Senior Fullstack Engineer - TypeScript / Next.js / Supabase

Location: Bosnia and Herzegovina; Serbia; Georgia; Romania; Hungary; Croatia About Huzzle At Huzzle, we connect exceptional talent with top opportunities at leading companies across the UK, US, Canada, Europe, and Australia. Our clients include startups, digital agencies, and tech platforms in industries such as SaaS, MarTech, FinTech, and HealthTech. Unlike an outsourcing agency, we place you directly with a client where you’re hired in-house as a valued member of their team. About the Company Our client is a fast-growing technology company building multiple SaaS platforms across AI, healthcare, and data intelligence. Their core product is a multi-tenant AI-powered platform designed to enhance sales intelligence and call analysis, alongside a HIPAA-aware healthcare portal and a growing audience intelligence platform. They operate in a highly technical, product-driven environment focused on scalability, clean architecture, and efficient execution. Role Type: Full-time Engagement: Independent Contractor Job Summary We are hiring a Full-Stack Software Engineer to work across multiple SaaS applications, contributing to feature development, integrations, debugging, and backend systems. This is a high-impact remote engineering role where you’ll split your time across products based on sprint priorities, with a primary focus on an AI-driven platform. You’ll be responsible for executing scoped tasks with precision while also contributing to more complex systems and integrations. Key Responsibilities AI Sales Intelligence Platform (Primary Focus – ~70%) Build and implement features from architectural specifications Develop modern UI components, dashboards, and workflows using React and Next.js Build and maintain API routes with validation, pagination, and error handling Debug and maintain third-party integrations and APIs Implement webhook pipelines and asynchronous data workflows Manage background jobs and workflow orchestration Contribute to database design, migrations, and row-level security (RLS) policies Write unit and integration tests to ensure system reliability Healthcare B2B Platform (~30%) Develop onboarding flows and role-based interfaces Build and maintain authentication systems Integrate with third-party healthcare and pharmacy APIs Implement validation, audit logging, and compliance-aware features Troubleshoot bugs and improve system workflows Additional Product Work (As Needed) Support feature enhancements and maintenance for a stable audience intelligence platform General Responsibilities Execute development tasks with high reliability and attention to detail Collaborate through Git-based workflows, PR reviews, and structured documentation Troubleshoot API, integration, and system-level issues Use AI tools to improve development efficiency and output quality Requirements Core Technical Skills 2–4+ years of experience with TypeScript (strict mode, generics, strong typing) Strong experience with Next.js (App Router, API routes, middleware) Proficiency in React with modern component architecture Solid experience with PostgreSQL (queries, joins, schema design, RLS) Experience with Supabase or similar BaaS platforms (auth, database, storage, edge functions) Technical Experience REST API integrations and debugging Handling third-party API inconsistencies and failures Webhooks and asynchronous data processing Background jobs and workflow orchestration Git workflows (feature branches, pull requests, code reviews) Nice to Have Experience with multi-tenant SaaS platforms Exposure to AI or voice-based systems Experience working with HIPAA-compliant or regulated environments Strong understanding of system design and integration patterns How You’ll Work Async-first communication environment Documentation-driven development All code reviewed via pull requests before merging Strong focus on clean, reliable execution over unnecessary complexity Collaborative team culture with encouragement to ask questions early Growth Opportunity Increased ownership across systems and architecture Opportunity to lead projects and step into senior responsibilities Exposure to multiple SaaS products across AI, healthcare, and data platforms Ideal Candidate Detail-oriented and highly reliable Strong problem-solver, especially in debugging complex systems Comfortable working independently within structured systems Clear and proactive communicator Able to balance speed with high-quality output Benefits 💰 Competitive salary based on experience and region 🌎 Fully remote role with flexible working environment 🚀 Work on cutting-edge AI and multi-product SaaS platforms 📈 Long-term growth with opportunities for leadership and ownership 🧠 Exposure to complex systems, integrations, and scalable architectures 🎯 High-impact role contributing directly to product development