Senior Backend Developer in San Francisco

We believe that communication belongs to everyone. TextNow is redefining how people connect by combining simplicity, intelligence, and accessibility. We’re a team of curious builders using technology to make communication more affordable and powerful for millions of users every day. As a Software Developer - Backend , you won’t just build services—you’ll shape the systems, architecture, and tooling that make them possible. At TextNow, Members of Technical Staff combine leadership and hands-on coding to enable the highest leverage opportunities possible. Being able to operate strategically, as well as diving into the lowest-level details, is a must. You’ll take technical ownership of key backend domains and work across mobile, web, and data to create faster, smarter, more reliable systems. AI and automation are at the core of how we build. You’ll use them to accelerate development, improve performance, detect and resolve issues faster, and continuously raise the bar for backend development excellence. We’re hiring Members of Technical Staff across multiple levels (intermediate/senior/staff+). Whether you’re an experienced developer looking to lead complex systems, or an early-career developer eager to grow, we’ll align your title and scope based on experience and impact. This role is about impact at scale. You’ll shape how TextNow builds and operates its backend systems—using AI and automation to make development faster, decisions smarter, and experiences more seamless for millions of users worldwide. What You'll Do Design, develop, and sustain high-performance, scalable backend services using Go microservices and modern cloud-native tooling. Lead architectural modernization and modularization to improve scalability, observability, and developer velocity. Define and own the entire lifecycle of your systems: API design, data modeling, deployment (CI/CD), live-traffic monito

#TeamNextdoor Nextdoor (NYSE: NXDR) is the essential neighborhood network. Neighbors, public agencies, and businesses use Nextdoor to connect around local information that matters in more than 350,000 neighborhoods across 11 countries. Nextdoor builds innovative technology to foster local community, share important news, and create neighborhood connections at scale. Download the app and join the neighborhood at nextdoor.com . Meet Your Future Neighbors As a Software Engineer at Nextdoor, you’ll join a focused team of developers, product managers, and designers who are passionate about using technology to cultivate a kinder world where everyone has a neighbor they can rely on. We are a small, high performing team of engineers that wear multiple hats and prioritize impact for our customers. We care about moving fast and delivering impact, without compromising on quality and reliability as guided by our Engineering Principles . You will have the opportunity to learn from your co-workers and teach them. As a team, we will make each other better and build great software. At Nextdoor, we operate in an AI-first environment and expect every team member to actively use AI tools as part of their workflow. We aren't looking for prompt engineers; we’re looking for people who use tools like Claude, Gemini, ChatGPT, and Glean to challenge their own thinking and take full ownership of AI-assisted outputs. We also offer a warm and inclusive work environment that embraces a hybrid employment model, blending an in office presence and work from home experience for our valued employees. The hiring team will go over these expectations with you if you are being considered for a role near one of our offices in San Francisco, Los Angeles, Chicago, Dallas, New York, and London. The Impact You’ll Make We believe in empowering our teams to own all aspects of bringing Nextdoor to life. As such, you’ll get the opportunity to make key contributions across our engineering stack - thi

Who We Are HP IQ is HP’s new AI innovation lab. Combining startup agility with HP’s global scale, we’re building intelligent technologies that redefine how the world works, creates, and collaborates. We’re assembling a diverse, world-class team—engineers, designers, researchers, and product minds—focused on creating an intelligent ecosystem across HP’s portfolio. Together, we’re developing intuitive, adaptive solutions that spark creativity, boost productivity, and make collaboration seamless. We create breakthrough solutions that make complex tasks feel effortless, teamwork more natural, and ideas more impactful—always with a human-centric mindset. By embedding AI advancements into every HP product and service, we’re expanding what’s possible for individuals, organisations, and the future of work. Join us as we reinvent work, so people everywhere can do their best work. About The Role As the Senior Software Engineer, Tooling and Development Infrastructure, you will play a critical role in shaping the developer productivity tools and automated testing strategy. You’ll collaborate closely with design, development, and quality teams to plan, design, and implement robust automated tools and services that ensure the quality and reliability of our AI software stack. You will be highly hands-on in your work and collaborate closely with stakeholders. This position offers a unique opportunity to influence the development of cutting-edge automation frameworks, foster a culture of quality, and contribute to the long-term success of the organization. What You Might Do Develop and implement automation frameworks and testing strategies that cover the entire software stack, from backend systems to user-facing features. Identify, evaluate, and integrate new tools that streamline development. This includes everything from code quality tools and to Infrastructure-as-Code (IaC) solutions. Lead continuous improvement efforts for our build, release, and test systems, ensuring a robust

