Belinda Zeng, the head of applied science and engineering at Amazon Search Science and AI, is seen standing outside in Costa Rica on a sunny day, a wire fence is just behind her in the foreground, and a valley and mountains are seen in the background
Belinda Zeng is the head of applied science and engineering at Amazon Search Science and AI.
Courtesy of Belinda Zeng

How to build a successful career as a scientist at Amazon

Belinda Zeng, head of applied science and engineering at Amazon Search Science and AI, shares her perspective.

Editor’s note: Belinda Zeng joined Amazon in 2017 as the global head of data science and has participated in hundreds of interviews for science roles across the company. Here she shares her thoughts on what it takes to succeed as a scientist at Amazon.

I have had the pleasure of working at Amazon as a science leader for the past four-plus years. Two years ago I became what is known in Amazon as a Bar Raiser. Bar Raisers are experienced interviewers who help to raise the Amazon recruiting standard. I lead a science and engineering team called M5 — the five Ms stand for multi-lingual, multi-locale, multi-modal, multi-task, multi-entity — a large-scale AI program focused on transforming how deep learning models are built and deployed at Amazon. My team innovates to help bring Amazon services beyond the current state of the art, achieve step function improvement, and unlock many new downstream applications in search, advertising, and catalog, to name just a few.

Looking back on my journey at Amazon, and drawing on my experience as a Bar Raiser, I’d like to share some information and advice with those who are interested in exploring opportunities with Amazon.

What does the hiring team look for?

I still remember the day when I submitted my application to Amazon, wondering what the hiring team was seeking. Four years later, I know the answer to that question.

First and foremost are the functional competencies, including science breadth, depth, experience in developing science applications, and scripting language coding skills. There are a number of science roles within Amazon and because the core responsibilities for those roles are distinct, the required technical skills differ.

Related content
Amazon's Daliana Liu helps others in the field chart their own paths.

Data scientists, for example, are considered as generalists who investigate the feasibility of applying scientific principles to business problems. They are normally assessed for data skills, math/stats knowledge and, most likely, analytical mindset, and business acumen.

Research and applied scientists are expected to have deep expertise in one of the data-driven science disciplines and to apply scientific principles to support significant invention. The hiring team typically delves into one or two scientific areas such as machine learning, speech recognition, operations research, and robotics.

Development of software code is a core skill expected from applied scientists as they are deeply involved in bringing their algorithms to production. Economists are vetted for their experience developing offline code for applied econometric applications. The second area we assess is how well applicants can apply the Amazon Leadership Principles. In the more than 200 loops (Amazon’s name for our interview process) in which I have participated, three Leadership Principles stand out for scientists:

  • Learn and Be Curious: In my interview conversations, I look for data points that show the candidate proactively seeking opportunities to learn new skills and improve themselves versus staying with familiar situations or avoiding new experiences.
  • Dive Deep: I look for those who investigate and get details to solve a problem, even when faced with challenges, as opposed to having only a surface-level understanding of projects;
  • Invent and Simplify: I look for those who generate new ideas or simplify a solution for long-term wins versus creating a cumbersome process to solve a short-term problem.
Related content
What's it like to be a scientist at Amazon? What drew you to science? What advice do you have? We asked those questions a lot in 2021 — these are some of the best answers.

For senior level roles, a writing exercise is normally required as well. Amazon uses written documents to communicate ideas and influence others. We look for candidates who are able to articulate a process, product or point of view in a clear, crisp, and logical manner.

During the interview debrief, we often debate whether a candidate “raises the bar”. A bar-raising candidate is a candidate who is better qualified than 50% of existing employees at the same level. For entry level roles, it means the ability to fulfill a task with supervision. For experienced hires, it means to deliver with autonomy and minimum supervision.

How does Amazon support its scientists?

For scientists hired by Amazon, there are many types of career support available from both your team and the company.

Learning: Amazon seeks candidates who are passionate lifetime learners, and provides numerous opportunities to support that instinct. That can come in the form of online and classroom courses, team wiki and learning portals, as well as access to experts and mentorship. For example, 200 Amazon scientists were randomly selected to participate in a Coursera beta program to take free online courses for six months. The scientists were able to stay current in their science specialty and increase their skills and knowledge to apply on their job.

In addition, there is a special program called the Day 1 Science Mentorship Program. That program pairs up new-hire scientists with experienced Amazon science leaders to ease the transition into Amazon’s business culture.

