Backend And System Engineer in United States

At ClickUp, we're building the future of work: the first truly converged AI workspace unifying tasks, docs, chat, calendar, and enterprise search, all supercharged by context-driven AI. We are an AI-native company. Every team member is expected to leverage AI daily, and we evaluate AI fluency as part of our hiring process. Join us and help redefine what's possible. 🚀 Role Overview: We are seeking a skilled and experienced Senior AI Engineer – AI Platform to join our ClickUp Engineering team. In this role, you will play a critical part in both building the core AI platform and directly applying large language models (LLMs) to deliver intelligent features across ClickUp. You will focus on backend systems that enable scalable, reliable, and secure AI-powered capabilities, while also working hands-on with LLMs to solve real user problems and drive product innovation. Key Responsibilities: Architect, design, and implement scalable AI platform services that support the deployment, orchestration, and lifecycle management of LLMs and other AI models. Apply LLMs and other AI technologies directly to build and enhance ClickUp’s intelligent features, working closely with product and engineering teams to deliver impactful solutions. Build and maintain robust APIs and backend systems that enable seamless integration of AI-powered features into ClickUp’s core platform. Develop infrastructure for model serving, monitoring, logging, and automated evaluation to ensure high reliability and performance of AI services in production. Integrate with multiple LLM providers (e.g., OpenAI, Anthropic, Google) and manage model selection, routing, and fallback strategies for optimal performance and cost. Drive the adoption of best practices in AI privacy, security, and compliance, including data anonymization, secure data handling, and regulatory adherence. Optimize platform performance, scalability, and cost-efficiency, leveraging cloud-native technologies and distributed systems. Stay curre

At ClickUp, we're building the future of work: the first truly converged AI workspace unifying tasks, docs, chat, calendar, and enterprise search, all supercharged by context-driven AI. We are an AI-native company. Every team member is expected to leverage AI daily, and we evaluate AI fluency as part of our hiring process. Join us and help redefine what's possible. 🚀 Role Overview: We are seeking a highly skilled Staff AI Engineer – AI Platform to join our ClickUp Engineering team. In this role, you will play a critical part in both building the core AI platform and directly applying large language models (LLMs) to deliver intelligent features across ClickUp. You will focus on backend systems that enable scalable, reliable, and secure AI-powered capabilities, while also working hands-on with LLMs to solve real user problems and drive product innovation. Key Responsibilities: Architect, design, and implement scalable AI platform services that support the deployment, orchestration, and lifecycle management of LLMs and other AI models. Apply LLMs and other AI technologies directly to build and enhance ClickUp’s intelligent features, working closely with product and engineering teams to deliver impactful solutions. Build and maintain robust APIs and backend systems that enable seamless integration of AI-powered features into ClickUp’s core platform. Develop infrastructure for model serving, monitoring, logging, and automated evaluation to ensure high reliability and performance of AI services in production. Integrate with multiple LLM providers (e.g., OpenAI, Anthropic, Google) and manage model selection, routing, and fallback strategies for optimal performance and cost. Drive the adoption of best practices in AI privacy, security, and compliance, including data anonymization, secure data handling, and regulatory adherence. Optimize platform performance, scalability, and cost-efficiency, leveraging cloud-native technologies and distributed systems. Stay current with ad

About the Team API Frontiers turns OpenAI’s frontier models into production APIs that developers can use to build reliable products and agents. We own the core path connecting models to developers through the Responses API, with a focus on safety, reliability, and speed. Working closely with Research, Safety, Codex, and other API teams, we bring new model capabilities into production and improve them through developer feedback. About the Role We are looking for a backend software engineer to build and operate the services behind the Responses API. You will shape API behavior, bring new capabilities from research into production, and make long-running agent workflows dependable and fast. The work combines distributed systems engineering with product judgment: designing useful developer interfaces, managing staged rollouts, and following production issues through to durable fixes. In this role, you will: Design, build, and operate APIs and backend services that bring frontier model capabilities to developers. Partner with Research, Safety, Codex, and API teams to define API behavior and deliver safe, staged launches. Build API capabilities for agent workflows, including task delegation, context sharing, and parallel execution. Strengthen long-running request reliability across timeouts, cancellation, streaming, and background execution. Improve request-processing performance and tail latency through profiling, efficient systems code, and persistent connections. Turn developer feedback and production failures into better observability, diagnostics, and lasting product improvements. Your background might look something like: 5+ years of experience building and operating backend services or developer-facing APIs in production. Strong software engineering fundamentals, with practical knowledge of distributed systems, concurrency, and asynchronous execution. Ability to diagnose production failures and performance bottlenecks using observability data and profiling. Product

