Scientist Analytical Research And Development Jobs

We're transforming the grocery industry At Instacart, we invite the world to share love through food because we believe everyone should have access to the food they love and more time to enjoy it together. Where others see a simple need for grocery delivery, we see exciting complexity and endless opportunity to serve the varied needs of our community. We work to deliver an essential service that customers rely on to get their groceries and household goods, while also offering safe and flexible earnings opportunities to Instacart Personal Shoppers. Instacart has become a lifeline for millions of people, and we’re building the team to help push our shopping cart forward. If you’re ready to do the best work of your life, come join our table. Instacart is a Flex First team There’s no one-size fits all approach to how we do our best work. Our employees have the flexibility to choose where they do their best work—whether it’s from home, an office, or your favorite coffee shop—while staying connected and building community through regular in-person events. Learn more about our flexible approach to where we work. Overview This role challenges traditional approaches to digital shopping by improving backend systems that power a seamless user journey. You will lead efforts to enhance content discoverability and purchase processes, helping to perfect the interaction between user desires and our vast product offerings. The Senior Software Engineer will focus on enhancing the user experience by developing robust backend architectures that support advanced recommendation and personalization systems. In close collaboration with ML engineers, product teams, and data scientists, you will lead the innovation of our backend services, enabling sophisticated, data-driven features that adapt to our customers' shopping behaviors. The Core Experience teams are dedicated to creating engaging and straightforward shopping experiences. You will be part of a team that is at the heart of product

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. The Safety and Customer Care (SCC) team at Lyft manages over 1.7 million monthly human and AI interactions and serves as Lyft's primary direct touchpoint with riders and drivers. We handle critical infrastructure that powers both human associates and AI agents to make riders and drivers feel safe and comfortable while riding or driving with Lyft, transforming every support interaction into a moment of genuine connection. Agentic AI is at the center of how we scale that mission. We fine-tune and align open-source models, build AI-powered support agents, and develop end-to-end AI agents for safety case management, systems that reason over complex, high-stakes cases and drive them to resolution. SCC brings together ML, data, backend, and product engineers alongside data scientists and operations partners to transform these systems. As a Machine Learning Engineer on the SCC team, you will fine-tune and align models and build AI Agents that power how riders and drivers get help. Your work spans the full loop: post-training open-source models for our domain, composing them into multi-step agents, and building the evaluation that proves they are safe to ship in a customer-facing, safety-critical setting. Post-train and adapt open-source LLMs for SCC use cases using SFT, LoRA, and preference-tuning methods (RLHF, RLAIF, RLVR). Design and build AI-powered support agents and end-to-end agents for safety case management using LangGraph or equivalent agentic frameworks. Own the evaluation data flywheel, offline and online, that defines what "good" looks like and build benchmarks for the team to hill-climb. Turn interaction feedback into training data and learning signals, closing the data flywheel that continuously improves the models. Responsibilities: Conduct literature review and build post-training fra

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. The Mapping team at Lyft is tasked with building a digital representation of the physical world - a map. We collect and serve the freshest and most accurate mapping data possible, along with algorithms, models, platform services, and map-based user experiences that power Lyft’s current and future transportation offerings. Mapping represents a huge opportunity for Lyft’s business, but also a big challenge. We build and scale systems that deal with large data storage, real-time data processing, machine / deep learning pipelines, routing and ETA models, driver and passenger location tracking, and more. We built beautiful and magical user experiences on top of all those services, and compete with companies that have been in the mapping business for decades. To strengthen our efforts, we are hiring a Senior ML Engineer who will work end-to-end on creating and improving new capabilities to detect changes in the environment and reflect them in our Lyft map using a wide variety of input sources from the Lyft fleet. For this we are looking for someone who values software engineering best practices, loves the algorithmic and geospatial side of the challenge and is data-driven from start to end. Our technology stack ranges from basic machine learning models to large language models and running them at scale on millions of images. You will work with incredibly passionate and talented colleagues from machine learning, data science, and engineering on projects that delight our passengers and drivers – powered by an up to date map. Responsibilities: Partner with Engineers, Data Scientists, Product Managers, and Business Partners to apply machine learning for business and user impact Perform data analysis and build proof-of-concept to explore and propose ML solutions to both new and existing proble