Related content
An Amazon principal scientist describes how an internal challenge has fostered greater collaboration and a sense of community among the company’s scientists.

Community connection: An expansive community is critical to a scientist’s development. At Amazon, there are hundreds of science-focused meetings, reading clubs, invited talk series, and workshops happening on a regular basis. These mechanisms not only offer the opportunity to connect with people who have similar research interests, but also provide a forum to showcase innovative work.

The company also holds multiple annual science conferences for Amazonians interested in innovative science. One is the annual Amazon Machine Learning Conference, a four-day event that covers most major areas in machine learning and attracts thousands of attendees and submissions. Collectively we continually raise the scientific bar at Amazon.

Growth: At Amazon, we all grow with the company. There are ample opportunities to stretch yourself, by expanding your scope and growing your skill set. I have helped scientists on my team transition into different science roles; relocate internationally for a stretching assignment; and watched some go from individual contributors to tech leads and eventually managerial positions.

How do you build a successful career at Amazon?

Here are some insights from my personal experience:

Trust is a multiplier. There are multiple meanings inside this single word: transparency, integrity, capability, and many more. For scientist roles, trust naturally expands with competency — stay fresh, relevant and capable — and contribution, which means producing high quality, timely results. I have worked with many great scientists and observed how they build trust through capability and results, which in turn brought greater influence. A common pitfall is sometimes we tend “assume” trust by overestimating our capabilities. Consistently asking for feedback, then listening to and acting on that feedback will help close that gap and build trust.

Related content
Alex Guazzelli, director of machine learning in Amazon’s Customer Trust and Partner Support unit, says great scientists are the ones that spend time learning and improving themselves.

Work backwards from a problem. New scientist hires, especially those who recently moved from a foundational research role, sometimes find it hard to transition into the Amazon working backwards culture. The goals in foundational research are to generate knowledge or understanding regarding a particular phenomenon, without much focus on real-world impact. However, for applied research at Amazon, the main criterion of success lies in how well findings can be used to have a positive impact on customers. A well-balanced focus between curiosity- and solution-driven research is key to ensure effective execution.

Be a well-rounded scientist. Being a scientist means more than running experiments. Scientists are expected to understand the business problem, decompose a complex issue into components that are addressable by science, and communicate science effectively. Success is the journey, not the destination. If you are interested in joining Amazon’s customer-obsessed journey, please visit the Amazon Science careers page. It is always Day 1 at Amazon.

