Why Join Flux?At Flux, we are revolutionizing hardware development by creating the world's first AI Hardware Engineer. Our mission is to democratize access to cutting-edge hardware technology and transform how electronics are conceived and manufactured globally.Role OverviewAs a Software Engineer focusing on Agentic Development, you will be integral in building the core intelligence of our platform. You will develop innovative workflows, reasoning graphs, and seamless integrations that empower both novice users to transform ideas into manufacturable hardware and experienced electrical engineers to learn from past production challenges.Your role will uniquely merge web engineering with AI system design, utilizing TypeScript and LangGraph to embed smart functionalities directly into our design environment.Key ResponsibilitiesCraft agentic reasoning capabilities using TypeScript (LangGraph).Incorporate AI functionalities into the Flux web application (React/Redux) and Chat UI.Implement telemetry and logging systems to monitor runtime health, performance, and cost efficiency.Collaborate with product and electrical engineers to enhance intelligent ECAD workflows.Design and evaluate experiments; convert insights into actionable engineering decisions.Contribute to the development of agentic patterns, conventions, and best practices across the engineering organization.

About Our TeamAt OpenAI, our Hardware team is at the forefront of developing cutting-edge silicon and comprehensive system solutions tailored to the specific needs of advanced AI workloads. We pride ourselves on crafting the next generation of AI-native silicon, collaborating closely with software engineers and research teams to ensure our hardware is seamlessly integrated with AI models. Our mission extends beyond creating production-grade silicon for OpenAI’s supercomputing infrastructure; we also innovate custom design tools and methodologies that spark innovation and enable hardware specifically optimized for AI.About the RoleAs a Software Engineer on the Scaling team, you will play a pivotal role in designing and optimizing the foundational stack that manages computation and data flow across OpenAI’s supercomputing clusters. Your responsibilities will include crafting high-performance runtimes, developing custom kernels, enhancing compiler infrastructure, and building scalable simulation systems to validate and optimize distributed training workloads.This position requires you to work at the intersection of systems programming, machine learning infrastructure, and high-performance computing, where you will create intuitive developer APIs alongside highly efficient runtime systems. You will balance usability and introspection with the imperative for stability and performance across our dynamic hardware landscape.This role is based in San Francisco, CA, featuring a hybrid work model (three days in-office per week). Relocation assistance is provided.Key Responsibilities:Design and implement APIs and runtime components to efficiently manage computation and data movement for diverse ML workloads.Enhance compiler infrastructure by developing optimizations and compiler passes to accommodate evolving hardware advancements.Engineer and refine compute and data kernels, ensuring precision, high performance, and compatibility across simulation and production settings.Analyze and optimize system bottlenecks, focusing on I/O, memory hierarchy, and interconnects at both local and distributed scales.Create simulation infrastructure to validate runtime behaviors, test modifications to the training stack, and support the early development of hardware and systems.Quickly deploy updates to runtime and compiler across new supercomputing builds in close collaboration with hardware and research teams.Work across a varied tech stack, primarily utilizing Rust and Python, with a chance to influence architectural decisions within the training framework.

About Our TeamAt OpenAI, our Hardware organization is at the forefront of developing cutting-edge silicon and system-level solutions tailored for the specific demands of advanced AI workloads. Our team is dedicated to creating the next generation of AI-native silicon, collaborating closely with software and research partners to co-design hardware that is seamlessly integrated with AI models. We not only deliver production-grade silicon for OpenAI’s supercomputing infrastructure but also innovate custom design tools and methodologies that drive acceleration and optimization specific to AI.About This RoleAs a member of our hardware optimization and co-design team, you will play a crucial role in co-designing future hardware from various vendors, focusing on programmability and high performance. You will partner with our kernel, compiler, and machine learning engineers to comprehend their distinct requirements concerning ML techniques, algorithms, numerical approximations, programming expressivity, and compiler optimizations. Your advocacy for these constraints will help shape and influence future hardware architectures aimed at efficient training and inference for our models. If you are passionate about efficiently distributing large language models across devices, optimizing system-wide networking bottlenecks, and customizing the compute pipeline and memory hierarchy of hardware platforms while simulating workloads at various abstraction levels, then this opportunity is perfect for you!This position is based in San Francisco, CA, utilizing a hybrid work model of three days in the office each week, with relocation assistance available for new hires.Key Responsibilities:Collaborate on the co-design of future hardware focusing on programmability and performance with hardware vendors.Support hardware vendors in developing optimal kernels and integrating support within our compiler.Generate performance estimates for critical kernels across diverse hardware configurations, influencing decisions regarding compute core and memory hierarchy features.Create system performance models at various abstraction levels and conduct analyses to guide decisions on scaling and front-end networking.Engage with machine learning engineers, kernel engineers, and compiler developers to align on high-performance accelerator needs.Facilitate communication and coordination with internal and external partners.Shape the roadmap for hardware partners to optimize their products for our AI capabilities.