Who We Are HP IQ is HP’s new AI innovation lab. Combining startup agility with HP’s global scale, we’re building intelligent technologies that redefine how the world works, creates, and collaborates. We’re assembling a diverse, world-class team—engineers, designers, researchers, and product minds—focused on creating an intelligent ecosystem across HP’s portfolio. Together, we’re developing intuitive, adaptive solutions that spark creativity, boost productivity, and make collaboration seamless. We create breakthrough solutions that make complex tasks feel effortless, teamwork more natural, and ideas more impactful—always with a human-centric mindset. By embedding AI advancements into every HP product and service, we’re expanding what’s possible for individuals, organisations, and the future of work. Join us as we reinvent work, so people everywhere can do their best work. About The Role As a Senior Software Engineer, Cloud Services, you will create scalable, reliable backend systems that support HP IQ's mission to transform the way people work. We value how we work as much as what we deliver. Our journey of continuous learning and evolution requires a flexible and resilient services platform that fosters innovation, experimentation, and adaptation. To enable this, we focus on designs and tools rooted in strong engineering principles like abstraction, composition, virtualization, automation, and iterative development cycles. What You Might Do Design, develop, and maintain backend services and RESTful APIs using Java and Spring Boot. Write clean, efficient, and well-tested code following established best practices. Collaborate with frontend developers, product managers, and other engineers to deliver end-to-end features. Integrate with databases and external services, ensuring performance, security, and reliability. Participate in code reviews, debugging, and performance optimization efforts. Contribute to CI/CD pipelines and support application deployment in cloud and

About the Role Sigma is transforming how businesses run by delivering a high performance platform on modern data architecture. Hence, we are growing the engineering team and looking for engineers who are excited to solve challenging problems, deliver impactful capabilities throughout our stack to build world-class technology. You will be part of a talented team of engineers with a shared mission to make data easily accessible for all users. What You Will Be Doing You will be responsible for developing elegant and responsive user experience using the latest front-end technologies. You'll own substantial pieces of the product, from design to launch Working with our product, UX design, and backend development teams, you will develop new features and technologies that make our product experience awesome and radically simplify the user experience for non-technical users You will leverage your technical expertise in front-end application development in the creation of novel visualizations for structured and unstructured data and develop new techniques for improving the performance and interactivity of the application Use modern frontend frameworks like React, GraphQL, TypeScript and Node.js Qualifications We Need 5+ years industry experience building and maintaining high-quality software An eye for great design and a passion for building products that provide a great user experience The ability to make the right trade-offs between functionality and delivery speed that supports delivering value to customers, all the while iterating based on feedback and roadmap priorities Desire to be a great teammate and have fun at work without compromising ownership towards your work Strong sense of craftsmanship, and a healthy academic curiosity to solve challenges at sigma Strong computer science fundamentals Qualifications We Want (also, skills you’ll learn!) Experience building software capabilities for analyzing large scale data web applications Prior exp

About the Role Sigma is transforming how businesses run by delivering a high performance platform on the modern data architecture. Hence, we are growing the engineering team and looking for engineers who are excited to solve challenging problems, deliver impactful capabilities throughout our stack to build world-class technology. You will be part of a talented team of engineers with a shared mission to make data easily accessible for all users. What You Will Be Doing Solve challenging problems that arise in providing an interactive experience on data warehouses for data exploration and analysis Build with modern tools and languages like Rust, Go, GraphQL, Node, and Kubernetes Build backend distributed services, new algorithms and modern API to support a cloud application Triage product or system issues and debug/track/resolve by analyzing the sources of issues Design and implement new software features to support our fast growing user base Collaborate with peers and stakeholders through design and code reviews to ensure best practices amongst available technologies Qualifications We Need 5+ years industry experience building and maintaining high-quality software Experience building and deploying robust and secure web applications in a continuous deployment environment Desire to be a great teammate and have fun at work without compromising ownership towards your work Strong sense of craftsmanship, and a healthy academic curiosity to solve challenges at sigma Strong Computer Science fundamentals Qualifications We Want (also, skills you’ll learn!) Data driven aptitude and its application to solve distributed system problems Data model design, and API development experience SQL query optimization and database internals Administered cloud service infrastructure (GCP, AWS, Azure) Prior experience working at high growth company solving technical problems to enable continued success Additional Job details The base salary range for this position is $170k - $240