About the Team OpenAI’s Applications Engineering organization builds and operates the products (such as ChatGPT & Codex) that bring our cutting-edge research to millions of users and developers worldwide. The Applied Foundations team owns the core product and platform layers that make those experiences possible — from identity & access, to safety to payments & commerce across all of our apps. Our teams span product engineering, infrastructure, and safety, working together to deliver technology that is reliable, secure, and trusted at global scale. About the Role We’re hiring Full-Stack Software Engineers to design and implement safe services, systems and infrastructure that power our core products. In this role, you will: Architect, build, and improve frontend and backend systems. Work across the full stack to build products and systems from initial exploration through launch readiness. Participate in long-term architectural planning and technical design reviews. Collaborate with cross-functional teams to design solutions that protect against and mitigate adversarial attacks without compromising user experience. You might thrive in this role if you: Have built and shipped full-stack apps or systems end-to-end — in fast-moving, startup-like environments. Have a humble attitude, an eagerness to help your colleagues, and a desire to do whatever it takes to make the team succeed. Enjoy building resilient products and services that handle large scale and complexity. Are self-directed and enjoy figuring out the best way to solve a particular problem Own problems end-to-end, and are willing to pick up whatever knowledge you're missing to get the job done. About OpenAI OpenAI is an AI research and deployment company dedicated to ensuring that general-purpose artificial intelligence benefits all of humanity. We push the boundaries of the capabilities of AI systems and seek to safely deploy them to the world through our products. AI is an extremely powerful tool t

About the Team The Cybersecurity Products team builds products at the frontier of AI and cybersecurity. Our work includes Codex Security and related cyber products that turn advances in model capability into dependable tools for defenders. We help teams find, validate, and remediate vulnerabilities, continuously improve the security of software, and test AI-powered applications before they reach production. About the Role As a Full Stack Software Engineer, you will build the product experiences and systems that make AI-powered security useful in real engineering environments. You will work across web surfaces, APIs, orchestration, data models, and integrations to help security and engineering teams move from a codebase or application to evidence-backed findings, prioritized remediation, and revalidation. You will collaborate closely with product engineers, security researchers, and customer-facing teams. The work spans fast-moving product development and hard systems problems: long-running workflows, large repositories, sensitive data, reliability, observability, and a high bar for earning user trust. This role is based in San Francisco, CA. We use a hybrid work model of 3 days in the office per week and offer relocation assistance to new employees. In this role, you will: Build end-to-end workflows for vulnerability discovery, security scanning, red teaming, findings review, remediation, and reruns. Design and operate backend services for long-running security work, including APIs, asynchronous orchestration, durable state, and integrations with developer workflows. Make complex security results actionable through clear product surfaces, strong evidence, thoughtful prioritization, and reliable reporting. Partner with security researchers, product teams, and users to evaluate quality, reduce noise, improve coverage, and ship safely. You might thrive in this role if you: Have experience shipping production full-stack products across modern web frontends and backend s

About the Team The Monetization team is a new cross-functional group working across engineering, product, research, and design to build the foundational systems that will help OpenAI scale access to intelligence responsibly. Our mission is to develop user-first, privacy-preserving monetization products—including next-generation ads experiences—that strengthen user trust, unlock economic opportunity, and support OpenAI’s long-term innovation. Monetization plays a critical role in enabling OpenAI to continue pushing the boundaries of AI capabilities while ensuring the benefits of AGI are broadly shared. We believe monetization must be aligned with user value, uphold rigorous privacy and safety standards, and sustain a healthy ecosystem of developers and businesses. This team operates in a greenfield environment and moves quickly through prototyping, experimentation, and iterative deployment. We partner closely with Product, Design, and Research to bring research breakthroughs into real-world systems at global scale. About the Role We’re looking for an experienced Software Engineer to help build the core infrastructure behind OpenAI’s monetization and ads systems. In this foundational role, you’ll architect and implement distributed systems that power OpenAI’s monetization stack—focusing on reliability, performance, privacy, and large-scale operation. You’ll work across backend, systems, and platform layers to define and implement 0→1 infrastructure, partnering closely with Product, Design, and Research to shape the future of monetized AI experiences. Your work will enable both internal and external teams to build on safe, scalable, and robust monetization primitives. This role is exclusively based across our San Francisco & Seattles sites. We offer relocation assistance to new employees. In this role, you will: Design and build the foundational backend and infrastructure powering OpenAI’s monetization and ads systems Architect large-scale distributed systems that

