Back End Developer Jobs

About Ubiquiti At Ubiquiti Inc., we create technology platforms for Businesses, Smart Homes, and Internet Service Providers, driven by our goal to connect everyone, everywhere. To date, Ubiquiti has shipped over 100 million devices worldwide, from ISP networking products to next generation of IT solutions. Our growth is made possible by the dedicated team of hundreds behind the scenes. From software developers and product managers to designers and strategists, Team UI is driven to achieve our common goal: Rethinking IT. At Ubiquiti, you’ll heighten your potential and broaden your horizons - all while shaping the future of connectivity. Join forces with us on our mission to build a better IT industry. We are currently looking for a highly skilled Backend Software Engineer (Node.js) to join our team in Stockholm or Malmö, Sweden. Please note that applicants must live in Sweden and hold a valid work permit at the time of application to be considered for this role. Responsibilities: Design, build, and maintain backend services in Node.js and TypeScript across systems and applications on UniFi Develop secure, scalable, and maintainable APIs and service workflows Contribute to architecture and code design decisions across the team Review code and help maintain strong engineering standards, release quality, and development workflows Investigate production issues, debug complex failures, and ship robust fixes Work closely with embedded, web, mobile, product, and design teams to deliver platform capabilities used across the UniFi ecosystem Improve the reliability, observability, and developer experience of the services you work on Requirements: 5+ years of professional experience with Node.js and TypeScript 3+ years of experience working with SQL databases such as PostgreSQL Experience building software for connected devices, infrastructure products, networking systems, or similarly complex environments Good understanding of web security, including OWASP, browser securi

About Navier AI Navier AI is building the first autonomous engineering agents. AI systems that can design, simulate, and optimize complex products to achieve breakthrough levels of performance. Our mission is to enable engineers to move beyond today’s slow, manual design cycles by providing agents that reason about physics, explore design trade-offs, and generate high-performance solutions across aerospace, automotive, and advanced manufacturing. We’re backed by top-tier investors and work directly with industry leaders to deploy AI-native tools that go far beyond today’s design automation. Role Overview We’re hiring a Backend Engineer to help build the infrastructure behind our autonomous engineering agents. You’ll work across model serving, simulation orchestration, multi-agent coordination, and developer-facing APIs. This role is critical to delivering fast, reliable, and scalable systems that engineers can trust in production design environments. Responsibilities Own core backend systems for serving AI agents and managing their compute, data, and model coordination Design and implement APIs that expose agent functionality—simulation control, CAD operations, optimization workflows—to internal tools and customer integrations Build secure, scalable infrastructure for multi-agent orchestration, including support for containerized workloads, caching, and distributed compute Collaborate closely with ML, frontend, and simulation engineers to create a cohesive, performant product experience Integrate external tools such as CAD software, simulation backends (e.g., OpenFOAM), and data stores into our pipeline Support agent development workflows, including tooling for versioning, introspection, and reproducibility Contribute to infrastructure decisions that will shape the technical foundation of our platform as it scales Engage directly with early customers to support integration, identify infrastructure needs, and gather feedback Qualifications Required: Strong backend en

Backend - Technical Lead About Us: Paytm is India’s largest digital payments and financial services platform, leading the mobile QR revolution. We power millions of businesses and individuals, and we’re building scalable, resilient systems to serve half a billion Indians and beyond. About the Role: 1) As a Technical Lead, you’ll not just write code — you’ll design scalable architectures, coach engineers, and lead technology-first projects. 2) You'll drive backend systems that support 100M+ DAUs, optimize APIs to sub-50ms latencies, and be a champion of engineering excellence. 3) We expect you to actively use AI tools to accelerate architecture design, code reviews, prototyping, and developer productivity. What We're Looking For: 1) 4 to 6 ears of hands-on backend engineering experience — Java/Nodejs. 2) Proven ownership of high-scale distributed systems. Deep knowledge of microservices, messaging systems, caching, storage optimization, and cloud scalability. 3) Clear architectural thinking; you can design systems for billions of transactions, not just millions. 4) An AI-first mindset — you should know how to augment yourself with GPT and other AI coding tools to move 2x faster. 5) Strong leadership skills — mentoring, code reviewing, pushing for engineering best practices. Why You Should Join Us: 1) Massive ownership and real-world system building opportunities. 2) Work with AI, not against it — code smarter, architect smarter, and build smarter. 3) We are a pure tech-driven team inside Paytm — no unnecessary meetings, no bureaucracy. 4) You’ll work on critical platforms, live user-impacting systems, and future-proof engineering. Preferred Qualifications : Bachelor's/Master's Degree in Computer Science or equivalent