Scale GP (Scale Generative AI Platform) is an enterprise-grade Generative AI platform providing APIs for knowledge retrieval, inference, evaluation, and more. We are seeking a strong Senior Full-Stack Engineer to help us build, scale, and refine our rapidly growing product. The ideal candidate is deeply grounded in software engineering best practices and experienced in developing and scaling modern web applications end-to-end. You will work across the stack—from React/TypeScript frontends to Python-based backends—while integrating with LLMs and machine learning systems. You will solve complex challenges in scalability, reliability, and product experience while owning significant product areas in a fast-paced environment. What You’ll Do Own major full-stack product areas , driving features from design through production deployment. Build modern frontend experiences using React and TypeScript, ensuring performance, usability, and responsiveness. Develop reliable backend services in Python, working with distributed systems, data pipelines, and ML/LLM components. Integrate with LLMs, vector databases, and AI infrastructure to power intelligent product experiences. Deliver experiments and new features quickly , maintaining high quality and tight feedback loops with customers. Collaborate across product, ML, and infrastructure teams to shape the direction of Scale GP. Adapt quickly —learning new technologies, frameworks, and tools as needed across the stack. Ideal Experience 5+ years of full-time engineering experience , post-graduation. Strong experience developing full-stack applications using React, TypeScript, and Python . Experience scaling or shipping products at high-growth startups . Familiarity with LLMs, vector databases, embeddings, or other modern AI tooling (tinkering or production experience welcome). Proficiency with SQL and modern API development. Experience with Kubernetes , containerization, and microservice architectures. Experience working with at leas

The Public Sector software engineers (SWEs) create the core product building blocks forward-deployed teams use to develop agentic capabilities that function across multiple domains. SWEs responsibilities include building the systems required to ingest and process federal datasets to support real-time decision-making in contested environments. We develop novel agentic enabling capabilities that includes: Create multi-layered guardrails around agents Optimize data retrieval for agents Orchestrate fleets of asynchronous agents Automatically alerts users to deviations in data Illustrating how an agent reached a decision As a Senior Software Engineer, you will lead the development of a vertical feature or a horizontal capability to include defining requirements with stakeholders and implementation until it is accepted by the stakeholders. You will: Lead the design and implementation of scalable backend systems and distributed architectures for Federal customers. Manage the full lifecycle of feature development from requirement definition to deployment on classified networks. Direct the orchestration of asynchronous agent fleets to meet mission requirements. Lead customer engagements to translate mission needs into technical requirements. Own the communication with stakeholders to ensure implementation meets defined acceptance criteria. Conduct technical reviews and identify risks within machine learning infrastructure and model serving. Drive the platform roadmap by providing technical specifications for Federal product offerings. Ideally you will have: Full Stack Development: Proficiency in front-end, back-end development and infrastructure, including experience with modern web development frameworks, programming languages, and databases Cloud-Native Technologies: Familiarity with cloud platforms (e.g., AWS, Azure, GCP) and experience in developing and deploying applications in a cloud-native environment. Understanding of containerization (e.g., Docker) and contai

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. The Luxury team builds rich and creative features that set the standard for the ride-sharing industry. We're looking for a motivated Senior Engineering Manager to lead the team building app experiences, UIs, and infrastructure for Black, Black SUV, and other upmarket modes where quality is uncompromising. As a Senior Engineering Manager, you'll set the technical direction for the team, making tradeoffs between technical investments and product work, and communicating strategy transparently to your team and to leadership. You'll act as a critical technical leader across backend, frontend, iOS, and Android, taking holistic ownership of complex systems, defining strategic roadmaps, and driving cross-functional alignment and engineering excellence to improve the luxury experience. Ownership is a key quality for this team. You should be driven to track projects to successful completion and beyond, taking initiative to work with other teams and functions to ensure your team's work reaches users and drives impact. You'll also help shape product direction by developing a deep understanding of the customer. You'll lead a group of talented engineers, helping the team deliver business impact while staying open to change through constant experimentation. You'll collaborate with engineering, product, data science, design, and operations on programs that empower the team to iterate quickly, delighting our passengers and drivers. If you enjoy collaborating with technical and nontechnical partners on a product with real-world impact, this is the role for you. Responsibilities: Lead a team of talented backend, frontend, and mobile engineers and engineering managers who like to ship code and tackle hard engineering problems Mentor and guide the professional and technical development of your team members. Help d

