Senior Infrastructure Engineer at gumloop | San Francisco

Join Sphere, where we leverage AI technology to redefine international trade law.At Sphere, we empower companies like Lovable, Eleven Labs, Replit, and Runway AI to seamlessly automate their sales tax, VAT, and GST compliance:Experience rapid growth with us (30%+ month-over-month revenue increase) as we collaborate with some of the fastest-growing tech companies globally.After two years of dedicated effort, we have integrated local compliance solutions into over 100 tax authorities worldwide, a feat unmatched by any other vendor.We are developing the first AI-native tax engine, forming the backbone of a comprehensive cross-border compliance platform.Our funding partners include industry leaders such as a16z, Y Combinator, 20vc, and Felicis Ventures.As we scale to accommodate millions of global transactions, building a robust infrastructure for transaction synchronization and real-time tax calculations is crucial.This role focuses on ensuring availability, resilience, and speed within mission-critical billing flows for leading companies.Why This Role is a Major Opportunity: Enormous Total Addressable Market: Every business requires compliance solutions. Favorable Market Trends: As businesses expand globally, the urgency for compliance solutions increases. AI-Driven Advantages: Our AI-native tax engine allows us to scale beyond traditional limitations. Multi-Product Expansion: Indirect tax is just our starting point; we are building a comprehensive solution for all revenue-based compliance needs.Your Responsibilities:In the initial weeks:Identify innovative solutions to enhance Sphere's infrastructure...

ABOUT SPHERESphere is revolutionizing trade compliance with cutting-edge AI technology. Our innovative system, TRAM, autonomously analyzes and interprets global trade laws, ensuring reliable compliance determinations across various jurisdictions. We manage the full compliance lifecycle—from calculation and registration to filing and remittance—with millisecond latency and zero downtime.At Sphere, we are proud to be backed by prominent investors such as a16z and Y Combinator, and we've achieved over 30% month-over-month growth. Our impressive client roster includes emerging leaders like ElevenLabs, Replit, Deel, and Runway. We operate with a small, dedicated team in our San Francisco headquarters, where every member has ownership over significant domains of our platform.THE ROLEWe are seeking experienced Senior Full Stack Engineers to spearhead the development of new product lines, including input tax, withholding tax, e-invoicing, and tariffs. Your contributions will be pivotal in scaling our operations and directly influencing our annual recurring revenue (ARR).WHAT YOU'LL DOWithin weeks:Deliver critical features that clients rely on daily, such as filing infrastructure.Take ownership of a feature and drive measurable outcomes.Collaborate with customers like Eleven Labs, Lovable, and Deel to enhance key components of our platform, aiming to improve filing generation and submission speeds.Within months:Lead the end-to-end development of new product lines, furthering our AI-driven compliance platform.Mentor junior engineers and foster a collaborative team environment.

ABOUT SPHEREAt Sphere, we are redefining trade infrastructure by addressing one of its most complex challenges: compliance. Our innovative AI system, TRAM, simplifies the intricacies of global trade law, providing rapid and precise compliance determinations that outpace traditional methods.With significant backing from a16z and Y Combinator, we have achieved remarkable growth, serving diverse clients such as ElevenLabs and Replit. Join our small yet impactful team in San Francisco, where every member plays a pivotal role in our mission to streamline trade compliance.Startup Growth: Experience rapid expansion with 30%+ month-over-month growth and a $21M Series A funding.Dynamic Team Environment: Work closely with our Founder and CEO, where your contributions significantly influence our trajectory.Complex Challenges: Engage with evolving compliance landscapes, tackling input tax, e-invoicing, and more.