About Our TeamAt OpenAI, the Fleet team is integral to maintaining the robust computing environment that fuels our groundbreaking research and innovative product development. We manage extensive systems encompassing data centers, GPUs, networking, and more, ensuring optimal performance, availability, and efficiency. Our efforts empower OpenAI’s models to function seamlessly at scale, supporting both internal R&D and external offerings like ChatGPT. We emphasize safety, reliability, and responsible AI deployment over unrestrained growth.About the RoleAs a Software Engineer on the Fleet Hardware team, you will play a crucial role in ensuring the reliability and uptime of OpenAI’s compute fleet. Minimizing hardware failures is essential for research training progress and service stability since even minor disruptions can lead to significant setbacks. With the increasing complexity of supercomputers, the pressure to maintain operational integrity has never been higher.This is a unique opportunity to be at the forefront of technology, pioneering solutions for troubleshooting advanced systems on a large scale. You will work with cutting-edge technologies and innovate solutions to ensure the health and efficiency of our supercomputing infrastructure.Our team empowers skilled engineers with a significant degree of autonomy and ownership, enabling them to drive impactful change. This role requires a keen focus on comprehensive system investigations and the development of automated solutions. We seek individuals who dive deep into problems, conduct thorough investigations, and create automation for large-scale detection and remediation.In this Role, You Will:Design and maintain automation systems for provisioning and managing server fleets.Develop tools to monitor server health, performance, and lifecycle events.Collaborate with teams across clusters, networking, and infrastructure.Partner with external operators to uphold high-quality standards.Identify and resolve performance bottlenecks and inefficiencies.Continuously enhance automation to minimize manual tasks.

Join Astranis as a Senior Software Engineer specializing in Hardware Testing, where you'll play a crucial role in developing and enhancing our cutting-edge satellite technology. You will work alongside a talented team focused on creating reliable and innovative hardware solutions that redefine connectivity globally.Your expertise will contribute to our mission of delivering affordable internet access to underserved regions, making a real difference in people's lives. If you are passionate about technology and eager to tackle challenging problems, this opportunity is perfect for you!

Astranis is at the forefront of satellite technology, pioneering advanced satellites for high orbits that extend humanity's reach into the solar system. Our satellites deliver dedicated, secure networks to a diverse clientele, including large enterprises, sovereign governments, and the US military. With five satellites currently in orbit and numerous launches on the horizon, we are addressing a backlog exceeding $1 billion in commercial contracts.Astranis is the trusted satellite communications partner for clients demanding high uptime, robust data security, network visibility, and tailored solutions. We have secured over $750 million in funding from leading investors such as Andreessen Horowitz, Blackrock, and Fidelity, and our team of 450 engineers and entrepreneurs operates from our expansive 153,000 sq. ft. headquarters in Northern California.Senior Hardware/Production Test Software EngineerWe are in search of an experienced and driven Hardware/Software Test Engineer to join our dynamic team. In this pivotal role, you will design high-level software architecture to facilitate vehicle integration and testing operations. You will collaborate with various engineering teams to develop and implement effective test plans and create software for automated testing at both component and integrated levels. Furthermore, you will refine specifications from electrical engineers to validate critical flight components and support all stages of development from proposal to successful testing and flight. Your contributions will also include implementing ground control and telemetry software and strengthening our team through recruitment and hiring initiatives.