Backend - Technical Lead About Us: Paytm is India’s largest digital payments and financial services platform, leading the mobile QR revolution. We power millions of businesses and individuals, and we’re building scalable, resilient systems to serve half a billion Indians and beyond. Here at Paytm, technology isn't just about keeping up, it's about building the future. We believe the next generation of engineers must not only scale systems to billions but also leverage AI and GPT tools to accelerate innovation About the Role: 1) As a Technical Lead, you’ll not just write code — you’ll design scalable architectures, coach engineers, and lead technology-first projects. 2) You'll drive backend systems that support 100M+ DAUs, optimize APIs to sub-50ms latencies, and be a champion of engineering excellence. 3) We expect you to actively use AI tools to accelerate architecture design, code reviews, prototyping, and developer productivity. What We're Looking For: 1) 4 to 6 years of hands-on backend engineering experience — Java, Spring Boot, AWS.) 2) Proven ownership of high-scale distributed systems. Deep knowledge of microservices, messaging systems, caching, storage optimization, and cloud scalability. 3) Clear architectural thinking; you can design systems for billions of transactions, not just millions. 4) An AI-first mindset — you should know how to augment yourself with GPT and other AI coding tools to move 2x faster. 5) Strong leadership skills — mentoring, code reviewing, pushing for engineering best practices. Why You Should Join Us: 1) Massive ownership and real-world system building opportunities. 2) Work with AI, not against it — code smarter, architect smarter, and build smarter. 3) We are a pure tech-driven team inside Paytm — no unnecessary meetings, no bureaucracy. 4) You’ll work on critical platforms, live user-impacting systems, and future-proof engineering. Ideal Profile 1) Obsessed with system scale, performance, and reliability. 2) Already

Backend - Technical Lead About Us: Paytm is India’s largest digital payments and financial services platform, leading the mobile QR revolution. We power millions of businesses and individuals, and we’re building scalable, resilient systems to serve half a billion Indians and beyond. Here at Paytm, technology isn't just about keeping up, it's about building the future. We believe the next generation of engineers must not only scale systems to billions but also leverage AI and GPT tools to accelerate innovation About the Role: 1) As a Technical Lead, you’ll not just write code — you’ll design scalable architectures, coach engineers, and lead technology-first projects. 2) You'll drive backend systems that support 100M+ DAUs, optimize APIs to sub-50ms latencies, and be a champion of engineering excellence. 3) We expect you to actively use AI tools to accelerate architecture design, code reviews, prototyping, and developer productivity. What We're Looking For: 1) 5+ years of hands-on backend engineering experience — Java, Spring Boot, AWS.) 2) Proven ownership of high-scale distributed systems. Deep knowledge of microservices, messaging systems, caching, storage optimization, and cloud scalability. 3) Clear architectural thinking; you can design systems for billions of transactions, not just millions. 4) An AI-first mindset — you should know how to augment yourself with GPT and other AI coding tools to move 2x faster. 5) Strong leadership skills — mentoring, code reviewing, pushing for engineering best practices. Why You Should Join Us: 1) Massive ownership and real-world system building opportunities. 2) Work with AI, not against it — code smarter, architect smarter, and build smarter. 3) We are a pure tech-driven team inside Paytm — no unnecessary meetings, no bureaucracy. 4) You’ll work on critical platforms, live user-impacting systems, and future-proof engineering. Ideal Profile 1) Obsessed with system scale, performance, and reliability. 2) Already usin