Related content

IN, TS, Hyderabad
Are you passionate about solving complex problems with machine learning and scientific rigor? As an Applied Scientist I at Amazon, you will translate real-world business challenges into well-defined scientific problems and build solutions that directly benefit customers. You will work alongside experienced scientists and engineers, applying your expertise in areas such as natural language processing, computer vision, or robotics to design experiments, develop models, and deliver production-ready code. This is a role where your curiosity and technical depth will drive meaningful impact from day one. Key job responsibilities - Design, develop, and implement machine learning models and algorithms to solve well-defined business problems, mapping business goals and metrics to scientific approaches and evaluation criteria. - Write secure, stable, testable, and maintainable production code, applying state-of-the-art data structures and algorithms while following software development best practices at a high quality bar. - Conduct rigorous experiments to evaluate model performance, benchmark results against current research, and iterate on solutions to improve accuracy and customer outcomes. - Collaborate with team members to scope technical approaches, communicate findings through internal research reports, and contribute to peer-reviewed publications when aligned with business needs. - Stay current with research trends in your area of expertise, champion the adoption of recent scientific advancements, and help onboard and mentor scientist interns. A day in the life You might start your morning reviewing experiment results from a model you trained, analyzing performance metrics and identifying areas for improvement. After a design discussion with your team, you refine your approach and push updated code for review. In the afternoon, you read a recent research paper recommended by a senior scientist, exploring whether a new technique could improve your current solution. You wrap up by documenting your methodology so teammates can understand and build on your work. About the team Our team is focused on applying scientific methods and machine learning to solve problems that matter to Amazon's customers. We value rigorous experimentation, clear communication, and a collaborative environment where scientists at every stage of their career can grow. We are building toward solutions that push the boundaries of what is possible, and we are looking for curious, thoughtful scientists who want to contribute to that mission and learn alongside a supportive group of peers.
IN, TS, Hyderabad
Welcome to the Worldwide Returns & ReCommerce team (WWR&R) at Amazon.com. WWR&R is an agile, innovative organization dedicated to ‘making zero happen’ to benefit our customers, our company, and the environment. Our goal is to achieve the three zeroes: zero cost of returns, zero waste, and zero defects. We do this by developing products and driving truly innovative operational excellence to help customers keep what they buy, recover returned and damaged product value, keep thousands of tons of waste from landfills, and create the best customer returns experience in the world. We have an eye to the future – we create long-term value at Amazon by focusing not just on the bottom line, but on the planet. We are building the most sustainable re-use channel we can by driving multiple aspects of the Circular Economy for Amazon – Returns & ReCommerce. Amazon WWR&R is comprised of business, product, operational, program, software engineering and data teams that manage the life of a returned or damaged product from a customer to the warehouse and on to its next best use. Our work is broad and deep: we train machine learning models to automate routing and find signals to optimize re-use; we invent new channels to give products a second life; we develop highly respected product support to help customers love what they buy; we pilot smarter product evaluations; we work from the customer backward to find ways to make the return experience remarkably delightful and easy; and we do it all while scrutinizing our business with laser focus. You will help create everything from customer-facing and vendor-facing websites to the internal software and tools behind the reverse-logistics process. You can develop scalable, high-availability solutions to solve complex and broad business problems. We are a group that has fun at work while driving incredible customer, business, and environmental impact. We are backed by a strong leadership group dedicated to operational excellence that empowers a reasonable work-life balance. As an established, experienced team, we offer the scope and support needed for substantial career growth. Amazon is earth’s most customer-centric company and through WWR&R, the earth is our customer too. Come join us and innovate with the Amazon Worldwide Returns & ReCommerce team! Key job responsibilities * Design, develop, and evaluate highly innovative models for Natural Language Programming (NLP), Large Language Model (LLM), or Large Computer Vision Models. * Use SQL to query and analyze the data. * Use Python, Jupyter notebook, and Pytorch to train/test/deploy ML models. * Use machine learning and analytical techniques to create scalable solutions for business problems. * Research and implement novel machine learning and statistical approaches. * Mentor interns. * Work closely with data & software engineering teams to build model implementations and integrate successful models and algorithms in production systems at very large scale. About the team When a customer returns a package to Amazon, the request and package will be passed through our WWRR machine learning (ML) systems so that we could improve the customer experience, identify return root cause, optimize re-use, and evaluate the returned package. Our problems touch multiple modalities spanning from: textual, categorical, image, to speech data. We operate at large scale and rely on state-of-the-art modeling techniques to power our ML models: XGBoost, BERT, Vision Transformers, Large Language Models.
US, CA, San Diego
