Jobs in United States

Senior Software Development Engineer L3 in United States

1,941 active opportunities · Updated October 2026

Explore current senior software development engineer l3 jobs across United States. Filter by work mode, employment type, experience, department, date posted and distance.

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📍 San Mateo, CA, United States· Full-time
✓ High-confidence listingCompany trend -100%

From $196.8K/yr

Quick readStrong listing-quality and freshness signals

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 an Economy Fraud engineer, you defend Roblox from all types of fraud, including theft, scams, money laundering, and payment fraud. Roblox is a high-growth, unique product environment. You will be developing anti-fraud and abuse solutions for web, mobile, and 3D environments. This high impact work and your innovation is critical for the well-being of our community and to the future of our company. We aim for our users to have peace of mind that their communities and transactions are protected. Our defenses also protect our company’s rapid expansion and safeguard billions in revenue. Roblox’s virtual marketplace handles over 4 million transactions a day, and enables our top developers to make millions of dollars a year. Our team’s challenges are not just regular day-to-day technical challenges. Fraud and abuse approaches need to shift over time, depending on the current behaviors of fraudsters. As an Economy Fraud engineer, you will be in a data-driven environment developing both classical and novel approaches to detect and prevent this bad behavior. You Have: 4+ years of professional experience working with scalable, distributed systems Strong experience in large-scale, data-driven

SQLAWSGitMachine Learning
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📍 San Mateo, CA, United States· Full-time
✓ High-confidence listingCompany trend -100%

From $243.3K/yr

Quick readStrong listing-quality and freshness signals

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

TypeScriptPythonAWSGit
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📍 San Mateo, CA, United States· Full-time
✓ High-confidence listingCompany trend -100%

From $196.8K/yr

Quick readStrong listing-quality and freshness signals

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 the Cell Platform team at Roblox, you will build systems that Roblox engineers use to create and deploy resources onto Kubernetes. Our engineers deploy their services in a complex, hybrid, multiple-cluster, K8s environment. The Cell Platform manages this complexity for our users, with tools, APIs, K8s controllers, and UX, simplifying infrastructure for our internal customers. You Have: A desire to work on critical, large-scale distributed systems An appreciation of observability and instrumentation and tooling to make your life easier 3+ years of experience as software engineer Bachelor's degree in Computer Science or an equivalent field You will: Build our Roblox-wide control plane using Kubernetes primitives (and plenty of custom resources) Work on the interface of the few hundred person infrastructure organization to the thousands of Roblox engineers Write and review high quality code and tests (largely Golang) Work on a team that cares about inclusivity and shipping For roles that are based at our headquarters in San Mateo, CA: The starting base pay for this position is as shown below. The actual base pay is dependent upon a variety of job-related

AWSKubernetesGitAI
R
📍 San Mateo, CA, United States· Full-time
✓ High-confidence listingCompany trend -100%

From $243.3K/yr

Quick readStrong listing-quality and freshness signals

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 the Communications team, you'll own the backend systems that power chat and messaging for millions of players on Roblox and support billions of messages per day. Your day-to-day will focus on building and scaling the infrastructure that makes in-game communication fast, safe, and reliable. That means driving architectural decisions, creating communication modes that don't exist yet, and defining developer-facing APIs so creators can build richer experiences. You'll work closely with frontend engineers, platform, product, and design, and you'll have real influence over the technical and product direction of the team. 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 Build and scale backend infrastructure for millions of concurrent users, architecting high-throughput distributed services, integrating ML models, and enabling rapid product experimentation Equip creators with the APIs and tools to build deeply integrated social experiences in their games Own projects end-to-end: from design and architecture through produc

SQLPostgreSQLMySQLAWS
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📍 San Mateo, CA, United States· Full-time
✓ High-confidence listingCompany trend -100%