About the TeamAt OpenAI, our Hardware organization is at the forefront of developing silicon and system-level solutions tailored specifically for the demanding requirements of advanced AI workloads. Our team is dedicated to pioneering the next generation of AI-native silicon, collaborating intimately with software and research partners to design hardware that is tightly integrated with AI models. Beyond delivering high-quality silicon for OpenAI's supercomputing infrastructure, we innovate by creating custom design tools and methodologies that propel hardware solutions optimized for AI.About the RoleIn this pivotal role, you will enhance the tooling ecosystem that hardware engineers depend on daily, encompassing hardware compilers, IR transformations, simulation, debugging, and automation infrastructure. Your contributions will bridge software engineering, compiler concepts, and practical hardware workflows, significantly influencing the speed and efficiency of designing next-generation AI systems. Collaborating closely with architects, RTL designers, and verification engineers, you will translate real engineering challenges into sustainable, scalable tooling solutions.Key ResponsibilitiesDevelop and enhance software tools to increase the efficiency of hardware teams: compilation, IR transformations, RTL generation, simulation, debugging, and automation.Extend and integrate hardware compiler stacks (including frontends, IR passes, lowering, scheduling, and code generation to Verilog/SystemVerilog) and connect these with actual design workflows.Enhance developer experience and system reliability: focus on reproducible builds, improved error messaging, quicker iteration cycles, and robust CI and regression infrastructures.Collaborate with designers and verification engineers to transform identified pain points into effective solutions.Engage with RTL as required: analyze and interpret Verilog/SystemVerilog to troubleshoot issues, validate tool outputs, and enhance debuggability.Be prepared to delve deeply into the stack when necessary, including gate-level perspectives, synthesis outcomes, and implementation artifacts.Support PPA optimization efforts by creating analysis and automation around area, timing, and power trade-offs, while improving tools that influence these aspects.Ideal Candidate ProfileProven experience in developing and maintaining software (through projects, internships, research, open-source contributions, or similar).

About Retell AIAt Retell AI, we are pioneering the future of call centers through innovative voice AI technology. Our cutting-edge solutions are transforming how companies engage with customers.In just 18 months since our inception, we've empowered thousands of businesses with our AI voice agents that efficiently manage sales, support, and logistics calls, significantly reducing the need for large teams of human agents. Supported by industry-leading investors including Y Combinator and Alt Capital, we've grown our annual recurring revenue from $5M to an impressive $36M while expanding our team from 5 to 20 talented individuals since 2025.Our ambitious vision for 2026 is to develop a state-of-the-art customer experience platform where entire contact centers are driven by AI. Unlike basic automation requiring constant human oversight, we’re engineering intelligent AI “workers” capable of serving as frontline agents, quality assurance analysts, and managerial roles, all while optimizing customer interactions continuously.We are rapidly expanding and seeking driven builders who thrive on solving complex technical challenges, act decisively, and wish to make a tangible impact in one of the fastest-growing voice AI startups.Join us in shaping the future!Recognized as a top 50 AI application in the a16z list: https://tinyurl.com/5853dt2xRanked #4 in Brex's Fast-Growing Software Vendors of 2025: https://www.brex.com/journal/brex-benchmark-december-2025Featured among the top startups on: https://leanaileaderboard.com/

Who We AreSamsara (NYSE: IOT) is at the forefront of the Connected Operations™ Cloud, a transformative platform that empowers businesses reliant on physical operations to tap into Internet of Things (IoT) data. Our aim is to provide actionable insights that enhance safety, efficiency, and sustainability across vital industries such as agriculture, construction, transportation, and manufacturing. By digitally transforming these sectors, which represent over 40% of global GDP, we are contributing to a more efficient and sustainable economy.Joining Samsara means being part of a team that is defining the future of physical operations. You will engage in cutting-edge solutions, including Video-Based Safety, Vehicle Telematics, and Equipment Monitoring, within a supportive environment that fosters innovation and long-term impact.About the Role:We are seeking a Senior Hardware Systems Engineer to enhance our rapidly expanding product line. Your primary responsibility will involve leading the electrical engineering components of product architecture and design, grounded in comprehensive feasibility, design, and cost analyses. This encompasses critical aspects such as component selection, thermal management, and antenna design. You will leverage extensive telemetry and direct customer insights to inform and refine our product designs. Collaborating closely with Product Management, Firmware, and Hardware leadership, you will influence key engineering decisions while mentoring fellow engineers. The role will also require interaction with our US and Taiwan EE teams, as well as our Supply Chain and laboratory resources, to achieve our project goals effectively.This role is hybrid, requiring you to be in our San Francisco, CA office three days a week, with the flexibility to work remotely for two days. Travel may be necessary up to 25% of the time, and proximity to an international airport is essential. We offer relocation assistance for this position and welcome candidates from across the U.S. who are willing to relocate to the Bay Area.