About GigaGiga has recently secured $61 million in Series A funding and is already collaborating with prominent clients, including DoorDash. We are on a mission to revolutionize customer experience by developing advanced AI agents capable of understanding emotions, resolving issues instantaneously, and scaling solutions across the globe's largest enterprises.This pivotal moment in our journey reflects our ambition to establish ourselves as the leading AI platform for enterprise automation, driven by our cutting-edge voice superintelligence. To realize this vision, we are seeking exceptional engineers to join our team.Our work impacts millions of lives daily, providing engineers with the autonomy to make a genuine difference. This role offers a unique chance to be part of a talented founding team, achieve commercial success, and contribute to a company with the potential to become a generational leader.For more insights into Giga, check out:Voice AI startup Giga raises $61M Series ADoorDash and Giga PartnershipJoin us and help build AI agents that are trusted by the world’s leading B2C companies, including DoorDash, as they navigate complex support and operational workflows across voice, chat, and email channels.The RoleWe are in search of a skilled infrastructure engineer to develop the foundational platform that powers our AI agents. Your primary users will be fellow engineers; your mission will be to design systems, tools, and abstractions that enhance productivity and ensure the reliability of our platform.This position goes beyond traditional DevOps or SRE roles. You will be writing application code with a specific focus on foundational layers such as deployment systems, observability, data infrastructure, and the internal tools that enable swift, efficient operations without compromising stability.What You'll Work OnHere are a few key projects you will be involved with:Controlled deployments: Implementing staged rollout systems with traffic scaling, scheduling, and pass rate thresholds to protect production environments.Observability: Developing instrumentation, logging, and monitoring frameworks that provide insights into production performance.Data infrastructure: Creating robust data pipelines and storage solutions to support our operations.

About Atomic SemiAtomic Semi is pioneering the development of a compact and rapid semiconductor fabrication facility.Utilizing current technologies and innovative simplifications, we aim to create our own tools, enabling swift iterations and continuous enhancements.Our team comprises exceptional, hands-on engineers across various disciplines—mechanical, electrical, hardware, computer, and process engineering. We are committed to owning our entire operational stack, from atomic structures to architectural designs. Our optimistic outlook drives us to push the boundaries of technology.We believe that smaller, faster solutions are superior, and that building our own tools is the best path forward.Equipped with advanced 3D printers, an extensive range of microscopes, e-beam writers, and general fabrication tools, we are ready to invent whatever is necessary throughout this journey.Founded by Sam Zeloof and Jim Keller, our vision is backed by Sam’s garage-chip manufacturing experience and Jim’s four decades of leadership in the semiconductor industry.About the RoleAs a Backend Infrastructure Engineer, you will develop the core systems that drive our fabrication products, with a focus on backend architecture, data models, and hardware integrations.

ABOUT SPHEREAt Sphere, we are revolutionizing trade compliance by reducing transaction costs and expanding market access. Our innovative AI system, TRAM, processes global trade laws with unmatched precision and speed, enabling compliance determinations that surpass human capabilities. We manage the entire compliance lifecycle — from calculations to remittances — with lightning-fast efficiency and zero downtime.With backing from prestigious investors like a16z and Y Combinator, we have raised $21 million in Series A funding and are experiencing over 30% month-over-month growth. Our clientele includes industry leaders such as ElevenLabs, Replit, Deel, Runway, and Lovable.Join our small, yet impactful team in San Francisco, where each member owns significant responsibilities that would typically require large teams in bigger organizations. We are moving toward tackling the complexities of input tax, withholding, e-invoicing, and tariffs, anticipating billions of transactions in the near future.

About CasaAt Casa, we believe that homes are among life’s most cherished assets, yet the experience of homeownership can often be frustrating. We are on a mission to revolutionize this experience by creating a next-generation personal property management solution tailored for single-family homes, ensuring that owning a home becomes a delight.Founded by early visionaries from Uber, CloudKitchens, and Levels, Casa is proud to be supported by a remarkable group of leading venture capital firms and angel investors. Our service is already live and delivering value to paying members.About the RoleWe are seeking a pioneering Senior Backend Engineer to join our dynamic team. In this role, you will be instrumental in designing, developing, and deploying robust backend systems that provide exceptional value to our members.You will collaborate closely with our founders, fellow engineers, and designers to craft innovative and impactful products. Your contributions will be vital in shaping our core systems and defining the culture of our founding team.Key ResponsibilitiesArchitect and develop scalable, secure, and reliable backend systems.Design and implement APIs that enhance our iOS applications and other client interfaces.Optimize the performance and scalability of our services to accommodate an expanding member base and increasing data volume.Stay updated with the latest advancements in backend technologies and cloud infrastructure, integrating new methodologies as suitable.Mentor a growing engineering team through code reviews and constructive feedback to uphold high-quality standards.About YouYou are passionate about building robust systems. You possess a deep understanding of backend architecture, API design, and database management, and are eager to construct systems that can scale with our increasing member base.You are excited to be a founding engineer at an early-stage startup, ready to contribute to the structure and systems being established, while also shaping the company culture.You thrive on building. You embrace the challenges and opportunities for growth that come with joining an early-stage company, and you excel in a fast-paced, evolving environment.You think and act decisively. Your proactive mindset will contribute significantly to our mission.

