Software Development Engineer III | Full stack - Wallet

About HighLevel HighLevel is a cloud-based, all-in-one white-label marketing and sales platform that empowers marketing agencies, entrepreneurs, and businesses to elevate their digital presence and drive growth. We are proud to support a global and growing community of over 1 million businesses, from marketing agencies to entrepreneurs to small businesses and beyond. Our platform empowers users across industries to streamline operations, drive growth, and crush their goals. HighLevel processes over 15 billion API hits and handles more than 2.5 billion message events every day. Our platform manages 470 terabytes of data distributed across five databases, operates with a network of over 250 micro-services, and supports over 1 million domain names. Our People With over 1,500 team members across 15+ countries, we operate in a global, remote-first environment. We are building more than software; we are building a global community rooted in creativity, collaboration, and impact. We take pride in cultivating a culture where innovation thrives, ideas are celebrated, and people come first, no matter where they call home. Our Impact Every month, our platform powers over 1.5 billion messages, helps generate over 200 million leads, and facilitates over 20 million conversations for the more than 2 million businesses we serve. Behind those numbers are real people growing their companies, connecting with customers, and making their mark - and we get to help make that happen. Learn more about us on our YouTube Channel or Blog Posts About the Role We’re looking for a Software Development Engineer III (SDE III) with strong backend expertise and enough full-stack capability to own features end-to-end. Must-have skills: Deep expertise in Node.js, MongoDB, Vue.js, and distributed systemsProven track record in building highly stable, scalable backend platformsComfortable contributing to the frontend when needed (this is not a UI-heavy role) What the role is really about (backend-heavy): You’ll join our Wallet team that powers Wallet, Billing, Taxes, and related services. Your focus will be on foundational, platform-level work:Ensuring rock-solid system stability and performance under growing loadDriving scalability, tech debt reduction, security hardening, and cost optimization Solving complex distributed systems challenges that keep the entire Wallet ecosystem reliable and efficient. This is a backend-first, full-stack role — you’ll spend most of your time on architecture, performance, and infrastructure while still being able to ship complete features when required. If you love deep backend problems and want to own the stability and scalability of a mission-critical product, this is for you. Responsibilities: Own end-to-end feature delivery for the Wallet, Billing & Taxes platform – from API design and backend implementation to necessary Vue.js frontend changes. Build and maintain highly stable, performant, and scalable backend services using Node.js, MongoDB, and distributed systems patterns. Identify and fix systemic issues (crashes, time-outs, race conditions, memory leaks, etc.) to improve overall platform reliability. Drive performance optimizations and cost-efficiency improvements (query tuning, caching strategies, indexing, reducing cloud spend). Actively reduce technical debt by refactoring critical parts of the codebase, improving test coverage, and eliminating anti-patterns. Implement and enforce security best practices (input validation, auth flows, secrets management, rate limiting, etc.) in every change. Enhance observability – add meaningful logs, metrics, alerts, and tracing to make issues easier to debug in production. Collaborate closely with QA from day one: review test cases, perform live demos during QA handover, and quickly address feedback. Contribute to internal tooling and automation that speeds up development and deployment cycles. Pair with other engineers, share knowledge, and help unblock teammates when needed. Participate in on-call rotation and resolve production incidents for the services you own. This is a hands-on IC role where you’ll write a lot of production code, ship frequently, and directly impact the stability and scalability of our Wallet platform. Requirements: 4–7 years of backend engineering experience with proven exposure to scale (high TPS, large datasets, or multi-tenant environments) Expert-level Node.js and a strong track record of writing clean, modular, reusable codeDeep expertise with MongoDB (complex schemas, aggregation pipelines, indexing, sharding) Solid production experience with Redis (caching, rate-limiting, pub/sub, distributed locks)Hands-on experience building and running microservices on Kubernetes (basic K8s knowledge is sufficient – deployments, services, configmaps, etc.) Strong hands-on experience with any major cloud provider (GCP, AWS, or Azure) – you know how to use managed services for containers, queues, caches, serverless, and databases effectively Comfortable contributing to the frontend using any modern UI framework (Vue.js, React, Angular – Vue.js experience is a plus but not mandatory) You’ve shipped and supported large-scale, mission-critical systems that stayed stable under heavy load. You love modular architecture, obsess over performance and cost on GCP, and can jump into the frontend when needed to ship complete features. Preferred Experience: Experience with AI Tools and contributions to open-source tools, internal platforms or engineering blogs NestJS or Express.js experience Elastic search for search/filtering use cases Exposure to any OLAP system (ClickHouse, Snowflake, BigQuery, etc.)