About Resolve AIAt Resolve AI, we are revolutionizing the field of software engineering by addressing the burdens of software maintenance and production troubleshooting. Our cutting-edge AI Production Engineer autonomously investigates and resolves complex system issues from start to finish.Founded by Spiros Xanthos and Mayank Agarwal, who were pivotal in developing OpenTelemetry and leading Splunk Observability, our leadership team boasts a history of two successful exits to Splunk and VMware.We have secured over $150 million in funding from prestigious investors such as Lightspeed, Greylock, Unusual Ventures, and notable individuals like Jeff Dean (Chief Scientist, Google DeepMind), Thomas Dohmke (CEO, GitHub), Matt Garman (CEO, AWS), Reid Hoffman (Founder, LinkedIn), and Fei-Fei Li (Professor, Stanford).The RoleWe are seeking AI Agent Engineers who meld robust engineering expertise with AI-driven innovation, and a steadfast commitment to enhancing customer outcomes. Your role will encompass not just delivering features but also fully grasping customer challenges and implementing solutions that tangibly enhance their experiences.The most accomplished software engineers spend considerable time determining what to build, rather than merely coding. With the emergence of tools like Claude Code and Cursor, this balance is shifting, and we believe this trend is beneficial.This position transcends traditional software engineering. It acknowledges that impactful engineering work today resides at the crossroads of advanced technical execution, deep customer understanding, and thorough evaluation of effective solutions.What You'll DoChampion customer success from start to finish. Collaborate closely with customers, design partners, and internal teams to outline technical requirements, define success metrics, and establish delivery timelines — and then take the initiative to build and launch the solutions.Develop meaningful product features. Design and implement features across the entire technology stack, focusing on addressing real-world problems encountered in production rather than abstract concepts.Seamlessly integrate with customer environments. Dive deep into understanding customer systems and ensure our solutions fit perfectly within their workflows.

fractional-ai is looking for a Senior or Staff Software Engineer to join the San Francisco office. This position centers on building advanced AI solutions with a team that values both technical depth and collaboration. Role overview This role focuses on designing and developing AI-driven systems. The work involves solving technical challenges and contributing to projects that push the boundaries of what AI can achieve. Collaboration with other engineers and stakeholders is a key part of daily responsibilities. Who will thrive Experienced engineers with a strong background in software development Those who enjoy working on complex technical problems Individuals who value teamwork and open communication Location This position is based in the San Francisco office.

The Trade Desk is a leading global technology company dedicated to fostering a better, more open internet for everyone through principled, intelligent advertising. With the capability to handle over 1 trillion queries daily, our platform operates at an unparalleled scale. We pride ourselves on our award-winning culture, built on the foundations of trust, ownership, empathy, and collaboration. We appreciate the unique experiences and perspectives that every individual brings to The Trade Desk, and we are committed to creating inclusive spaces where everyone can express their authentic selves at work. If you are passionate about solving complex problems at scale and are eager to join a dynamic, globally-connected team where your contributions will significantly impact the media ecosystem, we invite you to explore why Fortune magazine consistently ranks The Trade Desk among the top small to medium-sized workplaces worldwide. As a Senior Software Engineer, you will have end-to-end ownership, allowing you to engage in various facets of designing, building, and delivering data-centric products for our stakeholders. At The Trade Desk, we focus on constructing the back-end infrastructure of our platform with an unwavering commitment to quality at scale. Whether developing components for our client-facing applications, crafting internal custom solutions for our teams, or building model pipelines for bidding optimizations, we ensure that the infrastructure, development processes, and tools empower us to execute efficiently. Our systems operate continuously, serving global traffic, and we collaborate in a highly cooperative environment while leveraging a diverse array of technologies. Our back-end developers tackle algorithmic, optimization, and scalability challenges across all our initiatives.

fractional-ai is hiring a Software Engineer to join the team onsite in San Francisco. This role centers on building and improving technology that advances artificial intelligence. Role overview As a Software Engineer, you will work closely with others to develop and support projects that drive the company’s AI initiatives forward. The work involves collaborating with colleagues and contributing technical solutions in a team setting. What you will do Develop software for AI-driven projects Collaborate with team members in the San Francisco office Contribute ideas and technical expertise to ongoing initiatives Requirements Interest in technology and artificial intelligence Ability to work onsite in San Francisco Strong motivation to learn and contribute to team projects