Join Point as a founding Senior Backend Engineer and be part of a team creating a modern and aspirational banking experience. We are dedicated to enhancing everyday debit cards with exciting rewards and benefits, setting a new standard in banking.Discover more about Point's innovative team and dynamic culture here.

Location: San Francisco, CAType: Full-time, on-siteOverview: As the demand for AI agents surges, we are on a rapid hiring spree to meet this challenge. At AgentMail, we are innovating in a space where the solutions are still being discovered; we focus on creating systems that empower agents as essential components of the internet. If you thrive in building products from the ground up, we want to hear from you.AgentMail is developing an API that provides dedicated inboxes for AI agents, serving as their primary identity and communication hub. This isn't just AI-enhanced email; it's email tailored for AI.We are searching for a foundational engineer with robust backend and infrastructure skills to create the essential tools that agents will utilize for communication, authentication, and real-world operations. This role is perfect for someone who enjoys working with systems: APIs, distributed architecture, reliability, and developer tools.Why Join Us?Exceptional Team: Our team comprises industry experts with backgrounds in quantitative analysis, software engineering, and private equity, featuring talent from companies like Optiver, NVIDIA, Amazon, Modern Treasury, and KKR.Rapid Growth: Our user base has doubled every two weeks since January, and we anticipate this growth to continue. With agents soon surpassing human numbers, we expect significant market changes.Unique Position: We are the exclusive identity provider for AI agents, similar to how Gmail serves human users.Key ResponsibilitiesLead and mentor a team of 4-6 engineers.Design user-friendly APIs and abstractions for humans and AI agents alike.Develop high-performance, low-latency systems with AI agents as the end-users.Engage directly with our core infrastructure, managing the processing of hundreds of thousands of emails daily.Innovate at the intersection of advanced AI capabilities and traditional email systems.Oversee projects from inception through to production deployment.Produce clean, maintainable code along with comprehensive technical documentation.Actively gather and respond to customer feedback to drive improvements and refinements.

About UsScribe is a dynamic workplace where talented individuals come together to achieve remarkable professional milestones. With over 94% of the Fortune 500 relying on Scribe to enhance their operations, our Workflow AI platform effortlessly captures and optimizes workflows, enabling teams to work smarter, faster, and with greater consistency.Since our inception in 2019, we have experienced rapid growth, amassing more than 5 million users across 600,000 businesses. Headquartered in San Francisco, we have been recognized as a LinkedIn Top Startup, valued at over $1 billion, and supported by prominent investors. Join us as we transform the way work is accomplished.Our Work CultureWe are passionate builders striving to perfect our crafts. We deeply value our colleagues and are committed to achieving success together. We adhere to the following principles:Accelerate ImpactRaise the BarEmpower Our UsersClarity is KindRapid LearningOne Team, One DreamRole OverviewWe are on the lookout for a Senior Backend Engineer to become a vital member of our Core Engineering Team, which drives some of the key functionalities at Scribe, such as document viewing and editing, content embedding and exporting, and supporting essential integrations. Millions of users depend on these workflows daily.In this position, you will take the lead on influential projects — from enhancing critical document features to developing new greenfield systems — while collaborating across the technology stack to deliver exceptional product experiences. As a backend engineer, you will deepen our systems, engage in technical discussions, and elevate the standard of engineering excellence within the team.Your ResponsibilitiesDevelop and deploy backend features within our Django monolith, covering core document workflows (viewing, editing, embeds, exports) as well as innovative greenfield projects that broaden Scribe's capabilities.Enhance performance and reliability by fine-tuning database queries, endpoints, and caching layers for critical user workflows.Collaborate with product managers, designers, and frontend engineers to create intuitive and dependable experiences at scale.Contribute to the architecture and design of our systems to improve overall efficiency and maintainability.