Amazon Leo is an initiative to launch a constellation of Low Earth Orbit satellites that will provide low-latency, high-speed broadband connectivity to unserved and underserved communities around the world. Come work at Amazon! The Role: Be part of the team defining the overall communication system and architecture of Leo’s broadband wireless network. This is a unique opportunity to innovate and define groundbreaking wireless technology with few legacy constraints. The team develops and designs the communication system of Leo and analyzes its overall system level performance such as for overall throughput, latency, system availability, packet loss etc. This role in particular will be responsible for leading the effort in integration, verification and testing of the systems especially focused on MAC and higher layer testing. This role will also be responsible developing and testing advanced L1/L2/L3 concept to improve the performance and reliability of the LEO network. This role will also be part of a team and develop simulation tools with particular emphasis on modeling the physical layer aspects such as advanced receiver modeling and abstraction, interference cancellation techniques, FEC abstraction models etc. In this role you will: - Work within a project team and take the responsibility for the Leo’s communication system design, system integration and verification. - Work as a part of the team in building a suite of system and network simulation services in Matlab / C++ / Python - Develop requirements from system level to HW/SW level and define test cases associated with the requirements. - Identify additional HW and SW that are needed for the purposes of verification and guide the HW/SW development team in the development of these test solutions/tools// - Work closely with implementation teams to simulate expected system level performance and provide quick feedback on potential improvements - Write scripts / code for functions / features required for specific simulation, testing and verification of given RF system EXPORT CONTROL REQUIREMENTS Due to applicable export control laws and regulations, candidates must be a U.S. citizen or national, U.S. permanent resident (i.e., current Green Card holder), or lawfully admitted into the U.S. as a refugee or granted asylum.
US, TX, Austin
Amazon Leo is an initiative to launch a constellation of Low Earth Orbit satellites providing low-latency, high-speed broadband connectivity to unserved and underserved communities around the world. As a Communication Systems Research Scientist, this role owns the research and system design of the radio resource management (RRM) and radio access layers of Amazon Leo’s direct-to-device (D2D) system, delivering 3GPP-compliant service to unmodified commercial handsets. The Role: Be part of the team defining the communication system and architecture of Amazon’s direct-to-device wireless network and analyzing its system level performance: beam and cell capacity, spectral efficiency, coverage, latency and service availability. This is a unique opportunity to innovate with few legacy constraints, in a segment where the standard itself is still being written. This role leads the research and system design of radio resource management (RRM) for a 3GPP Non-Terrestrial Network (NTN), where D2D upends terrestrial assumptions: a power-limited handset with a near-isotropic antenna, very large cells, hopping beams, large time-varying delay and Doppler, and scarce shared spectrum. RRM in time, frequency and spatial domains is the focus, but the role reasons across the stack, from L1/L2 up through RRC, NAS and 5GC interworking. Agentic AI is expected to be a standard part of the work for development, optimization, tests and debugging, with the scientist accountable for the algorithms, models and conclusions. Export Control Requirement: Due to applicable export control laws and regulations, candidates must be a U.S. citizen or national, U.S. permanent resident (i.e., current Green Card holder), or lawfully admitted into the U.S. as a refugee or granted asylum. Key job responsibilities • Research, design and specify RRM algorithms for Amazon Leo’s 3GPP-based D2D system: MAC scheduling, link adaptation, power control, HARQ strategy, DRX, admission and congestion control, and load balancing, mapping 5QI and QoS flow requirements to scheduler behavior across voice, messaging, emergency and data services. • Treat beam management as part of joint resource optimization, not a standalone process, optimizing it with band assignment, packet scheduling and user pairing in multi-user MIMO (MU-MIMO). • Define the RRM framework for NTN conditions: earth-fixed and earth-moving cells, large time-varying propagation delay, ephemeris-assisted timing and Doppler pre-compensation, extended timing advance, selective HARQ feedback disabling, feeder link and satellite handovers, and interference and spectrum sharing across beams, satellites and terrestrial networks using the same MNO spectrum. • Design mobility and service continuity for a network where the base stations (i.e., satellites) move rather than the user: idle and connected mode mobility, location and time based conditional handover, cell reselection, paging, tracking area design, and NTN-to-terrestrial continuity. • Specify supporting L1/L2 elements with the PHY team: numerology under Doppler, PRACH and initial access, coverage enhancement through repetition, synchronization at low SNR, receiver abstraction, and FEC and BLER modeling for link adaptation. • Keep the radio design coherent with the networking layers: RRC and NAS, RLC and PDCP over long-RTT links, CU/DU split, NTN gateway and 5GC/EPC integration, and transport behavior. • Develop link-level and system-level simulators capturing constellation dynamics, beam patterns, handset characteristics, traffic models and RRM behavior, and use agentic AI across that loop: build and refactor simulation code, scale parameter sweeps, optimize scheduler and link adaptation parameters, explore configuration spaces too large to sweep by hand, maintain regression tests, and triage failures across logs, traces and over-the-air captures. • Translate research into system requirements and implementation-level specifications, and work with modem, payload, ground, RF, ASIC and Testbed teams through integration, field trials and link bring-up, root-causing gaps between simulation, implementation and over-the-air behavior in a fast-paced environment. • Represent Amazon Leo in 3GPP and other standards development organizations, develop and defend contributions on NTN and D2D work items, and contribute patents and publications.
US, WA, Seattle
