Backend Developer Intern Jobs

Who we are About Stripe Stripe is a financial infrastructure platform for businesses. Millions of companies—from the world's largest enterprises to the most ambitious startups—use Stripe to accept payments, grow their revenue, and accelerate new business opportunities. Our mission is to increase the GDP of the internet, and we have a staggering amount of work ahead. That means you have an unprecedented opportunity to put the global economy within everyone's reach while doing the most important work of your career. About the team The Global Payments Experiences group is an organization focused on bringing new and novel payment methods to Stripe, and ensuring Stripe's systems work well for merchants globally. This team works with internal and external partners to expand regional, non-card payment options, and to expand the use of Stripe's payments processing globally. What you'll do This is a São Paulo-based team, with platform teams in the US and Europe and sister teams worldwide. This team in particular will build and maintain new payment methods for Stripe, with a focus on LATAM and North America. They will manage local market idiosyncrasies, become regional experts that other Stripe teams will rely on, and partner with many non-tech functions at Stripe to expand our global reach and product portfolio. Responsibilities Design and reason about integration experiences with a strong focus on end-user simplicity and developer experience Build back-end services and integrations across Stripe's payments product Engage and interact with external partners to determine and build technical solutions Engage directly with users to understand their business needs and translate requirements into concrete solutions

About the Role: As a Senior Software Engineer at K Health, you are the champion of technical excellence for a high-stakes portfolio of clinical AI and a suite of products that serve the patients and the physicians. We don't just build apps; we build, and operate modern, AI-powered, 24/7 virtual clinics for the nation’s largest health systems. In this role, your mission is to architect a product ecosystem where reliability, privacy, and performance are non-negotiable. You will lead the development of reusable components and resilient architectures that exude trust, ensuring that every patient interaction is seamless and every clinical data point is secure. You will be a "multiplier," creating the foundational frameworks that allow us to deploy 5-star experiences across a portfolio of partners without sacrificing the quality our users depend on. This role requires onsite presence in our New York City office 4 days a week and does not provide immigration support. What you will do: Architect for Trust: Design and drive a unified product engineering strategy that supports a portfolio of products and solutions, prioritizing modularity, reusability, and extreme resiliency. Full-Stack Ownership: Own the end-to-end lifecycle of products and features, from multi-platform clients, to the Kotlin/JVM-based backend services that power them. Quality as a Feature: Define and enforce standards for high-stakes engineering—ensuring that performance, accessibility, and data privacy are baked into the architecture, not added as afterthoughts. Platform Innovation: Proactively modernize our systems to leverage agentic AI tools that improve developer productivity and team efficiency. Platform Evolution: Build and maintain the shared libraries and DSLs that enable rapid, high-quality deployments for our health system partners. Technical Stewardship: Act as a stabilizing force in complex technical situations, bringing clarity to ambiguous requirements and making informed decisions 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. Discovery UX sits at the intersection of product innovation and high-scale infrastructure. Every Roblox user starts their journey on the homepage, and every Roblox developer needs to find their correct audience. Our team works closely with product and engineering teams across Roblox to bridge this gap by improving the user journey from landing on Roblox to joining an experience. We primarily work on Home, Search, Charts, and Experience Details pages, for both the Roblox website and app. As a Principal Software Engineer , you will craft robust, extensible systems for high-traffic surfaces. While you are a frontend expert at heart, you are a versatile engineer who isn't afraid to dive into the backend or data pipelines to ship a complete feature. You will drive solutions using React and modern technologies, helping us build efficiently across devices. If you have a deep understanding of frontend architecture and a genuine curiosity for diving into data to understand "the why" behind an experiment, you will be right at home with us. This role reports to the Engineering Manager on the Discovery UX team. You Will: Design, build, and ship features that define the discovery journey for millions of