Join us on-site in the vibrant Dogpatch neighborhood of San Francisco as a Senior Backend Engineer.About GigaGiga, a pioneering voice AI startup, has successfully secured a $61M Series A funding and boasts an impressive roster of clients including DoorDash. We are dedicated to revolutionizing the customer experience through real-time AI agents capable of understanding emotions and resolving issues instantly, while being scalable across the globe's largest enterprises.This is a pivotal moment for our company as we aim to expand our horizons. Our ambition is to position Giga as the premier AI platform for enterprise automation, driven by our cutting-edge voice superintelligence. To realize this vision, we are seeking exceptional engineers to join our team.Our engineers are empowered to make significant impacts, influencing the daily experiences of millions. This unique opportunity allows you to work alongside visionary founders, contribute to a commercially successful venture, and help shape a generational company. Here are some highlights about us:Voice AI startup Giga raises $61M Series ADoorDash and Giga PartnershipGiga is trusted by leading B2C companies around the world to manage their most complex support and operational workflows across various communication channels including voice, chat, and email. If this excites you, we encourage you to apply!The RoleWe are searching for innovative backend engineers to develop the infrastructure and systems that power our AI agents. You will engage with a variety of technologies from data pipelines and analytics to real-time agent systems, delivering features that have a direct impact on our customers' operations.This position grants you the freedom to own challenges from start to finish—identifying the optimal approach, constructing solutions, and refining them based on your findings.What You'll Work OnHere are a few key projects from our current roadmap:Analytics overhaul: Transitioning our analytics service to ClickHouse and optimizing it for the next phase of growth.Hallucination detection: Enhancing our detection systems with the aim of minimizing hallucination occurrences.Browser agent utilization: Scaling and stabilizing our systems to ensure robust performance.

Join Revi as a Senior Backend Engineer and Shape the Future of Retail! At Revi, we're revolutionizing the retail landscape by merging the physical and digital worlds. As pioneers in the emergence of Web 3.0, we are transforming brick-and-mortar experiences into seamless digital interactions. With over three decades of evolution in web technology, we are on the brink of a new era where physical stores can harness the power of the internet to create unparalleled customer experiences.Our mission is to empower businesses with a state-of-the-art in-store digital platform that fosters lasting customer relationships. Our beautifully designed self-ordering system enables consumers to buy, pay, and earn rewards effortlessly. With fresh Series A funding of $14.5 million from top-tier Silicon Valley investors, we are poised to seize a multi-billion dollar market opportunity.Why Join Us Now? This is a pivotal moment for Revi. With our AI-driven in-store platform already live with growing restaurant chains, we are experiencing strong product-market fit and customer demand for new features. This is your chance to make a significant impact on our technical direction while building on a foundation of proven success.

Senior Backend EngineerJoin LiteLLM, the leading AI Gateway trusted by industry giants including Adobe, Netflix, and NASA. Our platform empowers developers with secure and reliable access to Large Language Models (LLMs) and related services. We are currently seeking a dedicated Senior Backend Engineer to contribute to the development of robust guardrails and observability tools at scale.About The RoleIn this role, you'll take ownership of our guardrail and logging implementations. You will oversee backend code to ensure all guardrail interactions are logged accurately, user errors are communicated effectively, and that our observability tools function seamlessly under high traffic conditions. Your meticulous attention to detail regarding latency metrics, logging traceability, and backend guardrail registration will significantly bolster user confidence in our security and compliance capabilities.ResponsibilitiesDevelop and enhance our product to maximize performance, reliability, and ongoing improvements.Ensure guardrail and policy enforcement calls (e.g., applyguardrail) are accurately logged and traceable through our SpendLogs and relevant database tables.Design and implement CPU-level guardrails to mitigate common attacks on LLM APIs, MCP servers, and Agents.Identify and resolve silent failure points in guardrail creation, registration, and policy application—ensuring robust error handling and transparency for end users.Collaborate with observability tools such as Datadog, Splunk, Prometheus, and OpenTelemetry to maintain accurate, configurable, and effective monitoring and logging for backend systems.Enhance observability integrations to manage over 1 billion requests per month with minimal latency and no memory leaks due to Prometheus metrics cardinality.Work cross-functionally on backend engineering priorities including performance, reliability, and security enhancements.What We’re Looking ForBachelor’s or Master’s degree in Computer Science or a related field.4+ years of experience with Python and backend frameworks (e.g., FastAPI, Flask).Strong understanding of logging best practices, error handling, and secure backend development.Familiarity with monitoring, logging, or metrics tools.