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. Lyft Ads is building the world's largest mobility advertising network, connecting brands with millions of consumers throughout their transportation journeys. Our mission is to help brands reach riders during key moments of their journey — before, during, and after a ride — by delivering meaningful, contextually relevant ad experiences. Core to that vision is our ad serving platform. Our Ad Serving team builds the systems and integrations that power the delivery of ads, being both thoughtful of our riders’ experience while also driving great outcomes for advertisers. We’re looking for a Staff Product Manager I to architect and reimagine our ad serving platform so that our rapidly growing advertising business can continue to scale. Based out of our New York City office, you’ll own development and the forward-looking vision for the platform that connects advertisers and riders, help us accelerate our capabilities, and execute across a whip-smart, fast-paced team. Responsibilities: Help develop the strategy and objectives for our Ad Serving platform. Build a roadmap and lead a core team of engineers and data scientists to achieve it. Align cross functional partners and teams beyond your immediate development team to drive a shared vision. For example, Sales, Legal, Finance, Operations, and internal marketing teams. Take a holistic yield management approach across direct demand and external supply channels. Clearly communicate priorities, problems, experiments, and decisions across a wide spectrum of audiences, from partner teams to executives. Completely own your team's products, existing or new, from ideation through development, launch, growth, and maintenance. Understand Lyft Ads’ strategic and competitive position. Set your team's goals, success metrics, and roadmap to a

At Lyft, our mission is to improve people’s lives with the world’s best transportation. To do this, we start with our own community by creating an open, inclusive, and diverse organization. We have an ambitious goal to strengthen our international presence by growing a life-changing product, and your efforts will play an essential role in our collective success. Growth teams are at the heart of our products and decision-making to drive business growth. We’re looking for passionate, driven engineers to build systems that empower our users (both Drivers and Riders) to make the most effective use of Lyft’s products and experiences by making them more predictive, personalized, and adaptive. We’re looking for someone who can build & own innovative applications, passionate about solving problems with distributed computing in building reliable systems, and is excited about working in a fast-paced, innovative, and collegial environment. As a Senior Software Engineer, with your technical expertise you will build and own innovative applications with a desire to achieve exceptional design fidelity, usability, accessibility, and performance. You will be responsible for sound technical execution of projects through hands-on development, quality-assurance, and prototyping. These projects will require close collaboration with our product managers, user interface designers, brand producers, data scientists, and engineering teams. You’ll be managing multiple exciting projects at once, so being able to juggle these initiatives is key! We’re also counting on you to be a champion for best engineering practices, guiding engineers, designers, and management along the way. We are looking for candidates who are self starters and have a proven track record of delivering software solutions that can solve critical business needs. We’re looking for a candidate who thrives in tackling complex, ambiguous challenges and can

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. With over half a billion rides and counting, Lyft is solving hard problems in a rapidly growing domain with a lot of data and creative solutions in Marketplace, Mapping, Fraud, Growth and beyond. Building a next-generation platform for low-cost, ultra-immersive transportation to improve people's lives requires robust, scalable software systems operating at massive scale. Our highly motivated Software Engineers work on these challenging problems and build the systems that directly impact various aspects of our core business. If you are a critical thinker with experience building software systems, passionate about solving business problems through well-crafted code and working in a dynamic, creative, and collaborative environment, we are searching for you. As an associate software engineer, you will be designing, building, and launching the services that power the platform's core products. Compared to similarly-sized technology companies, the set of problems that we tackle is incredibly diverse. They cut across transportation, distributed systems, backend services, mapping, personalization, and real-time infrastructure. We are hiring motivated engineers across each of these areas. We're looking for someone who is passionate about solving problems with code, building reliable and maintainable systems, and is excited about working in a fast-paced, innovative, and collegial environment. You will report to a Software Engineering Manager. Responsibilities: Partner with Engineers, Data Scientists, Product Managers, and Business Partners to build software for business and user impact Perform technical analysis and build proof-of-concept prototypes to explore and propose solutions to both new and existing problems Design and develop software components, services, and APIs Write production quality code to launc