About Our TeamAt OpenAI, our Hardware team specializes in developing cutting-edge silicon and system-level solutions tailored to meet the rigorous demands of advanced AI applications. We are at the forefront of creating the next generation of AI-native silicon and collaborate closely with our software and research partners to ensure our hardware is seamlessly integrated with AI models. Our mission extends beyond just delivering production-grade silicon for OpenAI’s supercomputing infrastructure; we are also dedicated to innovating custom design tools and methodologies that enhance hardware optimized for AI.About the PositionWe are seeking a highly skilled Mechanical Engineer with a minimum of 7 years of experience in the design of IT hardware, encompassing everything from chip/package to system levels. In this role, you will collaborate with a team of experts across thermal, mechanical, electrical, software, and systems engineering to support the design, analysis, and validation of mechanical and thermal systems that guarantee the reliability, efficiency, and longevity of critical hardware. A strong analytical mindset, hands-on testing experience, and the ability to thrive in a fast-paced, multidisciplinary environment are essential for success in this role.This position is based in San Francisco, CA, and follows a hybrid work model, requiring 3 days in the office per week. We also offer relocation assistance for new hires.Key ResponsibilitiesLead mechanical designs for AI supercomputer products within data center applications.Collaborate with cross-functional teams to design and enhance thermal solutions for data center hardware, including chips, power modules, and system-level cooling architectures.Integrate thermal management strategies into hardware designs from concept through to mass production.Design and validate mechanical systems such as chassis, enclosures, and cooling systems while ensuring compliance with performance and reliability standards.Conduct 3D modeling, finite element analysis (FEA), tolerance analysis, and prototyping to ensure manufacturability and adherence to stringent quality requirements.Perform mechanical testing, including vibration, shock, and thermal cycling, to ensure long-term reliability under extreme operating conditions.Identify and assess new technologies and methodologies to enhance mechanical and thermal performance in product designs, contributing expertise in mechanical design to new product development initiatives.

Responsibilities:Develop Our Product. Take ownership of software features that enhance our AI platform, empowering private market investors to analyze deals swiftly and accurately. This role requires you to actively engage in coding and delivering essential platform components from the ground up.Ensure Quality and Excellence. Establish and maintain coding standards, architectural guidelines, and review procedures; mentor fellow engineers. Co-cultivate a culture centered on practical, reliable, and test-driven development that swiftly meets business requirements.Scale for Growth. Assist in monitoring and scaling the architecture of our platform and its infrastructure.Collaborate Across Functions. Engage closely with product, security, and go-to-market teams to translate our strategic roadmap into actionable features and deliverables.

Role overview MidiHealth is hiring a Staff Software Engineer - AI Engineer for a hybrid role in the San Francisco Bay Area. The position focuses on building and improving AI-powered solutions that contribute to better healthcare outcomes. What you will do Collaborate with cross-functional teams to design and implement AI-driven systems for healthcare. Develop scalable architectures and write efficient algorithms tailored to healthcare applications. Uphold strong software quality standards throughout the development lifecycle. Location This position is hybrid, with work based in the SF Bay Area.