From $243.3K/yr

Quick readStrong listing-quality and freshness signals

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 Ads User Experience team at Roblox is dedicated to developing cutting-edge software and integrations that facilitate ads on Roblox. Our focus lies in building a first-of-its-kind ads system in our Game Engine. We are developing different ad formats and integrations, starting with video. We are looking for a Senior Software Engineer with an expertise in C++. This is a high-impact position. Ads at Roblox is at the beginning of our journey, presenting an amazing opportunity to get in at the ground floor and help build a multi-billion dollar business from scratch. We are approaching this challenge with a strong focus on performance and a deep respect for our community — ensuring everyone continues to have an exceptional experience on Roblox. As we move toward enabling cooperative experiences for an infinite number of players in infinitely scalable worlds, we are looking for a Senior Engineer who is both technically exceptional and capable of delivering meaningful, real-world impact. You Will: Help build a first-of-its-kind ads system within the Roblox Game Engine Develop new ad formats and integrations, starting with video Contribute to the design and performance of systems that

AWSGitAIC++
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📍 San Mateo, CA, United States· Full-time
✓ High-confidence listingCompany trend -100%

From $243.3K/yr

Quick readStrong listing-quality and freshness signals

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. Roblox's data infrastructure processes petabytes of data daily, powering analytics, ML, and product decisions. As a Senior Software Engineer in our Data Infra org, you will design, build, and scale the distributed data infrastructure platforms that power Roblox. You will own and drive the next-generation architecture of our core platforms, which span Kafka, Flink, Spark, Trino, Druid, Airflow and Data Catalog. This role combines high ambiguity and ownership to push the boundaries of what our infrastructure can handle at massive scale, giving you the unique opportunity to steer the evolution of the data landscape. You Will: Own and Scale Core Platform Components: Take responsibility for the design, architecture, and implementation of 1–2 key data platform frameworks within our stack Collaborate and Align: Partner with infra, data science, and product engineering teams to ensure your target platform's capabilities are directly guided by platform governance and product requirements. Optimize Performance at Scale: Dive deep into engine internals, query planning, state management, memory optimization, serialization efficiency to maximize throughput and reliability under heavy load. Drive Infrast

JavaAWSGCPKubernetes
R
📍 San Mateo, CA, United States· Full-time
✓ High-confidence listingCompany trend -100%

From $196.8K/yr

Quick readStrong listing-quality and freshness signals

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. With Roblox’s daily active users growing at a record pace, we are seeking a senior data infrastructure engineer to join our new Data Insights team. Our team owns the data tooling that empowers Roblox builders to independently make informed and timely data-driven decisions. As an engineer on the team, you’ll work on the platforms behind tools like Superset, Hex, and Python notebooks, which provide critical insights into the health of our business to users at every level of the company. We tackle diverse challenges in data engineering, infrastructure, and analytics, to deliver the insights our customers need. You will collaborate closely with engineers across our data ecosystem to shape the future of product analytics at Roblox. This role offers the chance to be a founding team member and help define both the technical direction and the long-term shape of the product area from the ground up. This role is a great fit for you if you are proficient in designing and scale robust data infrastructure and applications and have a zeal for developing inspiring, easily maintainable, and reusable code. Join our team and make a significant impact at Roblox. You Will: Architect and deliver a high-pe

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R
📍 San Mateo, CA, United States· Full-time
✓ High-confidence listingCompany trend -100%

From $242.1K/yr

Quick readStrong listing-quality and freshness signals

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 the Engine DataModel team, you will own and innovate on the foundational components that form the backbone of the Roblox platform. In the Roblox Engine, the DataModel is a tree-like structure that is analogous to a scenegraph in other 3D engines. This role will report to the engineering manager and will be based out of our HQ in San Mateo, CA in a hybrid model 3 days a week (Tuesdays to Thursdays). Our team owns: The core structures and systems are used to build the DataModel and interact with it. The C++ reflection bindings that form the Engine’s Luau API surface and let creators interact with the DataModel. We’ve built custom codegen tooling to generate the C++ for these reflection bindings and other related structures. DataModel serialization … and much more! You will: Develop engine code that performs well for all user-created games on the Roblox platform. Build the core systems and data structures used in the Roblox engine, working with other teams to find universal solutions. Take ownership of projects throughout their full lifecycles. Execute code that performs well on all the devices Roblox supports—from desktop clients to mobile phone clients to con

