Senior Backend Engineer (Node.js)

About Us Scramblyis one of the fastest-growing adtech startups in the world, featured in the AppsFlyer Performance Index and Singular ROI Index in just 3.5 years. We’re growing 250%+ YoY across revenue, team, product, and technology — fully bootstrapped and profitable. We’re building the future of app discovery: a reward-powered alternative to the App Store and Google Play. Our loyalty-driven ecosystem connects millions of users with the world’s top apps and delivers unmatched, ROI-focused growth for mobile advertisers. Our mission is to build a true alternative to traditional app stores — fueled by rewards and data — and create a new, performance-first growth engine for mobile app advertisers. About the Role We are looking for a Senior Backend Engineer to join the team building the core systems behind Scrambly. In this role, you will work across two key areas: user-facing product systems, solving complex scalability challenges for a platform serving millions of users globally; and theinternal platform, covering admin systems, tooling, and back-office automation that power our operations team. Your focus will be on writing robust, high-performance code and bridging the gap between product requirements and technical reality. You will work within a modern tech stack to ensure our systems remain fast, reliable, and easy to maintain as we grow. Key Responsibilities Design & Implementation Design, build, and maintain high-performance, scalable backend services and APIs using Node.js (NestJS) Write clean, maintainable, and testablecode that serves as a benchmark for the team Ensure seamless integration between backend services and frontend applications Architecture & Technical Strategy Propose and implement architectural improvements for core systems Design complex features with a focus on long-term scalability, extensibility, and maintainability Apply best practices for distributed systems and RESTful API design Mentorship & Code Quality Champion high code quality and engineering best practices across the team Mentor other engineers through constructive code reviews, technical guidance, and pair programming Foster a culture of technical curiosity and continuous improvement Performance & Infrastructure Monitor system performance, identify bottlenecks, and proactively resolve reliability issues Collaborate with DevOps to ensure smooth CI/CD pipelines, deployments, and infrastructure reliability Work with containerization and orchestration tools to manage application lifecycles Cross-functional Collaboration Work closely with Product, Design, Frontend, and QA teams to deliver high-quality features Translate product requirements into robust technical specifications Communicate technical constraints and trade-offs clearly to non-technical stakeholders Requirements 5+ years of software engineering experience, with a strong focus on backend development Strong proficiency in Node.js and modern frameworks like NestJS Excellent system design skills and a solid understanding of backend architecture, RESTful APIs, and distributed systems Experience with cloud platforms (GCP preferred; AWS or Azure acceptable), containerization (Docker), and orchestration/IaC (Kubernetes, Terraform, Helm) Proficiency with relational (e.g., PostgreSQL), NoSQL (e.g., Redis) databases, and message queues (e.g., RabbitMQ, GCP Pub/Sub, Redis Pub/Sub) Hands-on experience with React, capable of implementing basic UI features for internal tools independently Strong communication and collaboration skills, comfortable working in a fast-paced team environment English: Upper-Intermediate or higher (B2/B2+, written and spoken). You need to be able to communicate clearly in English to work effectively in an international team and participate in architectural discussions Nice to Have Experience in a B2C startup that has scaled to millions of users Basic proficiency in Go; able to read, write, and maintain basic Go services without starting to learn from scratch What We Offer Work on systems where performance optimizations translate to immediate user impact for millions of users A culture of code reviews, knowledge sharing, and mentorship where the best idea wins A fast-paced environment where your code quickly translates into real user value We value the stability and value of what you ship, not just the number of lines of code Flexible, remote-friendly working environment 15 days of paid vacation 5 days of paid days off 5 days of paid sick leave Maternity/Paternity leave National holidays based on your country of stay Originally posted on Himalayas