We are seeking a highly skilled Senior Infrastructure Engineer to join our dynamic team at Bitgo. In this pivotal role, you will design, implement, and maintain our infrastructure systems, ensuring optimal performance and security. You will collaborate with cross-functional teams to develop innovative solutions and enhance our operational efficiency.Your expertise will be crucial in managing complex infrastructure environments and leveraging automation to streamline processes. If you are passionate about infrastructure engineering and are looking to make a significant impact in a fast-paced, cutting-edge environment, we want to hear from you!

About UsOur mission is to revolutionize language learning.Learning a new language can transform lives by providing access to diverse cultures, career opportunities, and communities. With two billion people globally striving to learn languages, the most effective method—one-on-one tutoring—remains difficult to access at scale and has not evolved significantly over the years. Speak is developing an AI-powered, human-like tutor that fits in your pocket, offering a conversation-first approach that allows learners to practice speaking, receive immediate feedback, and progress through thoughtfully designed lessons. This results in a comprehensive journey from novice to confident speaker across multiple languages.Since our launch in South Korea in 2019, Speak has emerged as the leading language learning app, now available to learners in various markets and over 15 languages. As one of the foremost AI companies globally, we have secured over $150 million in venture capital from notable investors such as OpenAI, Accel, Founders Fund, and Khosla Ventures, with a diverse team spread across San Francisco, Seoul, Tokyo, Taipei, and Ljubljana.About This RoleWe are seeking a Senior Backend Engineer, with full-stack capabilities, to help create innovative AI-driven product experiences. The ideal candidate should have experience collaborating closely with product, design, and machine learning teams, alongside a proven track record in developing polished consumer applications. This role is pivotal in shaping our latest products focused on programmatic, conversational language learning and will significantly impact the future direction of our company.Your ResponsibilitiesCrafting innovative AI-driven product experiences and user interfaces for the web.Full-stack engineering with a primary focus on designing scalable backend systems.Troubleshooting complex streaming challenges.Taking ownership of the complete development cycle of features from ideation to production.Writing code efficiently, shipping frequently, and making a substantial impact on our business by facilitating the scaling of our content.Your Profile5+ years of industry experience as a Backend Engineer, ideally within a fast-paced startup environment.Bonus: Experience on an app that has reached over 1 million users.Exceptional problem-solving and communication skills, along with the ability to work effectively in a collaborative environment.

About CasapCasap is an innovative Series A startup backed by over $30M in funding from renowned investors such as Emergence, Lightspeed, and Primary Ventures. Located in the vibrant tech hub of San Francisco, our team consists of experienced product leaders from industry giants like Robinhood and Chime. Our mission is to revolutionize banking operations by automating disputes and combating friendly fraud. Our solutions have garnered love and appreciation from everyday users and major financial institutions alike.We are currently seeking skilled Backend Engineers to join our team in San Francisco, eager to enhance the banking experience with our rapidly growing product that sits at the cutting edge of automation and Artificial Intelligence.