Every day, tens of millions of people come to Roblox to explore, create, play, learn, and connect with friends in 3D immersive digital experiences– all created by our global community of developers and creators. At Roblox, we’re building the tools and platform that empower our community to bring any experience that they can imagine to life. Our vision is to reimagine the way people come together, from anywhere in the world, and on any device. We’re on a mission to connect a billion people with optimism and civility, and looking for amazing talent to help us get there. A career at Roblox means you’ll be working to shape the future of human interaction, solving unique technical challenges at scale, and helping to create safer, more civil shared experiences for everyone. The Data Access team within Infra / Storage builds EaaS (Entities-as-a-Service), Roblox’s large-scale managed OLTP access and management platform powering tens of millions of QPS across thousands of services. EaaS abstracts the complexity of distributed databases and caching systems behind a consistent and productive developer experience, enabling teams across Roblox to safely build and operate stateful systems at massive scale without requiring deep database expertise. The team operates at the intersection of distributed systems engineering, reliability engineering, and platform architecture — solving hard infrastructure problems that directly impact Roblox-wide scale and stability. As a Senior Software Engineer you will work on some of Roblox’s hardest backend infrastructure challenges around scalability, reliability, workload governance, adaptive flow control, and distributed systems. You Will Build and evolve EaaS, Roblox’s managed OLTP access platform powering tens of millions of QPS across hundreds of services. Design infrastructure that abstracts distributed databases and caching systems behind a consistent, safe, and highly productive developer experience. Drive reliability and scal

Replit is the agentic software creation platform that enables anyone to build applications using natural language. With millions of users worldwide, Replit is democratizing software development by removing traditional barriers to application creation. About Replit Replit is building the world’s most ubiquitous AI coding agent. Replit Agent can be used by anybody to bring their ideas to life. Whether it’s an app for yourself, the next great startup idea, or a tool to make you more productive at work, Replit Agent can help build it. Replit is also the leader in secure vibe coding. We protect apps, give users features to manage security risks, and help them vibe code more safely. About the Role In this role you will build powerful tools that help product engineers iterate rapidly on the Agent experience and directly enhance the core Agent itself. You’ll bridge the gap between the AI team (working on the core Agent logic) and the UX team (crafting delightful Agent experiences), enabling both groups to excel within their specialties. This role blends systems engineering, developer experience and product engineering. We tackle complex challenges across the full stack, from browser-based interfaces to high-performance backends to Linux systems engineering. We’re looking for engineers who have a keen sense of the product experience and how to power it with performant systems. On this team, you’ll have the opportunity to grow your skills across our infrastructure and product, and to lead end-to-end efforts with meaningful impact. We value diverse perspectives and encourage candidates from all backgrounds and experiences to apply. You Will Build high-throughput backend applications and services, like streaming chat between user and agent. Design a collaborative "Multiplayer Computer" that lets humans and AI agents work together on shared shells, filesystems, and state—conflict-free and in real time. Develop infrastructure (frontend & backend) that empowers product enginee

About the Team OpenAI’s Applications Engineering organization builds and operates the products (such as ChatGPT & Codex) that bring our cutting-edge research to millions of users and developers worldwide. The Applied Foundations team owns the core product and platform layers that make those experiences possible — from identity & access, to safety to payments & commerce across all of our apps. Our teams span product engineering, infrastructure, and safety, working together to deliver technology that is reliable, secure, and trusted at global scale. About the Role We’re hiring Backend Software Engineers to design and implement safe services and infrastructure that power our core products. What You’ll Do Architect, build, and improve scalable backend systems and APIs. Drive performance, reliability, and safety across distributed services. Implement data storage, retrieval, compute, and integration solutions. Participate in long-term architectural planning and technical design reviews. Collaborate with cross-functional teams to design solutions that protect against and mitigate adversarial attacks without compromising user experience. You Might Thrive Here If You: Have strong experience with distributed systems, APIs, and backend languages (e.g., Go, Python, Rust, C++). Have experience setting up and maintaining production backend services and data pipelines. Have a humble attitude, an eagerness to help your colleagues, and a desire to do whatever it takes to make the team succeed. Enjoy building resilient services that handle large scale and complexity. Are self-directed and enjoy figuring out the best way to solve a particular problem Own problems end-to-end, and are willing to pick up whatever knowledge you're missing to get the job done. About OpenAI OpenAI is an AI research and deployment company dedicated to ensuring that general-purpose artificial intelligence benefits all of humanity. We push the boundaries of the capabilities of AI systems and seek