AWSGitAIC++
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📍 New York, New York, United States· Full-time
✓ High-confidence listingCompany trend -85.2%

From $192K/yr

Quick readStrong listing-quality and freshness signals

Senior Software Engineer - Streaming Platform Client Data streams are mission-critical at Datadog, powering near real-time communication across the vast majority of our services. Our Streaming Platform group builds the core infrastructure and abstractions that ensure Datadog remains a trusted partner for engineers worldwide. See our blog post . The Streaming Platform Client team sits at the heart of this ecosystem. We own the Rust client library (producers and consumers) with language bindings for Java, Go, and Python. We focus on building intuitive APIs and abstractions that make a powerful distributed system easy to adopt and operate for the hundreds of internal users of our library. Our library runs on critical data paths that handle hundreds of millions of messages per second making performance, observability, and reliability paramount. We also develop and operate the service that bridges the clients fleet with the platform's control plane, handling complex balancing, scaling, and static stability challenges. We are seeking a Senior Software Engineer to help us evolve these features. You will collaborate directly with our users, tackle performance-critical code, and solve complex distributed systems challenges across the control plane, client libraries, and data plane. At Datadog, we place value in our office culture - the relationships and collaboration it builds and the creativity it brings to the table. We operate as a hybrid workplace to ensure our Datadogs can create a work-life harmony that best fits them. What You’ll Do: Work within a distributed, high-impact team spanning Europe and the US, building critical technologies that power data pipelines for dozens of internal teams and hundreds of services. Architect and implement resilient interactions between our client libraries and the control plane. Optimize our high-throughput, low-level streaming library to push the boundaries of performance and efficiency. Champion the developer experience by providing

PythonJavaGitAI
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📍 Massachusetts, New York, United States· Full-time
✓ High-confidence listingCompany trend -85.2%

From $192K/yr

Quick readStrong listing-quality and freshness signals

About Datadog: We're on a mission to build the best platform in the world for engineers to understand and scale their systems, applications, and teams. We operate at high scale—trillions of data points per day—providing always-on alerting, metrics visualization, logs, and application tracing for tens of thousands of companies. Our engineering culture values pragmatism, honesty, and simplicity to solve hard problems the right way. You will: Solve a scaling bottleneck in a critical service Deploy a new feature to production, progressively rolling it out with feature flags Investigate and fix a production issue from a service your team owns Design a way to scale up a service for more traffic With your team, plan the most important projects to work on next Who You Are: You have significant experience in one or more languages You value code simplicity and performance You can design architecture to solve problems at high scale You have a BS/MS/PhD in a scientific field or equivalent experience You want to work in a fast, high-growth startup environment that respects its engineers and customers You have demonstrated ability to use AI coding tools in day-to-day workflows and build, validate, and refine AI-generated output in products You can design AI Backend systems, with awareness of quality, cost, and latency tradeoffs 6+ years of experience Bonus points: You've worked at high scale with systems like Redis, Cassandra, Kafka You wrote your own data pipelines once or twice before You have a strong background in statistics You have significant experience with Go, C, or Python You’re excited about leveraging AI tools to enhance how you code, solve problems, and build – or eager to learn how You’re motivated to push the boundaries of how AI can improve software engineering best practices and contribute to building AI-enabled products Datadog values people from all walks of life. We understand not everyone will meet all the above qualificat

PythonRedisAIGo
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📍 New York, New York, United States· Full-time
✓ High-confidence listingCompany trend -85.2%