With support from prominent Silicon Valley investors, Peregrine Technologies empowers public safety organizations, state and local governments, federal agencies, and private sector entities to tackle societal challenges with unparalleled speed and precision. Our AI-driven platform transforms isolated and disparate data into actionable intelligence, rapidly presenting critical information that enables improved decision-making and outcomes. Currently, Peregrine serves hundreds of clients across over 30 states and two countries, impacting more than 125 million individuals, as we broaden our reach into enterprise markets and international territories.TeamOur engineering team is deeply committed to the idea that empathy enhances our solutions. Understanding how users interact with our products is fundamental to our approach. Engineers have the unique opportunity to collaborate closely with our onsite team to grasp the diverse use cases that Peregrine addresses.We cherish both ownership and teamwork; you will be fully accountable for significant features while working hand-in-hand with fellow engineers to ensure successful delivery. We believe that humility and empathy are critical for crafting effective solutions, and you will engage directly with our deployment team and users as we refine our offerings to meet their needs. Ingenuity and perseverance are vital in realizing our vision.RoleAs part of our new AI team, you will play a key role in delivering unique value to our clients. This team is responsible for designing powerful and intuitive user experiences powered by generative AI. You will explore entirely new interaction methods for users—whether through natural language commands or by enabling AI agents to manage complex tasks on their behalf. Your contributions will shape impactful AI-driven features that assist customers in solving real-world challenges more efficiently.Your work will encompass a variety of intricate challenges, including scaling our platform to process terabytes of data from multiple sources, efficiently querying and alerting users about this data in real-time, and optimizing search algorithms for swift result delivery.While our technology stack is continuously evolving, it is built on a foundation that includes Python, Django, Celery, Airflow, and Kafka for the backend; React, Redux, and Mapbox for the frontend; PostgreSQL and Elasticsearch for data storage; machine learning models hosted in Bedrock and Sagemaker; and utilizing AWS, Pulumi, Terraform, and Kubernetes for our infrastructure.

About UsXOXO is an innovative research lab dedicated to crafting intelligent interfaces that enhance everyday life. Our stealth team, composed of passionate engineers, designers, and researchers, is focused on solving unique challenges that go beyond the workplace.With recent advancements in infrastructure, architecture, and model layers, we are actively seeking skilled builders to create the application layer that will actualize our visionary concepts.About the RoleWe are on the lookout for a proficient iOS engineer to lead the development of XOXO’s consumer app, featuring a pioneering interface for intelligence. This position calls for a robust engineer capable of managing the entire mobile surface area, from architecture and performance to refining a visually appealing design system that ensures intentional user interactions.A specific background is not mandatory; what truly matters is your passion for ownership: you take charge, work swiftly without compromising quality, and aspire to create a mobile product that redefines craftsmanship and performance standards.What You’ll DoDesign and launch the initial versions of our React Native app, transitioning it from concept to production.Convert a visually rich design system into reusable components, motions, and interaction patterns with seamless performance.Develop new product interfaces that seamlessly integrate modern AI/ML capabilities in a mobile-friendly manner.Enhance app performance, focusing on rendering, startup, memory consumption, battery usage, and perceived speed.Establish high standards for mobile engineering quality (including testing, monitoring, and release management) while collaborating with various teams to ensure successful delivery.

About the TeamThe Scaling team at OpenAI forms the architectural and engineering foundation of our infrastructure. We innovate and implement advanced systems that facilitate the deployment and operation of next-generation AI models. Our responsibilities encompass system software, networking, platform architecture, fleet-level monitoring, and performance enhancement.About the RoleWe are seeking a skilled software engineer proficient in transforming early-stage, sometimes chaotic, pre-production hardware into stable, operational systems. You will be pivotal in bootstrapping, imaging, integrating with the Kubernetes control plane, and ensuring observability. Your role will bridge early hardware bring-up, provisioning automation, fleet and cluster management, and integration with lab or cloud services—effectively converting new SKUs into usable capacity for our internal stakeholders.Key ResponsibilitiesManage the comprehensive bring-up and bootstrapping process for new systems and compute nodes, transitioning from bare metal or early access in lab or production/cloud settings to schedulable fleet capacity, including image building, user-data/configuration, cluster joining, and readiness gates.Develop and uphold top-tier golden image and provisioning workflows across lab and production environments, collaborating with partner-provided base images while ensuring OS/version compatibility.Collaborate with partner teams to integrate nodes into our fleet infrastructure and Infrastructure as Code (IaC) pipelines (Terraform, Chef, etc.), guaranteeing that cloud resources align seamlessly with our internal lifecycle expectations.Work closely with scheduling and platform owners to ensure new hardware is accessible and properly scheduled, addressing pool definitions, network connectivity, routing, admission controls, and platform-specific requirements.Ensure registration and inventory accuracy, providing hands-on support to track nodes and their metadata from end to end.Partner with teams to establish baseline health and telemetry monitoring for bring-up, including critical health signals, pass/fail assessments, and automated reporting for initial ramp decisions.Troubleshoot issues across various layers, including PXE/boot-loader, UEFI/BIOS, BMC, OS bring-up, NIC/network accessibility, kubelet/control-plane connectivity, storage limitations, and early lab/rack scenarios.