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 Software Engineer on the Communications team, you will work on real-time communication across 2D and 3D spaces for billions of users while keeping interactions civil, safe, and expressive. Communication is at the core of what makes Roblox a vibrant social platform, the systems you build will define how tens of millions of people connect every day. You will work with teams across Game Engine, Safety, and ML Platform, building backend services at scale, data pipelines, and ML models that strengthen the underlying chat and policy infrastructure. You will build and ship detection systems that identify chat violations and continuously evolve to outpace bad actors circumventing our safety policies. As a core contributor to a broader suite of communication products, you will drive feature development while embedding safety into the foundation of the platform. If you are a developer with an understanding of large scale systems and want to shape how the next generation of Roblox users interact safely in the metaverse, you’ll be right at home within our highly-skilled and rapidly growing team. You will: Engineer and scale the communication infrastructure that supports millions of c

About Anyscale: At Anyscale , we're on a mission to democratize distributed computing and make it accessible to software developers of all skill levels. We’re commercializing Ray , a popular open-source project that's creating an ecosystem of libraries for scalable machine learning. Companies like OpenAI , Uber , Spotify , Instacart , Cruise , and many more, have Ray in their tech stacks to accelerate the progress of AI applications out into the real world. With Anyscale, we’re building the best place to run Ray, so that any developer or data scientist can scale an ML application from their laptop to the cluster without needing to be a distributed systems expert. Proud to be backed by Andreessen Horowitz, NEA, and Addition with $250+ million raised to date. About the role: Ray aims to provide a universal API for building distributed applications (e.g. a machine learning pipeline of feature engineering, model training, and evaluation). Data is usually a core element connecting these different stages, and therefore plays a critical role in Ray’s usability, performance, and stability. We are looking for strong engineers to build, optimize, and scale Ray’s Datasets library and data processing capabilities in general. About the Ray Data team: The Ray Data team currently develops and maintains the Ray Datasets library, which is already powering critical production use cases (e.g. large scale data compaction at Amazon , and ML pipeline at Alibaba ). Ray Datasets is a Python library built on top of Apache Arrow and Ray Core (Ray’s C++ backend), and the Ray Data team interacts closely with Ray Core components including the scheduler and the memory & I/O subsystems. The Ray Data team also works closely with Ray’s ML libraries including Train, RLlib, and Serve. A snapshot of projects you will work on: - Performance of Ray Datasets at large scale (leveraging Arrow primitives, optimizing Ray object manager, etc.) - Integration with ML training and data sources - Stability an

Who we are At Twilio, we’re shaping the future of communications, all from the comfort of our homes. We deliver innovative solutions to hundreds of thousands of businesses and empower millions of developers worldwide to craft personalized customer experiences. Our dedication to remote-first work , and strong culture of connection and global inclusion means that no matter your location, you’re part of a vibrant team with diverse experiences making a global impact each day. As we continue to revolutionize how the world interacts, we’re acquiring new skills and experiences that make work feel truly rewarding. Your career at Twilio is in your hands. . Hiring and how we work We use Artificial Intelligence (AI) to help make our hiring process efficient. That said, every hiring decision is made by real Twilions! Also, while we are a remote-first company, you may be asked to report in person on an ad-hoc basis for team gatherings, functional off-sites or customer meetings. . See yourself at Twilio Join the team as a Senior Software Engineer for Stytch, where you'll shape the next generation of identity products. About the job As a Senior Software Engineer you will help scale Stytch’s core product as we bring Stytch capabilities to Twilio’s full customer base, delivering secure, developer-first identity experiences. You’ll build backend APIs that power authentication, authorization, and emerging agentic and non-human identity use cases. You’ll partner closely with product and engineering leadership to design and deliver high-impact customer-facing features, and evolve our platform for Twilio’s scale. This is a rare chance to operate like a startup within Twilio: you’ll work in a high-ownership environment with startup speed, backed by Twilio’s reach and scale. Responsibilities Build and own backend product capabilities for Stytch’s identity platform on Twilio—shipping new API surfaces and core authentication flows, including agentic and non-huma