Amazon Economics is seeking Structural IO Economist (STRUC) Interns who are passionate about applying structural econometric methods to solve real-world business challenges. STRUC economists specialize in the econometric analysis of models that involve the estimation of fundamental preferences and strategic effects. In this full-time internship (40 hours per week, with hourly compensation), you'll work with large-scale datasets to model strategic decision-making and inform business optimization, gaining hands-on experience that's directly applicable to dissertation writing and future career placement. By applying to this role, you are automatically being considered for all our available STRUC internships in 2027. Key job responsibilities As a STRUC Economist Intern, you'll specialize in structural econometric analysis to estimate fundamental preferences and strategic effects in complex business environments. Your responsibilities include: - Analyze large-scale datasets using structural econometric techniques to solve complex business challenges - Applying discrete choice models and methods, including logistic regression family models (such as BLP, nested logit) and models with alternative distributional assumptions - Utilizing advanced structural methods including dynamic models of customer or firm decisions over time, applied game theory (entry and exit of firms), auction models, and labor market models - Building datasets and performing data analysis at scale - Collaborating with economists, scientists, and business leaders to develop data-driven insights and strategic recommendations - Tackling diverse challenges including pricing analysis, competition modeling, strategic behavior estimation, contract design, and marketing strategy optimization - Helping business partners formalize and estimate business objectives to drive optimal decision-making and customer value - Build and refine comprehensive datasets for in-depth structural economic analysis - Present complex analytical findings to business leaders and stakeholders
US, VA, Arlington
Want to help Amazon tell its customer-centric story around the world and work in a highly cross-functional environment with economists, lawyers, scientists, public policy, public relations, and business teams? If yes, keep reading! You'll join a team of economists, engineers, and lawyers to develop economic analysis and evidence supporting legal and regulatory matters across all our lines of business worldwide—including retail, marketplace services, AWS, consumer experience, shopping and search, and operations. In this role, you will have exposure to complex regulatory issues that are of high strategic importance to the company and will develop significant expertise on the economics of Amazon’s business operations and the industries in which it operates. Key job responsibilities: • Provide data-driven guidance on high-stakes legal and regulatory questions facing Amazon worldwide • Collaborate with economists, scientists, engineers, and non-technical partners on high-impact projects with global scope • Partner with global public policy teams to apply economic analyses to current policy debates on competition, AI, and related issues • Engage with external stakeholders to drive deeper understanding of Amazon’s business model and the value it develops for the economy • Support requests for economic analyses and data in ongoing regulatory and litigation matters worldwide • Synthesize business facts and data into compelling economic narratives, translating complex findings into actionable insights • Advise stakeholders across Amazon on a broad spectrum of complex and often novel economic issues • Conduct, direct, and coordinate all phases of research projects—defining key questions, evaluating methodology, executing analysis, and communicating results If you're an economist with a passion for the current legal and policy debate, strong practical judgment and creative problem-solving skills, a love of communicating economic ideas to non-technical audiences, a knack for distilling data and economic models into key insights, and a track record of delivering results fast, we want to talk to you! Internal job description Basic qualifications • PhD in Economics or closely related field Preferred qualifications • 5+ years of economic consulting, regulatory, or policy-relevant experience. • Significant economic consulting, regulatory, or policy-relevant experience • Broad experience consulting on international competition litigation and regulatory issues, including in emerging economies. • Multilingual verbal and written communications skills. • Strong background in program evaluation methods, empirical industrial organization methods, applications to business problems, and/or big data. • Ability to work in a fast-paced business environment. • Strong research track record. • Preferred specialties in applied micro or empirical IO, but behavioral economists and generalists with significant competition experience are also encouraged to apply. • Familiarity with government data sources. • Familiarity with Internet, software, and/or media industries and the legal and regulatory environment in which they operate. • Exceptional verbal and written communications skills.
US, WA, Seattle
Amazon Economics is seeking Reduced Form Causal Analysis (RFCA) Economist Interns who are passionate about applying econometric methods to solve real-world business challenges. RFCA represents the largest group of economists at Amazon, and these core econometric methods are fundamental to economic analysis across the company. In this a full-time internship (40 hours per week, with hourly compensation). You'll work with large-scale datasets to analyze causal relationships and inform strategic business decisions, gaining hands-on experience that's directly applicable to dissertation writing and future career placement. By applying to this role, you are automatically being considered for all our available RFCA internships in 2027. Key job responsibilities As an RFCA Economist Intern, you'll specialize in econometric analysis to determine causal relationships in complex business environments. Your responsibilities include: - Analyze large-scale datasets using advanced econometric techniques to solve complex business challenges - Applying econometric techniques such as regression analysis, binary variable models, cross-section and panel data analysis, instrumental variables, and treatment effects estimation - Utilizing advanced methods including differences-in-differences, propensity score matching, synthetic controls, and experimental design - Building datasets and performing data analysis at scale - Collaborating with economists, scientists, and business leaders to develop data-driven insights and strategic recommendations - Tackling diverse challenges including program evaluation, elasticity estimation, customer behavior analysis, and predictive modeling that accounts for seasonality and time trends - Build and refine comprehensive datasets for in-depth economic analysis - Present complex analytical findings to business leaders and stakeholders