From $192K/yr

Quick readStrong listing-quality and freshness signals

Senior Software Engineer - Streaming Platform Client Data streams are mission-critical at Datadog, powering near real-time communication across the vast majority of our services. Our Streaming Platform group builds the core infrastructure and abstractions that ensure Datadog remains a trusted partner for engineers worldwide. See our blog post . The Streaming Platform Client team sits at the heart of this ecosystem. We own the Rust client library (producers and consumers) with language bindings for Java, Go, and Python. We focus on building intuitive APIs and abstractions that make a powerful distributed system easy to adopt and operate for the hundreds of internal users of our library. Our library runs on critical data paths that handle hundreds of millions of messages per second making performance, observability, and reliability paramount. We also develop and operate the service that bridges the clients fleet with the platform's control plane, handling complex balancing, scaling, and static stability challenges. We are seeking a Senior Software Engineer to help us evolve these features. You will collaborate directly with our users, tackle performance-critical code, and solve complex distributed systems challenges across the control plane, client libraries, and data plane. At Datadog, we place value in our office culture - the relationships and collaboration it builds and the creativity it brings to the table. We operate as a hybrid workplace to ensure our Datadogs can create a work-life harmony that best fits them. What You’ll Do: Work within a distributed, high-impact team spanning Europe and the US, building critical technologies that power data pipelines for dozens of internal teams and hundreds of services. Architect and implement resilient interactions between our client libraries and the control plane. Optimize our high-throughput, low-level streaming library to push the boundaries of performance and efficiency. Champion the developer experience by pro

PythonJavaGitAI
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📍 Massachusetts, New York, United States· Full-time
✓ High-confidence listingCompany trend -85.2%

From $192K/yr

Quick readStrong listing-quality and freshness signals

Distributed Systems engineers at Datadog design, implement and run in production the foundational platforms powering our applications. Your data pipelines will ingest, store, analyze and query in real-time billions of events per second from companies all over the globe. The platforms are optimized for durability, high availability, low latency, internet-scale footprint and operability. At Datadog, we place value in our office culture - the relationships that it builds, the creativity it brings to the table, and the collaboration of being together. We operate as a hybrid workplace to ensure our employees can create a work-life harmony that best fits them. What You’ll Do: Build fault-tolerant, horizontally scalable solutions running in multi-tenant environments Write in Go, Java Rust or C++, amongst other languages Use Kafka, Redis, Cassandra, Elasticsearch and other open-source components Own meaningful parts of our service, have an impact, grow with the company Who You Are: 6+ years of experience You have a BS/MS/PhD in a scientific field or equivalent experience You have significant backend programming experience in one or more languages (Go, Java, Rust, C++) You have been exposed to working on problems (high durability / low latency /…) You can get down to the low-level when needed You care about simple designs and performance You want to work in a fast, high-growth startup environment that respects its engineers and customers You have demonstrated ability to use AI coding tools in day-to-day workflows and validate, critique, and refine AI-generated output. Bonus: you’re motivated to push the boundaries of how AI can improve software engineering best practices and contribute to building AI-enabled products. This job is available in various departments within our company; to conform to US export control regulations, some of these roles may require candidates to be eligible for any required authorizations from the US government. Datadog values peo

JavaRedisAIC++
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📍 San Francisco, California, United States· Full-time
✓ High-confidence listingCompany trend -50%

$130K – $180K/yr

Quick readStrong listing-quality and freshness signals

About Taskrabbit: Taskrabbit is a marketplace platform that conveniently connects people with Taskers to handle everyday home to-do’s, such as furniture assembly, handyman work, moving help, and much more. At Taskrabbit, we want to transform lives one task at a time. As a company we celebrate innovation, inclusion and hard work. Our culture is collaborative, pragmatic, and fast-paced. We’re looking for talented, entrepreneurially minded and data-driven people who also have a passion for helping people do what they love. Together with IKEA, we’re creating more opportunities for people to earn a consistent, meaningful income on their own terms by building lasting relationships with clients in communities around the world. Taskrabbit is a hybrid company with employees distributed across the US and EU and a Built In — Best Places to Work (2022, 2023, 2024, 2025) continually ranked across multiple national and regional categories. Join us at Taskrabbit, where your work will be meaningful, your ideas valued, and your potential unleashed! Prior to applying please note: W e are currently unable to provide visa sponsorship for this position (including H-1B, OPT, or other employment-based visas). Candidates must be legally authorized to work in the United States without employer sponsorship now or in the future. This role is hybrid requiring 2 days in office at our San Francisco hub every Tuesday & Wednesday (located at 130 Sutter St). About the Role: We're seeking a Senior Software Engineer to join our Post-Booking team, someone who doesn't just build, but raises the quality bar across our entire ecosystem. You'll be instrumental in shaping the consumer experience following the initial booking process. Your work will focus on building new features to improve the customer experience through high-performance Node.js services and AI-driven enhancements, as well as critical replatforming work to modernize our microservice infrastructure. Key Responsibil