About the Team With Codex we’re building an AI software engineer. One that you can pair with, delegate to, or even ask to take on future tasks proactively. Our team is a fast-moving group within OpenAI, bringing together research, engineering, design, and product. We iteratively build the Codex agent harness and product to get the most out of the model, and we iteratively train the model to be great at complex software engineering tasks. The Codex team is responsible for building state-of-the-art AI systems that can write code, reason about software, and act as intelligent agents for developers and non-developers alike. We operate across research, engineering, product, and infrastructure; owning the full lifecycle of experimentation, deployment, and iteration on novel coding capabilities. Codex Enterprise builds the ecosystem, governance, and enterprise capabilities that help Codex spread across developers, teams, and organizations worldwide. The Enterprise Controls team owns the systems that allow companies to safely deploy Codex across their organization while protecting their most sensitive code, data, and internal knowledge. About the Role As Codex adoption grows inside large organizations, customers are increasingly trusting Codex with their most valuable assets: proprietary codebases, internal documentation, customer data, and sensitive workflows. This role will help build the enterprise control plane that makes Codex secure, governable, and trustworthy at scale. You will design and operate backend systems that give enterprise administrators visibility and control over how Codex is used across their organization. You will work across identity, access, encryption, policy enforcement, auditability, and admin controls. This may include systems that let customers manage encryption keys, control which Codex capabilities are enabled, enforce organizational policies, and understand how data flows through Codex. This role owns systems end-to-end: from architecture and

About Anthropic Anthropic’s mission is to create reliable, interpretable, and steerable AI systems. We want AI to be safe and beneficial for our users and for society as a whole. Our team is a quickly growing group of committed researchers, engineers, policy experts, and business leaders working together to build beneficial AI systems. About the role The Safeguards team is responsible for ensuring our models and products are developed and deployed safely. We're looking for engineers for our Review Tooling team, which builds the systems that humans — and increasingly Claude — use to investigate potential harms and take enforcement actions across Anthropic's first-party products and third-party cloud platforms. You'll own the tools our safety investigators rely on to understand what's happening on our platforms and act on it, as well as the platform underneath those tools. That platform includes data analysis capabilities, privacy-preserving primitives that keep review workflows compatible with our data retention commitments, and a sandbox environment where new review interfaces and workflows can be built and iterated quickly. These are internal tools, but they are anything but low-stakes: the speed, clarity, and reliability of this tooling directly determines how quickly Anthropic can identify harmful behavior, make sound enforcement decisions, and feed signals back into model training and safety classifiers. You'll partner closely with policy, operations, data science, legal, and privacy teams to ensure our enforcement systems are effective, accurate, and trustworthy. Key responsibilities Build investigation, review, and enforcement tooling for both first-party and third-party platform surfaces — including case queues, investigation views, decision and audit logging, and account-actioning workflows Develop the platform layer of reusable APIs, data storage, and backend services that lets new review workflows be stood up quickly and safely Stand up and run deployments

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 platforms in our Engineering Acceleration org dictate how thousands of Roblox engineers ship, and how every backend service gets built, deployed, and kept reliable at scale. They sit on the critical path for production reliability, developer velocity, and security posture. Reporting to Andrew Swerdlow, you will rethink the entire engineering toolchain from the ground up to be agentic-native, creating a world where AI agents are first-class participants in software development and humans set direction and supervise. This is a unique opportunity to define what modern engineering infrastructure looks like at one of the largest platforms in the world. You will: Reimagine the engineering toolchain as agentic-native, designing the platforms, guardrails, and feedback loops that let AI agents safely drive migrations, validation, and routine operational work. Set a bold technical direction for AI-driven quality, including agent-generated tests, automated coverage of untested paths, intelligent verification, and continuous-deployment workflows. Make software quality and SEV prevention a measurable property of the platform by investing in safe-change mechanisms, automated verification, progressive