About Us At LangChain, our mission is to make intelligent agents ubiquitous. We build the foundation for agent engineering in the real world, helping developers move from prototypes to production-ready AI agents that teams can rely on. We began as widely adopted open-source tools and have grown to also offer a platform for building, evaluating, deploying, and operating agents at scale. With $125M raised at Series B from IVP, Sequoia, Benchmark, CapitalG, and Sapphire Ventures, we’re at a stage where we’re continuing to develop new products, growth is accelerating, and all team members have meaningful impact on what we build and how we work together. LangChain is a place where your contributions can shape how this technology shows up in the real world. Today, our platform includes LangSmith (Observability, Evaluation, Deployment, Fleet, and Sandboxes), our open source frameworks (LangChain, LangGraph, and Deep Agents), and the newly launched LangSmith Engine for autonomous agent improvement. We have 100M+ monthly open source downloads, 6,000+ active LangSmith customers, and 5 of the Fortune 10 use LangSmith in production (+ 35% of the Fortune 500 overall), including teams at Klarna, Clay, Coinbase, Workday, Lyft, Cloudflare, Harvey, Rippling, Vanta, LinkedIn, Monday.com, Nvidia, and Bridgewater. About The Team The LangSmith team owns and builds LangChain's core platform for observability, evaluation, and production reliability of AI systems. From tracing and annotation to run rules, evaluations, and beyond, this team owns LangSmith end-to-end. If you want to define what great AI observability looks like at production scale, this is where that work gets done. About The Role We are looking for a Senior Backend Engineer to join us. In this role you will be building the backend systems that power LangChain’s observability and evals platform. You will work on the core services that allow developers to monitor and evaluate their AI applications at scale. While the focus is

About Us At LangChain, our mission is to make intelligent agents ubiquitous. We build the foundation for agent engineering in the real world, helping developers move from prototypes to production-ready AI agents that teams can rely on. We began as widely adopted open-source tools and have grown to also offer a platform for building, evaluating, deploying, and operating agents at scale. With $125M raised at Series B from IVP, Sequoia, Benchmark, CapitalG, and Sapphire Ventures, we’re at a stage where we’re continuing to develop new products, growth is accelerating, and all team members have meaningful impact on what we build and how we work together. LangChain is a place where your contributions can shape how this technology shows up in the real world. Today, our platform includes LangSmith (Observability, Evaluation, Deployment, Fleet, and Sandboxes), our open source frameworks (LangChain, LangGraph, and Deep Agents), and the newly launched LangSmith Engine for autonomous agent improvement. We have 100M+ monthly open source downloads, 6,000+ active LangSmith customers, and 5 of the Fortune 10 use LangSmith in production (+ 35% of the Fortune 500 overall), including teams at Klarna, Clay, Coinbase, Workday, Lyft, Cloudflare, Harvey, Rippling, Vanta, LinkedIn, Monday.com, Nvidia, and Bridgewater. About The Team The LangSmith team owns and builds LangChain's core platform for observability, evaluation, and production reliability of AI systems. From tracing and annotation to run rules, evaluations, and beyond, this team owns LangSmith end-to-end. If you want to define what great AI observability looks like at production scale, this is where that work gets done. About The Role This role is based onsite in Boston, MA. We are looking for a Senior Backend Engineer to join our growing engineering team in Boston. In this role you will be building the backend systems that power LangSmith, LangChain’s observability and evals platform. You will work on the core services that all