At Lyft, our mission is to improve people’s lives with the world’s best transportation. To do this, we start with our own community by creating an open, inclusive, and diverse organization. We have an ambitious goal to strengthen our international presence by growing a life-changing product, and your efforts will play an essential role in our collective success. Growth teams are at the heart of our products and decision-making to drive business growth. We’re looking for passionate, driven engineers to build systems that empower our users (both Drivers and Riders) to make the most effective use of Lyft’s products and experiences by making them more predictive, personalized, and adaptive. We’re looking for someone who can build & own innovative applications, passionate about solving problems with distributed computing in building reliable systems, and is excited about working in a fast-paced, innovative, and collegial environment. As a Senior Software Engineer, with your technical expertise you will build and own innovative applications with a desire to achieve exceptional design fidelity, usability, accessibility, and performance. You will be responsible for sound technical execution of projects through hands-on development, quality-assurance, and prototyping. These projects will require close collaboration with our product managers, user interface designers, brand producers, data scientists, and engineering teams. You’ll be managing multiple exciting projects at once, so being able to juggle these initiatives is key! We’re also counting on you to be a champion for best engineering practices, guiding engineers, designers, and management along the way. We are looking for candidates who are self starters and have a proven track record of delivering software solutions that can solve critical business needs. We’re looking for a candidate who thrives in tackling complex, ambiguous challenges and can

Airbnb was born in 2007 when two hosts welcomed three guests to their San Francisco home, and has since grown to over 5 million hosts who have welcomed over 2 billion guest arrivals in almost every country across the globe. Every day, hosts offer unique stays and experiences that make it possible for guests to connect with communities in a more authentic way. The Community You Will Join: Everyone at Airbnb thinks about trust, but our team obsesses over it daily. At the core of trust is safety, and thus we spend a significant amount of our time and energy keeping the community safe. The Trust team is responsible for developing the technology that helps protect our community and platform from fraud while also ensuring our hosts, guests, homes, and experiences meet our high standards. We constantly work to fight against online fraud (such as monetary loss, compromised accounts, spam and scam in messages, fake inventory, etc.) as well as offline fraud (theft, property damage, personal safety, etc.). We also work on onboarding and screening of users, and think about complex topics like identity and reputation to ensure that every interaction with Airbnb helps build trust in us and our community. The Trust Frontier AI team is where new AI technology for Trust gets invented and proven. We build specialized models for mission-critical trust and safety problems, develop the AI agents and agentic capabilities that automate trust decisions, and create the benchmarks and evaluation harnesses that keep decision quality high as those agents take on more autonomy. We work on problems before the answer is known — prototyping, experimenting, and iterating with our partner teams until a solution proves itself against real business and top line metrics. You'll work side-by-side with talented product managers, data scientists, software engineers, fraud intelligence, and operations teams. Together, you'll design and build ML solutions that have direct, meaningful impact on user trust, b

Airbnb was born in 2007 when two hosts welcomed three guests to their San Francisco home, and has since grown to over 5 million hosts who have welcomed over 2 billion guest arrivals in almost every country across the globe. Every day, hosts offer unique stays and experiences that make it possible for guests to connect with communities in a more authentic way. The Community You Will Join: The Relevance and Personalization team at Airbnb is responsible for search and recommendation across the entire Airbnb digital platform. Be a leader in the team working on critical, impactful projects with focus on developing end-to-end ranking algorithms and ecosystems for optimizing multiple critical business objectives. The Difference You Will Make: We build cutting-edge AI technologies across the end-to-end search ranking product stack w.r.t. data pipelines, feature and model innovations, serving and experimentation efficiency, leveraging rich signals from various types of data (structured, sequential, image, text, etc) at Airbnb. We collaborate closely with teams across Airbnb to develop the ranking solutions and support a healthy marketplace for hosts and guests to further Airbnb’s mission of creating a world where people can Belong Anywhere. Some past publications from the team can be found here: https://sites.google.com/view/airbnb-relevance-publications/home A Typical Day: Work with large scale structured and unstructured data, build and continuously improve cutting edge Machine Learning models for Airbnb product, business and operational use cases. Work collaboratively with cross-functional partners including software engineers, product managers, operations and data scientists, identify opportunities for business impact, understand, refine, and prioritize requirements for machine learning models, drive engineering decisions, and quantify impact. Hands-on develop, productionize, and operate Machine Learning models and pipelines at scale, including both batch and real-