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. With a billion rides per year and counting, Lyft is solving hard problems in a rapidly growing domain with a lot of data and creative solutions in Rider, Marketplace, Growth, and beyond. While traditional approaches to optimization and problem decomposition are sufficient to disrupt transportation, building a next-generation platform for low-cost, ultra-immersive transportation to improve people's lives warrants modern ML utilizing peta-byte scale data. Our highly motivated Machine Learning Engineers work on these challenging problems and define solutions to directly impact various aspects of our core business. If you are a critical thinker with experience in machine learning workflows and LLMs, passionate about solving business problems using data and working in a dynamic, creative, and collaborative environment, we are searching for you. We are seeking a Senior Machine Learning Engineer to join the Rider Applied AI team and lead the design, development, and deployment of state-of-the-art machine learning and artificial intelligence systems. This role requires a strategic thinker who can balance high-level system architecture with hands-on technical implementation. You will collaborate across teams to shape the future of ride-sharing by leveraging AI, Machine learning and Data science. Responsibilities: Model Development & Research: Design, build, and deploy machine learning models for real-time applications, including translating state-of-the-art research into production-ready solutions. System Design: Architect scalable, reliable ML pipelines that integrate seamlessly with existing backend systems. Innovation & Applied Research: Stay ahead of the curve by exploring emerging algorithms, technologies (such as LLMs and LLM-based applications), and frameworks — critically eva

The Public Sector software engineers (SWEs) create the core product building blocks forward-deployed teams use to develop agentic capabilities that function across multiple domains. SWEs responsibilities include building the systems required to ingest and process federal datasets to support real-time decision-making in contested environments. We develop novel agentic enabling capabilities that includes: Create multi-layered guardrails around agents Optimize data retrieval for agents Orchestrate fleets of asynchronous agents Automatically alerts users to deviations in data Illustrating how an agent reached a decision As a Staff Software Engineer, you will orchestrate the implementation of vertical features and horizontal capabilities to include mentoring other engineers on defining requirements with stakeholders and communication tradeoffs of technical implementations on feature and capabilities until they are accepted by the stakeholders. You will: Orchestrate feature implementation across the Federal engineering team to ensure architectural consistency. Define technical strategy for agentic guardrails, explainability, and fleet orchestration. Ensure system reliability and performance across multiple security classifications and network types. Mentor engineers in the process of defining requirements with stakeholders and gathering acceptance. Communicate high-level technical trade-offs and implementation strategies to senior government stakeholders and Scale C-Suite members. Influence the long-term product strategy and technical roadmap for the Federal business unit. Consult on the architecture of AI-powered solutions for large-scale federal contracts. Ideally you will have: Full Stack Development: Proficiency in front-end, back-end development and infrastructure, including experience with modern web development frameworks, programming languages, and databases Cloud-Native Technologies: Familiarity with cloud platforms (e.g., AWS, Azure, GCP) and experience in

About Scale At Scale AI, our mission is to accelerate the development of AI applications. For 8 years, Scale has been the leading AI data foundry, helping fuel the most exciting advancements in AI, including: generative AI, defense applications, and autonomous vehicles. With our recent Series F round, we’re accelerating the abundance of frontier data to pave the road to Artificial General Intelligence (AGI), and building upon our prior model evaluation work with enterprise customers and governments, to deepen our capabilities and offerings for both public and private evaluations. About Data Engine Our Generative AI Data Engine powers the world’s most advanced LLMs and generative models through world-class RLHF (Reinforcement Learning with Human Feedback), human data generation, model evaluation, safety, and alignment. The data we are producing is some of the most important work for how humanity will interact with AI. Our Approach As part of the interview process, you’ll be considered for opportunities across several teams within the GenAI Engineering organization, based on your interests, expertise, and business needs. Potential team placements include Allocation, Growth, Frontier Data, Trust & Safety, Pay, Operator, or Tasking Experience. Together, these teams power Scale’s AI data operations - from building high-impact datasets that push the boundaries of LLM capabilities, to optimizing contributor onboarding and incentives, to safeguarding data integrity through advanced trust, safety, and security measures. They work at the intersection of ML, operations, and analytics to ensure we deliver the highest-quality data at scale. Responsibilities: Design, build, and maintain robust, scalable systems across the full stack, including front-end, back-end, and infrastructure layers Implement high-impact features using modern technologies such as TypeScript, React, Node.js, MongoDB, Elasticsearch, and Temporal Collaborate closely with internal operators (your use

