Senior Backend Engineer We’re looking for Senior Backend Engineers to join our Platform team. This team builds and evolves the backend systems at the core of our products and customer-facing solutions. In this role, you’ll design and operate distributed systems, work with Web3 infrastructure, and collaborate closely with product and platform engineers to deliver reliable, scalable solutions. We value strong ownership, thoughtful system design, and a high bar for code quality. If you enjoy building solid systems, moving fast without cutting corners, and using modern tools (including AI) to work more efficiently, you’ll feel right at home with us.\nWhat You’ll Do Design, build, and maintain scalable distributed backend systems powering platform and product capabilities. Own backend services end-to-end: from architecture and implementation to monitoring and long-term reliability. Work closely with product and engineering peers to actively shape product decisions — not just execute specs. Build and evolve Web3 platform backend components, including protocol integrations, support for newly emerging blockchain networks, and reliable interactions with smart contracts. Ensure high standards of code quality, performance, security, and observability. Operate comfortably in a fast-paced startup environment, balancing speed and correctness. Leverage AI-assisted tools to improve development velocity, code quality, and personal productivity. Contribute to technical discussions, reviews, and mentorship within the engineering team. What We’re Looking For 5+ years of experience designing and building distributed backend systems. Strong foundation in algorithms, data structures, and software design patterns. Hands-on Web3 experience is a plus: Blockchain systems, dApps, Smart contracts. Strong ownership mindset — you take responsibility for outcomes, not just tasks. Clear, proactive communication in a distributed, async-first team. Ability to make pragmatic decisions: knowing when to move fast vs. go deep. High learning velocity and adaptability, especially when new tools or approaches (including AI-driven ones) improve results. Technical Skill Set Experience with containerized systems: Docker & Kubernetes. Databases: Postgres (SQL), MongoDB, Cassandra (NoSQL). Monitoring & observability: Sentry, Prometheus, Grafana. Hands-on experience with AWS. Experience with Python 3. Knowledge of Golang is a plus Bonus Points Prior experience working in a startup environment with high trust and autonomy. Located in time zones close to Europe. Strong collaboration skills and respect for diverse perspectives. Curiosity and willingness to challenge existing solutions when better ones exist. Thoughtful use of AI as a productivity multiplier, while maintaining a deep understanding of underlying systems and trade-offs. Interview Process Screening Call – 30 minutes Hiring Manager Interview – 45 minutes Technical Interview – 60 minutes System Design Interview – 90 minutes Team Interview – 60 minutes Founders Call – up to 60 minutes Reference Check \nWhy You Should Join Company Overview Zerion Wallet 1.7M+ active funded wallets 27.6M+ transactions 2.5B+ transaction volume 416K+ unique holders of Zerion DNA NFT Zerion API Trusted by 43 top crypto brands as paying clients Powering 405 active projects monthly Over 3.1B total requests processed Zerion Rewards (Loyalty Program) 167K+ wallets claimed retrodrop XP 837K+ quests completed Culture: Our culture shines through in our strong team engagement and impressive retention, showing just how much we value creating a workplace where people truly want to stay and thrive. People: Collaborate with some of the most driven and intelligent individuals in the crypto space. Salary & Benefits: Receive a competitive salary, medical insurance, coworking membership, and additional benefits. Unlimited Days Off and Flexible Work Schedule: Recharge and explore life outside the office with our flexible time-off policy and work schedule. Remote Work Essentials: We provide all the necessary software and equipment to ensure you're fully equipped to work from home comfortably and efficiently. Stock Options: Contribute to Zerion's success and watch your stock options become valuable. Relocation: We support relocation for you and your family. Travel: Join your colleagues on trips to industry festivals and events. Distributed Team: Zerion is a fully remote team with members worldwide. Embrace asynchronous collaboration, find your own work rhythm, and enjoy a healthy work-life balance. To ALL recruitment agencies and individual recruiters: Zerion only accepts resumes from its partners, with whom Zerion has contractual relations. Zerion is not responsible for any fees or charges associated with unsolicited resumes.