’t take over your life, it should enrich it. Here are some of the benefits we offer: 29 days holiday allowance + bank holidays Private medical and dental healthcare Matching pension contribution of 4 or 5% (after 3 years of service up to 10%) 24/7 Employee Assistance Programme Life Assurance Cover Cycle to work scheme Hybrid working model  (3 days working from the office) Volunteering days and you can bring your dog to the office on Mondays and Fridays! Our commitment Equal opportunities are important to us. We believe that diversity and inclusion at The Stepstone Group are critical to our success as a global company, so we want to recruit, develop, and keep the best talent. We encourage applications from everyone, regardless of background, gender identity, sexual orientation, disability status, ethnicity, belief, age, family or parental status, and any other characteristic. As a global business we further our DEI and sustainability progress by working with national and international bodies and are proud to have been recognised for our work - both locally and internationally, including: Armed Forces Covenant: Silver Award, Employer Recognition Scheme EcoVadis: Bronze Award Fertility Friendly Employer, accredited by Fertility Matters at Work RIDI (Recruitment Industry Disability) Awards: Inclusive Technology Award 2024 Stonewall: Gold Award Stonewall: Top 100 Workplace Equality Index (85)