Airbnb was born in 2007 when two hosts welcomed three guests to their San Francisco home, and has since grown to over 5 million hosts who have welcomed over 2 billion guest arrivals in almost every country across the globe. Every day, hosts offer unique stays and experiences that make it possible for guests to connect with communities in a more authentic way. Airbnb was born in 2007 when two hosts welcomed three guests to their San Francisco home, and has since grown to over 5 million hosts who have welcomed over 2 billion guest arrivals in almost every country across the globe. Every day, hosts offer unique stays and experiences that make it possible for guests to connect with communities in a more authentic way. The Community You Will Join: Machine Learning and Artificial Intelligence are at the heart of the Airbnb product. From Trust to Payments, and from Customer Service to Marketing we rely on ML to ensure that guests and hosts have the best possible experience with Airbnb. The CS AI product team is responsible for driving CSxAI (Customer Support x Artificial Intelligence) initiatives by adopting the Generative AI technologies to enable an intelligent, scalable and exceptional service experience. The team develops and enhances various AI models, ML services and tools including LLM fine-tuning, alignment and optimization, RAG/Search, LLM evaluation and testing automation, feedback-based learning and guardrail for a wide range of applications in Airbnb. What you will do: As a principal machine learning engineer, you will be responsible for fine-tuning state-of-the-art LLMs for diverse use cases while optimizing models for high-performance deployment on Airbnb’s ML Infrastructure. You will partner with product managers, software engineers, data scientists and operation teams to brainstorm, design and develop AI products such as AI Assistant, Autonomous agent, recommendation, travel planning, and many more products that make meaningful

Airbnb was born in 2007 when two hosts welcomed three guests to their San Francisco home, and has since grown to over 5 million hosts who have welcomed over 2 billion guest arrivals in almost every country across the globe. Every day, hosts offer unique stays and experiences that make it possible for guests to connect with communities in a more authentic way. The Community You Will Join: At Airbnb, if there’s anything related to money, it comes to the Payments team. We are building a world-class payments and commerce organization - one that currently supports 191+ countries, 70 currencies, connects dozens of payment providers and banks, processes multiple billions of dollars, and empowers more people to participate in our global marketplace. We’re looking for people who know and use Airbnb and believe in what we’re trying to accomplish. Airbnb is a marketplace that connects guests and hosts, and Payments is central to creating the trust that makes every transaction possible. The Platform team plays the role of conductor, bringing together engineers, designers, and data scientists to build great product experiences. Our Payments Platform Managers own outcomes across foundation, growth, and empowerment, setting the vision and strategy, defining the roadmap, and driving execution. The Difference You Will Make: Latin America is one of the fastest-growing and most strategically important payments regions for Airbnb. Winning here means navigating complex, market-specific regulation, deep local payment ecosystems, and fast-moving compliance requirements across Brazil, Mexico, and the broader region — while unlocking meaningful growth through local payment methods, checkout optimization, and installments. We're hiring a Product Manager to own this regional payments portfolio end to end and serve as the product leader for one of Payments' highest-impact areas. A Typical Day: Own the product vision, strategy, and roadmap for regional payments across Brazil, Mexico

Airbnb was born in 2007 when two hosts welcomed three guests to their San Francisco home, and has since grown to over 5 million hosts who have welcomed over 2 billion guest arrivals in almost every country across the globe. Every day, hosts offer unique stays and experiences that make it possible for guests to connect with communities in a more authentic way. The Community You Will Join: At Airbnb, if there’s anything related to money, it comes to the Payments team. We are building a world-class payments and commerce organization - one that currently supports 191+ countries, 70 currencies, connects dozens of payment providers and banks, processes multiple billions of dollars, and empowers more people to participate in our global marketplace. We’re looking for people who know and use Airbnb and believe in what we’re trying to accomplish. Airbnb is a marketplace that connects guests and hosts, and Payments is central to creating the trust that makes every transaction possible. The Platform team plays the role of conductor, bringing together engineers, designers, and data scientists to build great product experiences. Our Payments Platform Managers own outcomes across foundation, growth, and empowerment, setting the vision and strategy, defining the roadmap, and driving execution. The Difference You Will Make: Latin America is one of the fastest-growing and most strategically important payments regions for Airbnb. Winning here means navigating complex, market-specific regulation, deep local payment ecosystems, and fast-moving compliance requirements across Brazil, Mexico, and the broader region — while unlocking meaningful growth through local payment methods, checkout optimization, and installments. We're hiring a Product Manager to own this regional payments portfolio end to end and serve as the product leader for one of Payments' highest-impact areas. A Typical Day: Own the product vision, strategy, and roadmap for regional payments across Brazil, Mexico