GitLab is the intelligent orchestration platform for DevSecOps. GitLab enables organizations to increase developer productivity, improve operational efficiency, reduce security and compliance risk, and accelerate digital transformation. More than 50 million registered users and more than 50% of the Fortune 100* trust GitLab to ship better, more secure software faster. The same principles built into our products are reflected in how our team works: we embrace AI as a core productivity multiplier, with all team members expected to incorporate AI into their daily workflows to drive efficiency, innovation, and impact. GitLab is where careers accelerate, innovation flourishes, and every voice is valued. Our high-performance culture is driven by our values and continuous knowledge exchange, enabling our team members to reach their full potential while collaborating with industry leaders to solve complex problems. Co-create the future with us as we build technology that transforms how the world develops software. * Fortune 500® is a registered trademark of Fortune Media IP Limited, used under license. Claim based on GitLab data. Fortune 100 refers to the top 20% ranked companies in the 2025 Fortune 500 list, published in June 2025. Fortune and Fortune Media IP Limited are not affiliated with, and do not endorse products or services of GitLab. An overview of this role As a Backend Engineer on the Plan: Spec-Driven Development team, you'll help build GitLab's intent-to-code loop: agentic workflows that turn a stated intent into a refined work item, an implementation plan, and verified, mergeable code. You'll own early-stage backend work across the flows, application programming interfaces, data models, and evaluation systems behind this experience, using Ruby on Rails, Python, PostgreSQL, GitLab Duo Agent Platform, large language model application programming interfaces, and an artificial intelligence gateway. You'll join a small, distributed team working on one of GitL

GitLab is the intelligent orchestration platform for DevSecOps. GitLab enables organizations to increase developer productivity, improve operational efficiency, reduce security and compliance risk, and accelerate digital transformation. More than 50 million registered users and more than 50% of the Fortune 100* trust GitLab to ship better, more secure software faster. The same principles built into our products are reflected in how our team works: we embrace AI as a core productivity multiplier, with all team members expected to incorporate AI into their daily workflows to drive efficiency, innovation, and impact. GitLab is where careers accelerate, innovation flourishes, and every voice is valued. Our high-performance culture is driven by our values and continuous knowledge exchange, enabling our team members to reach their full potential while collaborating with industry leaders to solve complex problems. Co-create the future with us as we build technology that transforms how the world develops software. * Fortune 500® is a registered trademark of Fortune Media IP Limited, used under license. Claim based on GitLab data. Fortune 100 refers to the top 20% ranked companies in the 2025 Fortune 500 list, published in June 2025. Fortune and Fortune Media IP Limited are not affiliated with, and do not endorse products or services of GitLab. An overview of this role As a Backend Engineer on the Plan: Spec-Driven Development team, you'll help build GitLab's intent-to-code loop: agentic workflows that turn a stated intent into a refined work item, an implementation plan, and verified, mergeable code. You'll own early-stage backend work across the flows, application programming interfaces, data models, and evaluation systems behind this experience, using Ruby on Rails, Python, PostgreSQL, GitLab Duo Agent Platform, large language model application programming interfaces, and an artificial intelligence gateway. You'll join a small, distributed team working on one of GitL

Engineering Manager - Backend About Us: Paytm is India’s leading digital payments and financial services company, which is focused on driving consumers and merchants to its platform by offering them a variety of payment use cases. To merchants, Paytm offers acquiring devices like Soundbox, EDC, QR and Payment Gateway where payment aggregation is done through PPI and also other banks’ financial instruments. To further enhance merchants’ business, Paytm offers merchants commerce services through advertising and Paytm Mini app store. Operating on this platform leverage, the company then offers credit services such as merchant loans, personal loans and BNPL, sourced by its financial partners. About the role: As a Engineering Manager, you will help define the technical design and implementation roadmap across multiple solutions and will work with engineering leadership to ensure we resource and equip our squads with the right expertise to deliver those solutions. Requirements: 8 to 12 years of strong software design/development experience in building massively large scale distributed internet systems and products Hands on experience in Advance Java, Spring boot, AWS, Node, Agentic AI, LLM, RAG, Cursor, Copilot Experience and knowledge of open source tools & frameworks, broader cutting edge technologies around server side development Should be an active contributor to developer communities like Stack overflow, Top coder, Git hub, Google Developer Groups (GDGs). Superior organization, communication, interpersonal and leadership skills. Must be a self-starter who can work well with minimal guidance and in fluid environment. Preferred Qualifications : Bachelor's/Master's Degree in Computer Science or equivalent Skills that will help you succeed in this role: Expertise in Java, DB: RDBMS, Messaging: Kafka/RabbitMQ, Caching: Redis/Aerospike, Micro services, AWS Strong experience in scaling, performance tuning & optimization at both API and storage layers Probl