About the Team The Support Automation team at OpenAI scales the organization by applying cutting-edge AI models to real-world challenges, automating and enhancing work across the organization. From customer operations to engineering, we develop an ecosystem of automation products that empower our colleagues and drive impact. We're passionate about crafting products that serve those around us, blending rapid prototyping with a focus on long-term quality and reliability. By creating reusable solutions, we create patterns that can be applied across diverse domains within OpenAI. TLDR: this team leverages OpenAI technology to improve OpenAI, and you’ll have the opportunity to leverage the full extent of our tech (both public and pre-released) to accomplish this mission. About the Role We’re looking for a Backend Software Engineer with experience working in ML/LLM-heavy domains to help to design and build an evals infrastructure that measures the quality of OpenAI’s support automation. This is a deeply technical and highly cross-functional role where you’ll build robust systems and backend services that serve as the foundation for how knowledge is created, accessed, and applied across OpenAI. The role will especially focus on working closely with Data Science and Research partners to design and build evals at scale. In this role, you will: Design eval pipelines that are reliable, reproducible, and extendable Build the infrastructure for continuous eval monitoring frameworks (regression/drift monitoring, building robust golden datasets) along with feedback loops that ultimately strengthen support automation Design, build, and maintain backend services and APIs to support intelligent automation and knowledge systems Integrate and structure data across internal platforms, transforming it into formats optimized for use by downstream systems and AI workflows. Collaborate closely with data, research, and engineering teams to integrate OpenAI models into high-leverage workflows

About Us: Blockworks is an information platform that sits at the center of the crypto industry. We transform raw, complex data and facts into actionable research, trusted alpha-driven insights, and world-class events. The result is transparency and confidence. Blockworks connects investors and businesses in onchain capital markets. We give businesses a platform to earn trust and provide investors with the information they need to underwrite the asset class. Who You Are: You have a keen focus on backend and API development and Software engineering is your passion. You are a player-coach and a natural leader who understands the technical and human elements that go into great software design. You have a results-oriented attitude and a passion for delivering flawless releases and developing digital product pipelines (CI/CD pipelines). You have a proven track record facilitating engineering teams to increase productivity and quality. You're excited at the possibility of being on the ground floor of the design and development of backend strategies. You bring a passion for designing and maintaining scalable API services that handle large amounts of data elegantly. You love moving quickly in a fast-paced start-up, but you also bring intentionality, sustainability and scalability to your approach as an engineer. What You’ll Do: As a Senior Backend Engineer at Blockworks, you’ll design, build, and maintain the systems that power our products end-to-end. From high-performance APIs to database architecture, you’ll own the backend layer that makes everything else possible. You won’t just be handed requirements, you’ll help define them, scope projects, and make the architectural decisions that shape our technical foundation. Your work will directly impact our research platform ( blockworksresearch.com ) and our media site ( blockworks.co ; 1M+ monthly active users). Every day will look a little different, but in general, you will do things like: Architect, build, and ship backend

Every day, tens of millions of people come to Roblox to explore, create, play, learn, and connect with friends in 3D immersive digital experiences– all created by our global community of developers and creators. At Roblox, we’re building the tools and platform that empower our community to bring any experience that they can imagine to life. Our vision is to reimagine the way people come together, from anywhere in the world, and on any device. We’re on a mission to connect a billion people with optimism and civility, and looking for amazing talent to help us get there. A career at Roblox means you’ll be working to shape the future of human interaction, solving unique technical challenges at scale, and helping to create safer, more civil shared experiences for everyone. As a Senior Backend Engineer on the User Communities team, you’ll own the backend systems that power social engagement features (Announcements, Forums, Polls, Roles & Permissions systems) for millions of players and creators on Roblox. Your day-to-day will focus on building and scaling the infrastructure that makes both in-experience and on-platform communication and player engagement fast, safe, and reliable. That means driving architectural decisions, reasoning through trade-offs, influencing stakeholders, championing user-first safety standards, and defining developer-facing APIs so creators can build richer experiences. You'll work closely with frontend and backend engineers, product, design, and data scientists across teams, and you'll have real influence over our technical and product direction. If you're an experienced engineer who gets excited about large-scale distributed systems and wants to shape the way millions of people connect inside virtual worlds, we'd love to talk. You Will: Shape the backend engineering culture across the Communities team. Your influence extends beyond your immediate pod to improve how we build, review, and ship software across the entire org. Act as