Discord has a highly engaged community of millions of daily active users who use the platform for many different reasons, but there’s one thing that nearly everyone does: play video games. Discord plays a uniquely important role in the future of gaming, and we are focused on making it easier and more fun for people to hang out before, during, and after playing games. Every day, millions of gamers gather on Discord to hang out, strategize their next raid, celebrate tournament victories, and build communities around the games they love. Behind every voice channel, every streamer Go Live, every Quest completed, there's data, petabytes of it, telling the story of how people connect through gaming. We're looking for someone who gets excited about building data infrastructure at massive scale and cares deeply about the gaming communities we serve. Someone with passion for building lovable products for Discord users and Discord engineers. We’re building the next generation Data Platform that powers decisions for one of the most vibrant platforms in the world. If you're the kind of Software Engineer who lights up when talking about distributed systems, cares deeply about user privacy, grounding decisions in data, and wants your work to directly impact millions of gamers worldwide, we want to talk to you. To learn more about Discord’s Data Platform, read our engineering blog, including how we built our modern data stack leveraging open-source tools! What You'll Be Doing Build and maintain data infrastructure processing petabytes of data across millions of users Write clean, well-tested code for data ingestion, transformation, and serving systems Own projects end-to-end. From design through deployment and production support Collaborate with data scientists, engineers, and product teams to deliver solutions that power Discord's insights Apply 80/20 thinking to challenge requirements, cut unnecessary complexity, and deliver the optimal solution

Airbnb was born in 2007 when two hosts welcomed three guests to their San Francisco home, and has since grown to over 5 million hosts who have welcomed over 2 billion guest arrivals in almost every country across the globe. Every day, hosts offer unique stays and experiences that make it possible for guests to connect with communities in a more authentic way. The Community You Will Join: Machine Learning and Artificial Intelligence are at the heart of the Airbnb product. From Trust to Payments, and from Customer Service to Marketing we rely on ML to ensure that guests and hosts have the best possible experience with Airbnb. The CS AI product team is responsible for driving CSxAI (Customer Support x Artificial Intelligence) initiatives by adopting the Generative AI technologies to enable an intelligent, scalable and exceptional service experience. The team develops and enhances various AI models, ML services and tools including LLM fine-tuning, alignment and optimization, RAG/Search, LLM evaluation and testing automation, feedback-based learning and guardrail for a wide range of applications in Airbnb. The Difference You Will Make: As a senior staff machine learning engineer, you will be responsible for fine-tuning state-of-the-art LLMs for diverse use cases while optimizing models for high-performance deployment on Airbnb’s ML Infrastructure. You will partner with product managers, software engineers, data scientists and operation teams to brainstorm, design and develop AI products such as AI Assistant, Autonomous agent, recommendation, travel planning, and many more products that make meaningful impacts in the world of travel. A Typical Day: Work with large scale structured and unstructured data; explore, experiment, build and continuously improve foundation models for Airbnb product, business and operational use cases. Create a multi-year tech roadmap that enables our team to stay on the leading edge of the rapidly evolving AI landscape and

Airbnb was born in 2007 when two hosts welcomed three guests to their San Francisco home, and has since grown to over 5 million hosts who have welcomed over 2 billion guest arrivals in almost every country across the globe. Every day, hosts offer unique stays and experiences that make it possible for guests to connect with communities in a more authentic way. The Community You Will Join: The Host Pricing & Settings team builds the platform and tools that help hosts run their business — with pricing strategies informed by market intelligence, comparable listings, and demand signals. We partner with Search, Listings, Tax, and Payments to ensure our guidance is accurate, timely, and trusted. Behind every pricing recommendation is a sophisticated ML system undergoing a fundamental rearchitecture. Our north star: a serving infrastructure where training, inference, and evaluation are consistent by design — features from a centralized store, model composition in one place, and backfills available on demand so data scientists and MLEs can evaluate candidates in days, not weeks. The Difference You Will Make: As a senior technical individual contributor, you will own the technical strategy for the full Modeling → ML Serving → API interface across the Host Pricing org. Although you will be at one of our highest levels of seniority, all individual contributors at Airbnb are Software Engineers — you are expected to be hands-on and contribute code. Define the architecture and contracts governing how models move from development to production — feature store design, model schema management, online/offline inference consistency, and multi-version support. Lead the buildout of a unified serving stack that eliminates per-model one-off implementations and gives data scientists a turnkey path from training to production. Architect backfill and evaluation infrastructure so the modeling team can simulate production inference over historical data in days, not weeks. Establish do