ABOUT BASETEN Baseten powers mission-critical inference for the world's most dynamic AI companies, like Cursor, Notion, OpenEvidence, Abridge, Clay, Gamma, and Writer. By uniting applied AI research, flexible infrastructure, and seamless developer tooling, we enable companies operating at the frontier of AI to bring cutting-edge models into production. We're growing quickly and recently raised our $1.5B Series F , led by Altimeter Capital, Conviction Partners, and Spark Capital. Join us and help build the platform engineers turn to ship AI products. THE ROLE We’re looking for a seasoned Frontend Engineer to craft performant and delightful user experiences across Baseten’s core platform. You’ll own critical parts of our web application stack and collaborate cross-functionally with product, design, and backend teams to launch impactful features that help users deploy and manage AI systems at scale. EXAMPLE INITIATIVES Rolling Deployments Model APIs for frontier models Model training built for production inference RESPONSIBILITIES Design, implement, and maintain responsive, accessible, and user-friendly frontend interfaces using React and TypeScript Collaborate closely with product designers to turn complex ideas into elegant, intuitive UIs Optimize application performance and reliability, with a focus on rendering speed and responsiveness Drive major frontend initiatives, including partnering with backend teams to define APIs and test and refine end-to-end flows Establish best practices, and mentor other engineers on frontend technologies Build reusable component libraries and frontend infrastructure that accelerate product development Partner with backend and platform teams to define and refine APIs and end-to-end flows REQUIREMENTS 5+ years of experience building production-grade web applications Deep expertise in React, TypeScript, and modern web development tooling Track record of building well-crafted, performant, and scalable UIs Strong product intuition and emp

Who we are About Stripe Stripe is a financial infrastructure platform for businesses. Millions of companies—from the world's largest enterprises to the most ambitious startups—use Stripe to accept payments, grow their revenue, and accelerate new business opportunities. Our mission is to increase the GDP of the internet, and we have a staggering amount of work ahead. That means you have an unprecedented opportunity to put the global economy within everyone's reach while doing the most important work of your career. About the team The Global Payments Experiences group is an organization focused on bringing new and novel payment methods to Stripe, and ensuring Stripe's systems work well for merchants globally. This team works with internal and external partners to expand regional, non-card payment options, and to expand the use of Stripe's payments processing globally. What you'll do This is a São Paulo-based team, with platform teams in the US and Europe and sister teams worldwide. This team in particular will build and maintain new payment methods for Stripe, with a focus on LATAM and North America. They will manage local market idiosyncrasies, become regional experts that other Stripe teams will rely on, and partner with many non-tech functions at Stripe to expand our global reach and product portfolio. Responsibilities Design and reason about integration experiences with a strong focus on end-user simplicity and developer experience Build back-end services and integrations across Stripe's payments product Engage and interact with external partners to determine and build technical solutions Engage directly with users to understand their business needs and translate requirements into concrete solutions Collaborate with cross-functional teams including product, partnerships, eng platforms, and other engineering teams to deliver these solutions Contribute to software platforms used across payments at Stripe Who you are We're looking for someone who meets the minimum re

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 Software Engineer on our Release Engineering team, you will build the systems that hundreds of engineers across Roblox use every day to safely ship code to tens of millions of concurrent players. Your work will empower teams to ship bold, high-impact changes quickly and confidently on every device Roblox runs on. If you enjoy building developer-facing infrastructure where reliability and blast radius directly impact end-users, you will be right at home on our growing team. You Will: Design and develop backend services and automation that power our release and experimentation process across desktop, mobile, console, VR, and servers Work in C++ engine code to improve telemetry reporting, enhance feature rollout and automatic abort capabilities, and extend release functionality Build progressive client and server rollout, regression detection, and automated rollback systems that keep our weekly multi-platform releases safe at scale Work directly with engineering customers to turn pain points into durable, flexible, and safe-by-default tooling You Have: 5+ years building backend services with C#, Python, TypeScript, or similar Familiar with and comfortable working with C++ Familiar