Principal Engineer - Backend About Us: Paytm is India’s leading digital payments and financial services company, which is focused on driving consumers and merchants to its platform by offering them a variety of payment use cases. To merchants, Paytm offers acquiring devices like Soundbox, EDC, QR and Payment Gateway where payment aggregation is done through PPI and also other banks’ financial instruments. To further enhance merchants’ business, Paytm offers merchants commerce services through advertising and Paytm Mini app store. Operating on this platform leverage, the company then offers credit services such as merchant loans, personal loans and BNPL, sourced by its financial partners. About the role: As a Principal Engineer, you will help define the technical design and implementation roadmap across multiple solutions and will work with engineering leadership to ensure we resource and equip our squads with the right expertise to deliver those solutions. Requirements: 8 to 12 years of strong software design/development experience in building massively large scale distributed internet systems and products Hands on experience in Advance Java, Spring boot, AWS, Node, Agentic AI, LLM, RAG, Cursor, Copilot Experience and knowledge of open source tools & frameworks, broader cutting edge technologies around server side development Should be an active contributor to developer communities like Stack overflow, Top coder, Git hub, Google Developer Groups (GDGs). Superior organization, communication, interpersonal and leadership skills. Must be a self-starter who can work well with minimal guidance and in fluid environment. Preferred Qualifications : Bachelor's/Master's Degree in Computer Science or equivalent Skills that will help you succeed in this role: Expertise in Java, DB: RDBMS, Messaging: Kafka/RabbitMQ, Caching: Redis/Aerospike, Micro services, AWS Strong experience in scaling, performance tuning & optimization at both API and storage layers Problem

SpaceX was founded under the belief that a future where humanity is out exploring the stars is fundamentally more exciting than one where we are not. Today, SpaceX is actively developing the technologies to make this possible, with the ultimate goal of making life multiplanetary and expanding consciousness to the stars. SpaceXSI is building Super Intelligence to help humanity understand the universe. Our teams are building the full Super Intelligence stack: from our Colossus supercomputers, to Grok models, to our suite of applications, including Grok Bot, Grok Build, Grok Imagine, Grok Voice, and X. We're creating a powerful flywheel where more compute trains better models, better models power more useful products, and what we learn from people using those products shapes what we build next. ABOUT THE ROLE: As an ideal candidate you have a good understanding of how highly scalable and reliable production infrastructure is built. Most of our backend infrastructure is written in Rust. So familiarity with a compiled language such as C++, Rust, or Go is highly beneficial. RESPONSIBILITIES: Build the SpaceXSI API that serves our models to developers worldwide Own the end-to-end system responsible for high-throughput inference, handling billions of tokens per minute with low latency and high availability, including model serving infrastructure, request routing, SDK development, rate limiting, observability, and efficient scaling BASIC QUALIFICATIONS: Expert knowledge of either Rust or C++ Experience in designing, implementing, and maintaining reliable and horizontally scalable distributed systems Knowledge of service observability and reliability best practices Experience in operating commonly used databases such as PostgreSQL, Clickhouse, and MongoDB PREFERRED SKILLS AND EXPERIENCE: Experience with LLM inference engines and serving frameworks (e.g., SGLang, TensorRT, vLLM) Experience designing or building with agent SDKs and agent orchestration frameworks Experience with