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📍 San Francisco, California, United States· Full-time
✓ Quality checkedCompany trend -82%

About the Team The Future of Computing Research team is an Applied Research team within the Consumer Devices group focused on developing new methods and models as we advance forward in our mission of building AGI that benefits all of humanity. As a Software Engineer on the Future of Computing Research team, you will work together with both the best ML researchers in the world and the greatest design talent of our generation to push the frontier of model capabilities. About the Role We are looking for a Software Engineer to join our team to build tools and services that enable AI research, evaluation, and data generation workflows. The best work in this role will start with an ambiguous design question and turn it into working research systems. You will work closely with researchers, designers, and engineers to build the evaluation systems, synthetic data generation pipelines, review tools, and supporting platform services. The goal is to make these workflows easier to create, run, and trust without requiring bespoke engineering support for each new design concept. You will help ensure that research artifacts have a clear lifecycle, runs are reproducible and observable, and results provide useful evidence for product and model-training decisions while the underlying systems remain reliable and reusable. This role is based in San Francisco, CA. We use a hybrid work model of three days in the office per week and offer relocation assistance to new employees. In this role, you will: Build web applications, APIs, data models, and backend services for AI research workflows. Build tools to author and manage evaluation tasks, rubrics, graders, suites, and rollout configurations, including workflows for publishing, versioning, auditing, and sharing research artifacts. Automate evaluation runs and generate useful reports for design, research, and engineering teams. Support synthetic data generation workflows for multimodal and conversational research, including tools that comb

AWSRestAIGo
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📍 New York, California, United States· Full-time
✓ High-confidence listingCompany trend -100%
Quick readStrong listing-quality and freshness signals

Who Are We? Postman is the world’s leading API platform, used by more than 45 million+ developers and 500,000 organizations, including 98% of the Fortune 500. Postman is helping developers and professionals across the globe build the API-first world by simplifying each step of the API lifecycle and streamlining collaboration—enabling users to create better APIs, faster. The company is headquartered in San Francisco and has offices in Boston, New York, Austin, Tokyo, London, and Bangalore - where Postman was founded. Postman is privately held, with funding from Battery Ventures, BOND, Coatue, CRV, Insight Partners, and Nexus Venture Partners. Learn more at postman.com or connect with Postman on X via @getpostman. P.S: We highly recommend reading The "API-First World" graphic novel to understand the bigger picture and our vision at Postman. About Fern, a Postman Company Fern helps software companies build a world-class API experience. Our customers include industry leaders like Nvidia, Square, and Twilio, as well as fast-growing AI companies like ElevenLabs and OpenRouter. In the next year, the majority of API integrations will be implemented by AI agents. Agents don’t read marketing pages. They need strongly typed schemas, structured endpoints, deterministic contracts, and documentation that can be fed into a context window. Our team is small and talent-dense. We’re a team of builders from Google, Palantir, Amazon, and Uber, working together in New York City. About the Role As a Senior Software Engineer at Fern, you’ll build APIs, scale AI infrastructure, and design developer experiences that reach millions of people. Scale infrastructure to keep up with growth: Work on AI systems deployed on Vercel, AWS, and Turbopuffer that must be performant, reliable, and secure under real-world load. Stay close to customers: We work directly with API teams at companies like Nvidia, Twilio, and Square. You’ll debug real production edge cases, shape APIs ba

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