US, MA, Boston
We are looking for researchers who aim to build super-intelligent AI systems that leverage proof assistants to guide learning and reasoning. Our neuro-symbolic AI technology is applied across a wide range of science and engineering domains within Amazon, and you will join the team at the forefront of this research. As an Applied Scientist, you will play a pivotal role in shaping the definition, vision, and development of product features from beginning to end. You will: - Define and implement new neuro-symbolic applications that employ scalable and efficient approaches to solve complex problems. - Work in an agile, startup-like development environment, where you are always working on the most important stuff. - Deliver high-quality scientific artifacts. About the team We work closely with academia. Our team includes an Amazon Scholar in mathematics, and we maintain active research collaborations with faculty at leading CS departments (MIT, Berkeley, CMU).
IN, KA, Bengaluru
RBS (Retail Business Services) Tech team works towards enhancing the customer experience (CX) and their trust in product data by providing technologies to find and fix Amazon CX defects at scale. Our platforms help in improving the CX in all phases of customer journey, including selection, discoverability & fulfilment, buying experience and post-buying experience (product quality and customer returns). The team also develops GenAI platforms for automation of Amazon Stores Operations. As a Sciences team in RBS Tech, we focus on foundational ML research and develop scalable state-of-the-art ML solutions to solve the problems covering customer experience (CX) and Selling partner experience (SPX). We work to solve problems related to multi-modal understanding (text and images), task automation through multi-modal LLM Agents, supervised and unsupervised techniques, multi-task learning, multi-label classification, aspect and topic extraction for Customer Anecdote Mining, image and text similarity and retrieval using NLP and Computer Vision for product groupings and identifying duplicate listings in product search results. Key job responsibilities As an Applied Scientist, you will be responsible to design and deploy scalable GenAI, NLP and Computer Vision solutions that will impact the content visible to millions of customer and solve key customer experience issues. You will develop novel LLM, deep learning and statistical techniques for task automation, text processing, image processing, pattern recognition, and anomaly detection problems. You will define the research and experiments strategy with an iterative execution approach to develop AI/ML models and progressively improve the results over time. You will partner with business and engineering teams to identify and solve large and significantly complex problems that require scientific innovation. You will help the team leverage your expertise, by coaching and mentoring. You will contribute to the professional development of colleagues, improving their technical knowledge and the engineering practices. You will independently as well as guide team to file for patents and/or publish research work where opportunities arise. The RBS org deals with problems that are directly related to the selling partners and end customers and the ML team drives resolution to organization level problems. Therefore, the Applied Scientist role will impact the large product strategy, identifies new business opportunities and provides strategic direction which is very exciting.
IN, KA, Bengaluru
Amazon Advertising Trust is on a mission to redefine how trust is enforced at internet scale, and we are looking for exceptional scientists to help lead the way. We are building systems that reason about advertising content the way a trained human would, at a industry leading volume and speed, and that keep working when the rules change underneath them. At Ads Trust Science we leverage machine learning, generative AI, and large-scale retrieval to solve some of the most complex decision problems for ads worldwide. Every ad shown across Amazon's owned-and-operated properties and third-party networks, in every format and every global marketplace, depends on decisions our systems make. We are just getting started. As a Senior Applied Scientist you will be at the forefront of this work. You will own science problems end to end, bridging the gap between research and production impact. You will not be handed a specification. You will be given a customer problem, a system that partly solves it, and the latitude to decide what to build next. This is a unique opportunity to work at the intersection of multimodal understanding, large language models, and large-scale retrieval, on a problem where the science is genuinely unsettled. You will work alongside scientists whose models run in front of hundreds of millions of customers, at a scale that changes which approaches are even possible. A day in the life - Ship a model into production, then find and document where it fails once real traffic reaches it. - Drive the technical discussion, inside your team and with partner teams, on how to close that gap. - Bring a fresh angle to a problem that is not yours and help a peer get further than they would have alone, building trust across the team in the process. - Mentor while staying hands-on. At this level the design and the code are both yours. About the team Ads Trust Science is a group of scientists who would rather change what the team measures than optimise the wrong number. We value curiosity, rigour, and a bias for action. We expect people to disagree with evidence, to say clearly what did not work, and to iterate quickly toward the solutions that matter.