Location: San Francisco, CA (Hybrid) What is Verse? The race to AI has become the race to power. Every breakthrough in artificial intelligence depends on one thing: access to electricity. But across the country, aging grid infrastructure and years-long interconnection queues are slowing the deployment of the data centers that will power the next generation of innovation. Solving this challenge isn't just about energy—it's about unlocking the future of AI. At Verse, we're building the energy intelligence platform for the AI economy. Our software helps the world's largest energy consumers achieve faster, cheaper, and cleaner power by combining real-time control of energy assets with complete visibility into their energy portfolio. Backed by Bessemer Venture Partners, GV, Coatue, and NVIDIA, and built by pioneers in grid-scale batteries, energy markets, and enterprise software, we're redefining how the world's most ambitious organizations access and manage energy. The Role We're seeking an experienced Senior Optimization Engineer to join our Data Science Team. In this role, you will lead the design, development, and deployment of optimization models that power our software platform across applications including electricity markets, renewable energy, and battery energy storage systems. You will be responsible for developing production-grade optimization engines that solve complex operational and planning problems at scale. This role requires deep expertise in mathematical optimization, strong software engineering skills in Python, and experience building optimization models that integrate with production systems. The ideal candidate has significant experience in the energy industry, particularly electricity markets and battery storage optimization. This position emphasizes technical leadership, ownership of complex optimization projects, and collaboration across engineering, product, and commercial teams to deliver high-impact optimization solutions. Key Res

Location: San Francisco, CA (Remote/Hybrid Available) What is Verse? The race to AI has become the race to power. Every breakthrough in artificial intelligence depends on one thing: access to electricity. But across the country, aging grid infrastructure and years-long interconnection queues are slowing the deployment of the data centers that will power the next generation of innovation. Solving this challenge isn't just about energy—it's about unlocking the future of AI. At Verse, we're building the energy intelligence platform for the AI economy. Our software helps the world's largest energy consumers achieve faster, cheaper, and cleaner power by combining real-time control of energy assets with complete visibility into their energy portfolio. Backed by Bessemer Venture Partners, GV, Coatue, and NVIDIA, and built by pioneers in grid-scale batteries, energy markets, and enterprise software, we're redefining how the world's most ambitious organizations access and manage energy. The Role As a Software Engineer focused on Fleet Telemetry & Control at Verse, you will be working closely with our energy solutions partners to design, implement, and test distributed energy resource controls and telemetry software on customer hardware at sites around the world. You will be part of a dynamic, high-performance team building applications directly on bare-metal or on hardware-level virtualization platforms. As an advanced technical leader in network programming and state management development, engineering teams will look to you for best standards and practices for interfacing with on-premises grid assets using solutions you will build and maintain. Key Responsibilities Foster a culture and mindset of well-designed systems, test-driven software, and transparent communication with a high caliber of mutual respect and consideration for stakeholders Mentor and support career and junior level engineers in their fleet telemetry and control software career development

Airbnb was born in 2007 when two hosts welcomed three guests to their San Francisco home, and has since grown to over 5 million hosts who have welcomed over 2 billion guest arrivals in almost every country across the globe. Every day, hosts offer unique stays and experiences that make it possible for guests to connect with communities in a more authentic way. The Community You Will Join: Providing world-class customer service for our community of guests and hosts is a critical mission at Airbnb. The Ambassador Routing & Channels (ARC) team sits within Airbnb Community Support and is responsible for powering intelligent, differentiated service experiences, ensuring every support request, across any channel, is addressed by the right expert at the right time. Our work directly drives faster resolutions, higher quality interactions, and exceptional customer satisfaction at scale. The Difference You Will Make: As a Senior Backend Engineer on the ARC team, you will contribute meaningfully across our core routing and differentiated service programs: Contribute to and lead engineering delivery on programs that enable intelligent agent matching, personalized support experiences for high-value customers, and next-generation routing and communication channel capabilities. Own and evolve core routing infrastructure, including decision engines, workflow orchestration, and routing rule management. Ensuring high availability, correctness, and scalability across millions of daily support interactions. Help drive consolidation of fragmented routing logic spread across multiple platforms and channels into a centralized, auditable, and maintainable system. Collaborate cross-functionally with Product, Operations, Data Science, and partner engineering teams to align on priorities and deliver outcomes that improve the customer support experience. Contribute to technical quality through design reviews, code reviews, and pragmatic architectural decision-making. Support the team's tech