About UsAt Amari AI, we are transforming the logistics industry by replacing outdated manual workflows with intelligent AI agents. Our cutting-edge technology collaborates with human operators, automating complex, document-heavy processes to enable faster, more accurate shipment processing.Having surpassed the initial development phase, we have successfully achieved product-market fit and are experiencing exceptional growth, with over 100% month-over-month revenue increase. With $5 million raised from notable investors including First Round Capital and Pear VC, we are expanding our platform's capabilities. Our highly skilled team is composed of experts from leading tech companies such as Google, LinkedIn, and Salesforce, as well as prestigious academic institutions and AI research facilities.The RoleIn the capacity of Senior Backend Engineer at Amari AI, you will play a pivotal role in shaping the core data infrastructure that drives our AI-powered logistics platform. This position offers substantial ownership and autonomy, allowing you to design and scale systems responsible for ingesting, processing, and delivering real-time logistics data across various AI components, including pipelines, queues, databases, and search layers. Your technical leadership will significantly influence product reliability and performance from the outset.What You’ll DoDesign and scale distributed backend systems - including queue pipelines, service boundary definitions, and robust failure management strategies such as retry mechanisms, circuit breakers, and graceful degradation.Manage database design and reliability - focusing on schema design, indexing strategies, and query optimization tailored to specific use cases, along with data pipelines that maintain synchronization across systems at scale.Develop AI-driven search infrastructure for real-time logistics lookups and enhanced AI features.Provide technical leadership in a dynamic startup environment - establishing engineering standards, collaborating closely with the founders on strategic roadmaps, and mentoring future backend engineers.Who We're Looking For5–8 years of professional experience in backend software engineering, preferably in high-growth startups or large-scale production environments.Proven track record of end-to-end ownership of backend systems in fast-paced, ambiguous settings.Demonstrated capability in making informed architectural decisions under time constraints, with flexibility to adapt as requirements evolve.

About UsAt Conversion, we're revolutionizing marketing automation with our AI-native platform designed specifically for modern software companies. The landscape of marketing today is fragmented by outdated tools and disconnected workflows. We're here to change that.Our solution empowers growth teams to seamlessly manage their go-to-market strategies from acquisition to retention, all within a single, fast, and personalized interface powered by AI.With over $28 million raised from leading investors like Abstract Ventures, True Ventures, and HOF Capital, we are rapidly scaling with a current ARR of over $5 million and supporting more than 4,000 customers.Join our dynamic team of high achievers in San Francisco. If you're passionate about crafting innovative, product-led marketing solutions and want to collaborate with world-class teammates, we can't wait to meet you!Over $28M in funding$0 to $6M ARR in less than 12 months, serving over 4,000 customersElite team with backgrounds from Airbnb, Palantir, Pinterest, IMC Trading, Shopify, LinkedIn, Microsoft, and moreAbout the RoleHi! I'm James, co-founder and CTO of Conversion. I want to share what we envision for our ideal candidate to join our engineering team.The challenge we face at Conversion is significant. The absence of new entrants in the marketing automation space for decades speaks to the complexity of building such platforms. Our system must reliably manage gigabytes of data syncs per customer, orchestrate intricate workflows for mission-critical processes, and handle revenue-generating form submissions while delivering high-quality emails to millions of recipients.We're seeking a backend software engineer who is:Product-focused: We value engineers who can take ownership of features, design, and implement them from start to finish. The best product managers often come from engineering backgrounds, as they can effectively assess both the benefits and costs of new features.

About MeshAt Mesh, we are on a mission to revolutionize how consumers transact with any asset. Despite the existence of trillions of dollars in tokenized assets, they remain largely untapped for daily commerce. Mesh is closing this gap by transforming crypto payments into a reliable, practical, and widely accepted method of transaction. With a robust orchestration engine paired with an intuitive consumer app, we aim to unlock liquidity on a global scale. Supported by renowned investors including PayPal Ventures, Paradigm, and Galaxy Ventures, we are laying the groundwork for the future of the global economy. Join our journey!OverviewWe are on the lookout for a skilled and seasoned Backend Engineer to become an integral part of our team. In this role, you will be pivotal in the design, development, and maintenance of our cutting-edge software solutions. Mesh operates globally, with our headquarters located in San Francisco, California. The ideal candidate will collaborate closely with our Engineering and Product teams across North America, Europe, and India.