Senior Software Engineer

Software Engineer (Full Stack / AI) - Helsinki, FinlandWe're partnering with an innovative, venture-backed technology company that's transforming how sustainable materials are bought and sold across Europe.Leveraging AI-powered trading technology, the business is helping industrial manufacturers make recycled materials the default choice instead of the difficult one. Since launching in 2023, the company has grown rapidly, supplying recycled materials to hundreds of manufacturing businesses across multiple European countries while building a unique dataset that powers increasingly intelligent decision-making and automation.As growth accelerates, they're looking to hire a Senior Software Engineer to strengthen their product team and help build the technology platform at the heart of the business.This is an exciting opportunity for a Full Stack Software Engineer who enjoys working in a fast-moving startup environment where technology directly impacts business success.You'll be joining a close-knit product team responsible for building the digital infrastructure that supports trading operations, logistics, AI-driven workflows, and customer-facing products. The role combines traditional software engineering with modern AI development, offering the chance to work on real-world applications of LLMs, intelligent automation, and agent-based systems.You'll work closely with founders, commercial teams, and end users, taking ownership of products from concept through to business impact.What You'll Be DoingDevelop and maintain full-stack applications across React frontends and Node.js backendsDesign and build scalable features used daily by customers and internal teamsWork extensively with PostgreSQL databases, including schema design, migrations, and performance optimisationDeploy and manage infrastructure on Google Cloud Platform using TerraformDesign and implement AI-powered workflows, agents, and automation solutionsCollaborate directly with users and commercial stakeholders to identify and solve business challengesInfluence engineering standards, architecture decisions, and best practices as the team growsTake ownership of features from idea through deployment and measurable business outcomesTechnology StackNode.jsTypeScriptReactPostgreSQLGoogle Cloud Platform (GCP)TerraformGitHub ActionsAI / LLM IntegrationsAgent-based AI ArchitecturesEssential Experience4+ years of software engineering experienceStrong TypeScript development experienceProven experience building modern web applicationsAbility to work across the full stack with confidenceStrong backend engineering capabilitiesExperience working with cloud-based applications and infrastructureExcellent communication and collaboration skillsNice to HaveExperience with Google Cloud PlatformInfrastructure-as-Code experience using TerraformExposure to AI-native development, including:LLM APIsAI agentsRetrieval systemsTool integrationsWorkflow automationStartup or scale-up experienceThis role would suit someone who:Wants to build products rather than simply deliver ticketsEnjoys collaborating closely with end users and business stakeholdersTakes ownership and responsibility for outcomesThrives in ambitious, fast-growing startup environmentsIs excited by the practical application of AI technologiesBalances engineering quality with delivery speedWants their work to contribute toward sustainability and environmental impactYou'll be joining a team that:Solves genuine customer problems rather than building features in isolationShips quickly, learns from feedback, and continuously improvesGives engineers end-to-end ownership of their workEncourages cross-functional collaboration and initiativeValues curiosity, accountability, humility, and continuous learningProvides direct access to founders and leadershipFocuses on impact rather than hierarchyWhy Join?Mission-driven business helping accelerate sustainability and the circular economyOpportunity to work with cutting-edge AI technologies in production environmentsDirect influence on product strategy and technical directionEquity opportunity alongside salarySmall, highly talented product team where your contributions are visibleExposure to the full lifecycle of building and scaling a technology companyCollaborative and entrepreneurial cultureModern technology stack and greenfield product development opportunitiesIdeal BackgroundMid-level to Senior Full Stack EngineersBackend Developers looking to broaden their technical scopeEngineers interested in AI-native product developmentStartup-minded developers who enjoy ownership and autonomyDevelopers seeking a mission-led company where technology has a measurable real-world impactIf you're excited by sustainability, startups, and building intelligent software products that solve real-world challenges, we'd love to hear from you.