Senior Backend Engineer About UsEvery business needs to know who they’re really working with whether it’s suppliers, investors, partners, or third parties. At Xapien, we’re reinventing how organisations do that, combining speed, scale and accuracy with cutting-edge AI.Since 2018, we’ve grown from a deep-tech startup to a global player in AI-driven due diligence and risk intelligence. 2024 was a landmark year as we closed a $10M Series A, earned recognition in the Chartis RiskTech100® and Everest Group’s Leading 50™, and expanded our products, markets and customer base.2025 was even bigger: With new regulations, rising compliance pressure and growing reputation risks, organisations everywhere are demanding smarter, faster ways to work and they’re turning to us. Customers worldwide from global law firms and private banks to universities and nonprofits rely on Xapien to turn days of manual research into trusted insights, delivered in minutes.Our momentum so farCustomers in a diverse range of industries, with particular growth in wealth management, financial services and supply chain onboarding.Demand accelerating beyond our UK headquarters, across multiple continents with new customers in the Middle East, Asia, and Oceania.Why this is an exciting time to joinThis isn’t just another job role; it’s an opportunity to shape the future of the due diligence industry with a market-leading product trusted by global organisations. Whether you’re in marketing, communications, sales, or finance, you’ll play a critical role in driving growth, building credibility, and defining how we connect our product to a rapidly evolving market.We’re scaling fast with more customers, more releases, and bigger regulatory and market challenges. Expectations are rising, due diligence now means real-time insight, delivered efficiently and with impact. You won’t just be executing campaigns, closing deals, or managing numbers, you’ll be influencing strategy, optimising processes, and helping position a brand that’s setting the new standard for trust and transparency.For people who love learning, innovating, and making an impact that matters now is the moment to be a part of Xapien.The RoleWe're hiring a Staff Backend Engineer to join our engineering team in a high-impact technical leadership role. You'll work on our most challenging technical problems, own parts of our platform’s architecture, and help shape the technical direction of our backend stack.Our tech stack center’s on Go microservices, with Temporal workflows, MongoDB and ElasticSearch running on Kubernetes in GCP. You'll work with modern patterns including event-driven architectures, gRPC and REST APIs, and comprehensive observability with Grafana Cloud.You'll take technical ownership of major domains within our platform - whether that's our Investigations pipeline (web scraping, data provider integrations, LLM-powered analysis) or our Core App systems (user journeys, features, and configuration). You'll be a technical authority, establishing patterns that others follow and driving initiatives that span multiple teams.What You'll DoOwn the technical direction and architecture for parts of our platformDesign and build complex backend services and systems that scaleDrive technical decisions that affect multiple teamsEstablish patterns, standards, and best practices that others will followLead complex technical initiatives from design through implementationIdentify and address systemic technical challenges across our backendWrite exemplary Go code that sets the standard for quality and designMentor engineers across the organization, raising the technical barBalance technical excellence with pragmatic deliveryInfluence technology choices and architectural directionCollaborate with engineering leadership on technical strategyBuild new systems and features while improving our existing architectureWhat We're Looking ForEssential10+ years of professional software engineering experienceDeep expertise in Go, with mastery of concurrency, performance optimization, and advanced patternsProven track record of designing and owning large-scale systemsStrong experience with distributed systems, event-driven architectures, or similar complex systemsDeep understanding of databases, particularly MongoDB or similar NoSQL systemsExtensive experience with microservices architecture and inter-service communicationExpert-level understanding of containerization (Docker) and orchestration (Kubernetes)Experience establishing technical standards and patterns across teamsStrong architectural thinking with ability to balance trade-offsTrack record of mentoring and developing other engineersAbility to drive technical initiatives with minimal guidanceExperience influencing technical direction at an organizational levelExcellent communication skills with ability to articulate complex technical conceptsHighly DesirableExperience with Temporal or similar workflow orchestration systems at scaleDeep knowledge of event streaming platforms like KafkaExperience with LLMs and AI integration (particularly for Investigations team)Background in SaaS platforms or B2B products at scaleExpert-level knowledge of observability tools (Grafana, Prometheus, etc.)Deep understanding of authorization patterns, security, and multi-tenancyExperience with protobuf and gRPCOur Tech StackLanguages: GoDatabases: MongoDBMessaging & Orchestration: Temporal, KafkaAPIs: REST, gRPC, protobufInfrastructure: Kubernetes, GCPObservability: Grafana stackAI: LLMs (OpenAI, Gemini), RAG systemsWhat Success Looks LikeIn your first 6 months, you will have:Owned and driven a significant technical initiative to completionEstablished new patterns or improved existing ones across teamsMentored multiple engineers, visibly raising technical standardsContributed to architectural decisionsBeen recognized as a technical authority in your domainMade measurable improvements to system reliability, performance, or scalabilityInfluenced the technic