About Anyscale: At Anyscale , we're on a mission to democratize distributed computing and make it accessible to software developers of all skill levels. We’re commercializing Ray , a popular open-source project that's creating an ecosystem of libraries for scalable machine learning. Companies like OpenAI , Uber , Spotify , Instacart , Cruise , and many more, have Ray in their tech stacks to accelerate the progress of AI applications out into the real world. With Anyscale, we’re building the best place to run Ray, so that any developer or data scientist can scale an ML application from their laptop to the cluster without needing to be a distributed systems expert. Proud to be backed by Andreessen Horowitz, NEA, and Addition with $250+ million raised to date. About the role Ray aims to provide a universal API for building distributed applications. To achieve this goal requires a distributed system with high levels of performance and reliability. We're looking for engineers with systems software experience that are interested in contributing to the Ray backend. About the Ray Core Team The Ray Core team develops and maintains the Ray C++ backend (e.g., distributed scheduler, language runtime integration, I/O and memory subsystems). We are responsible for the reliability, scalability, and performance of Ray as well as ensuring that Ray provides the right feature set to support higher level libraries and use cases. The team works on a balance of new features / distributed libraries, test infra improvements, debugging, and longer-term architectural improvements to Ray. A snapshot of projects you can work on: Optimizing performance of large-scale workloads on Ray Stability and stress testing infrastructure Improving fault tolerance (HA) As part of this role, you will: Leading cross-team projects while mentoring junior team members Develop high quality open source software to simplify distributed programming (Ray) Identify, implement, and evaluate architectural improvements

Senior Fullstack Software Engineer Location: Soho, NYC / Hybrid (an in-person interview may be required) Department: Engineering The Role We’re looking for a Senior Fullstack Software Engineer to help architect, build, and scale the next generation of our Flowcode 2 platform and consumer experiences. You will join our engineering team with a focus on creating amazing end user hub and landing page experiences that are dynamic and engaging, as well as the platform and management capabilities for creators on the platform. You’ll work across the stack — from contributing to backend services to building out dynamic end to end landing pages. Though this is a full stack position, we are looking for someone that has deep backend experience as well. As one of the senior engineers on a small but highly capable team, you’ll own medium to large sized features, drive technical execution, contribute to a delivery focused environment, and mentor others. You’ll balance hands-on engineering with architectural thinking, helping us move fast while maintaining reliability, performance, and code quality. This is an ideal role for a problem-solver who values simplicity over complexity, enjoys building dynamic and interactive applications and approaches engineering with pragmatism and curiosity. What You’ll Do Design, build, and maintain scalable features across a modern front-end framework and backend services. With support, own key features end-to-end, from data design to user-facing experiences. Architect for growth — help drive your pods’s technical roadmap and shepherd established engineering best practices. Collaborate across teams with product, design, and data to deliver measure, deliver and grows features quickly and iteratively. Write clean, reliable, and maintainable code, with strong attention to performance, best practices and developer experience. Mentor engineers and help elevate technical execution across you pod. Stay pragmatic — balance ideal engineering with the

Lithic is the modern card issuing and processing platform empowering ambitious financial companies to build the future of payments. Our infrastructure powers card programs for 100+ innovative clients, from fintechs reimagining credit and digital banking to platforms transforming disbursements and spend management. Companies like Mercury, Flex, and Novo rely on Lithic's developer-friendly APIs, direct network connections, and flawless reconciliation to launch and scale card programs in weeks, not years. We're building a future where access to better financial products materially improves people's lives, free from the constraints of 30-year-old mainframes and legacy processors. We're proud to be backed by world-class investors who share that vision, including Bessemer Venture Partners, Index Ventures, Spark Capital, Stripes, and Mastercard, along with many others. We're a team of 170+ across 26 states and 7 countries, headquartered in New York City. We are hiring for our Treasury team Software Engineers at various levels (II and Senior) who are curious and willing to dive deep and understand our technology and domain in order to solve interesting and hard problems.The Treasury team maintains and builds the backend services that manage the flow of funds between Lithic and third parties. This includes our ledger, ACH and wire infrastructure, and associated reconciliation. The systems we maintain have high standards of reliability and correctness. You will become an expert in the card payments space. The Treasury team primarily uses Python for their tech stack. What You'll Do: Ensure high reliability and correctness for Lithic’s ledger and orchestrated funds flows Develop new features to better serve Lithic customers Ensure that the team is delivering reliable, secure, and scalable code with minimal tech debt Own initiatives from planning to launch, keeping stakeholders informed and aligned along the way Lead efforts to improve systems and processes wit