HackerRank helps companies like NVIDIA, Amazon, and Microsoft hire and upskill the next generation of developers based on skills, not pedigree. Our platform is trusted by over 2,500 of the world’s most innovative companies to build strong engineering teams ready for what’s next. Software has entered an era where humans and AI build side by side. As this shift accelerates, the definition of strong technical talent is changing. We give companies better ways to identify and invest in next-generation skills. People at HackerRank care deeply about the impact of their work and sweat the small details so our customers can be wildly successful with products they genuinely love to use. We move with urgency and believe great outcomes come from high standards. About the role Every day, millions of developers use HackerRank to prove their skills. We're looking for a Senior Backend Software Development Engineer who can drive the technical direction of critical backend systems and lead the delivery of high-impact, platform-level initiatives. You will own the architecture and evolution of core backend services, mentor engineers across teams, and be a key technical decision-maker ensuring our platform remains fast, reliable, and scalable as we grow our global user base. What you’ll do Architect, design, and lead the implementation of complex backend systems and services that power core product experiences at scale. Define and drive technical strategy for your domain, making key decisions on system design, technology choices, and long-term architectural direction. Own the end-to-end reliability and performance of critical backend services, establishing SLOs, monitoring, and incident response best practices. Design scalable API frameworks and data models that serve as foundations for multiple product teams and external integrations. Lead cross-functional technical initiatives spanning multiple teams, coordinating with frontend, infrastructure, product, and design stakeholders. Identi

A World-Changing Company Palantir builds the world’s leading software for data-driven decisions and operations. By bringing the right data to the people who need it, our platforms empower our partners to develop lifesaving drugs, forecast supply chain disruptions, locate missing children, and more. The Role Backend Software Engineers at Palantir build software at scale to transform how organisations use data. Our Software Engineers are involved throughout the product lifecycle, from idea generation, design, prototyping, and production delivery. You will collaborate closely with technical and non-technical teammates to understand our customers' problems and build products that solve them. We encourage movement across teams to share context, skills, and experience, so you'll learn about many different technologies and aspects of each product. Engineers work autonomously and make decisions independently, within a community that will support and challenge you as you grow and develop, becoming a strong technical contributor and engineering leader. Our Product Development organisation is made up of small teams of Software Engineers. Each team focuses on a specific aspect of a product. Our infrastructure teams are responsible for the lowest layers of our software stack, often focused on database technologies, distributed systems, large scale data systems, security, and application infrastructure. As a Software Engineer on infrastructure, you'll contribute high-quality code to underpin Palantir Foundry and Gotham with performant, secure, and scalable building blocks, enabling products deployed to the most important institutions in the public and private sector. You'll build the foundational capabilities that power our products used by research scientists, aerospace engineers, intelligence analysts, and economic forecasters, in countries around the world. We’re hiring engineers who are passionate about solving real-world problems and empowering both developers and

HackerRank helps companies like NVIDIA, Amazon, and Microsoft hire and upskill the next generation of developers based on skills, not pedigree. Our platform is trusted by over 2,500 of the world’s most innovative companies to build strong engineering teams ready for what’s next. Software has entered an era where humans and AI build side by side. As this shift accelerates, the definition of strong technical talent is changing. We give companies better ways to identify and invest in next-generation skills. People at HackerRank care deeply about the impact of their work and sweat the small details so our customers can be wildly successful with products they genuinely love to use. We move with urgency and believe great outcomes come from high standards. About the role Every day, millions of developers use HackerRank to prove their skills. We're looking for a Senior Backend Software Development Engineer who can drive the technical direction of critical backend systems and lead the delivery of high-impact, platform-level initiatives. You will own the architecture and evolution of core backend services, mentor engineers across teams, and be a key technical decision-maker ensuring our platform remains fast, reliable, and scalable as we grow our global user base. What you will do Architect, design, and lead the implementation of complex backend systems and services that power core product experiences at scale. Define and drive technical strategy for your domain, making key decisions on system design, technology choices, and long-term architectural direction. Own the end-to-end reliability and performance of critical backend services, establishing SLOs, monitoring, and incident response best practices. Design scalable API frameworks and data models that serve as foundations for multiple product teams and external integrations. Lead cross-functional technical initiatives spanning multiple teams, coordinating with frontend, infrastructure, product, and design stakeholders. Iden