Senior Backend Engineer

WHO WE ARE  We’ve been obsessed with brains. We believe everyone deserves a sharper, healthier mind. More than 100 million people turn to Lumosity to boost focus, strengthen memory, and think faster — making brain training part of their everyday lives. We also support the Human Cognition Project, collaborating with over 90 university partners to advance research in cognitive training.  We’re here to do the best work of our lives — building products that make minds sharper and healthier. Join us and help shape the future of brain health.  WHAT WE’RE LOOKING FOR  In this role, you’ll work closely with fellow engineers to design and build software at scale, reaching a large consumer audience. You’ll also collaborate with product managers, designers, scientists, and other stakeholders. We’re looking for someone with a strong history of shipping successful products and a genuine passion for cognitive health and wellness. KEY RESPONSIBILITIES Lead by example through high-quality, scalable code that solves complex problems. Contribute and influence system-level architecture and design decisions, working collaboratively with team members Design, implement and own scalable distributed systems that meet maintainability, scalability and performance demands Lead the definition of implementation details (the “how”) by working with engineering teammates Build and scale systems using our core stack: Node.js, TypeScript, GraphQL, Postgres, Kafka, AWS (Lambda, EKS, RDS) Collaborate on technical specifications and implementation plans Partner with product managers and stakeholders to define precise product requirements Champion best engineering practices and propose strategies for continued improvement Participate in agile processes and continuously evolve them for better efficiency Mentor and guide junior engineers through code reviews, technical discussions, and knowledge sharing Lead cross-team initiatives to define and standardize architectural patterns that enhance system scalability and resilience WHO YOU ARE A developer at heart with a knack for clean, maintainable, well-documented code that aligns with modern standards A system thinker capable of designing and evolving high-level architecture Self-starter — motivated to take initiative and own outcomes end-to-end Collaborative team player who thrives in small teams A continuous learner — willing to evolve technically and professionally Empathetic communicator — respects diverse perspectives and communicates ideas clearly Risk-aware — proactively identifies and mitigates technical or architectural risks Comfortable navigating ambiguity, and excited to bring clarity Passionate about creating meaningful, user-centric products A technical leader who can guide architectural decisions and mentor teammates Share the same vibe as we do WHAT YOU HAVE 7+ years of backend development experience in production environments Proven experience with distributed systems and system design principles Skilled in building Microservices, RESTful, and GraphQL APIs using modern tech stacks Strong working knowledge of relational (e.g., Postgres) and non-relational databases Proficient in Node.js, TypeScript, or similar backend languages Familiarity with modern CI/CD tools and automation pipelines Solid experience using AWS, particularly with Lambda, EKS (Elastic Kubernetes Service), RDS (Relational Database Service), and other cloud-native services Strong ability to analyze and convert business requirements into scalable technical solutions Proven track record in shipping performant, scalable software used by large audiences Prior startup experience is a bonus Experience driving cross-functional technical efforts and setting long-term architectural direction Proven ability to mentor and support the growth of junior and mid-level engineers Deep expertise in performance tuning and scaling distributed backend systems WHAT WE OFFER  The excitement and flexibility of an early-stage startup with the stability of a mature business Competitive salary AI is in our DNA. From Cursor to ChatGPT, v0 to Claude, we use cutting-edge tools to focus on the things that matter Hybrid work model: 3 days a week in office, designed for deeper collaboration and the fun of working side-by-side. Expect spontaneous whiteboard sessions, team lunches, and regular board-game hangouts Flexible paid time off Comprehensive, company-sponsored medical insurance (including spouse, children and parents/in-laws) Annual learning stipend for courses, books, and upskilling Office commute expense reimbursement and a location just a short walk from the nearest metro Set in a lively neighborhood with plenty of cafés and hangout spots to explore after work Monthly fitness/wellness reimbursements Catered lunches and a fully stocked pantry — complete with the real MVP: strong South Indian filter coffee. And a library nook stacked with books you’ll actually want to read Free Lumosity Family subscription — finally, a way to settle once and for all who’s the real genius in the family