At Snowflake, we are powering the era of the agentic enterprise. To usher in this new era, we seek AI-native thinkers across every function who are energized by the opportunity to reinvent how they work. You don’t just use tools; you possess an innate curiosity, treating AI as a high-trust collaborator that is core to how you solve problems and accelerate your impact. We look for low-ego individuals who thrive in dynamic and fast-moving environments and move with an experimental mindset — who rapidly test emerging capabilities to discover simpler, more powerful ways to deliver results. At Snowflake, your role isn't just to execute a function, but to help redefine the future of how work gets done. About the team The Apps & Experiences Platform team powers the systems and services behind all of our user-facing applications, including Snowsight, Snowflake Intelligence, and new mobile experiences. Our mission is to build innovative backend services, developer tooling, platform infrastructure, and AI-powered capabilities that enable exceptional product experiences at scale. As part of our team, you’ll work across feature development, platform engineering, infrastructure, and internal tooling to support both end users and developers. We care deeply about building systems that are reliable, scalable, maintainable, and performant. Snowflake is a high-growth AI Data Cloud company, and we’re looking for exceptional engineers to help us scale the next generation of our platform. A key part of this is our work on our internal AI developer agent, which is designed to fundamentally democratize end-to-end web app development across all engineering teams by translating product specs and designs into a fully functional, production-ready features. AS A SENIOR SOFTWARE ENGINEER FOR THE APPS & EXPERIENCES PLATFORM TEAM, YOU WILL: Design, build, and operate scalable backend services and platform infrastructure that power Snowflake’s user-facing applications. Contribute across th

At Snowflake, we are powering the era of the agentic enterprise. To usher in this new era, we seek AI-native thinkers across every function who are energized by the opportunity to reinvent how they work. You don’t just use tools; you possess an innate curiosity, treating AI as a high-trust collaborator that is core to how you solve problems and accelerate your impact. We look for low-ego individuals who thrive in dynamic and fast-moving environments and move with an experimental mindset — who rapidly test emerging capabilities to discover simpler, more powerful ways to deliver results. At Snowflake, your role isn't just to execute a function, but to help redefine the future of how work gets done. About the team The Apps & Experiences Platform team powers the systems and services behind all of our user-facing applications, including Snowsight, Snowflake Intelligence, and new mobile experiences. Our mission is to build innovative backend services, developer tooling, platform infrastructure, and AI-powered capabilities that enable exceptional product experiences at scale. As part of our team, you’ll work across feature development, platform engineering, infrastructure, and internal tooling to support both end users and developers. We care deeply about building systems that are reliable, scalable, maintainable, and performant. Snowflake is a high-growth AI Data Cloud company, and we’re looking for exceptional engineers to help us scale the next generation of our platform. A key part of this is our work on our internal AI developer agent, which is designed to democratize end-to-end app development across all engineering teams by translating product specs and designs into fully functional, production-ready features. AS A SENIOR SOFTWARE ENGINEER FOR THE APPS & EXPERIENCES PLATFORM TEAM, YOU WILL: Design, build, and operate scalable backend services and platform infrastructure that power Snowflake’s user-facing applications. Contribute across the full development l

At Playlist, life's richest moments happen when people step away from screens to move, connect, explore, and play. We're building the definitive platform for intentional living, connecting people with inspiring experiences in fitness, wellness, and beyond. With popular brands like Mindbody and ClassPass, Playlist empowers businesses and individuals, making it effortless for aspirations to become actions. Join us in reshaping technology's role to foster meaningful, real-world connections. Mindbody equips wellness entrepreneurs with technology to support thriving businesses and create exceptional experiences. Innovation and curiosity drive our culture, connecting businesses and individuals through cutting-edge solutions. Join us if you're passionate about enhancing wellness through technology. The Role You'll Play: Build and maintain performant backend systems and applications that drive real-world experiences Partner with Product, Design, and QA to bring features to life from ideation through deployment, always iterating with the end-user in mind. Champion engineering best practices—automated testing, peer reviews, observability, and elegant design Lead and influence architecture decisions that prioritize scalability and simplicity <span data-contrast=&quo