Senior Backend Software Engineer

Join our dynamic team at Flex Ltd. as a Senior Backend Software Engineer! In this pivotal role, you will be responsible for designing and implementing robust backend solutions that power our innovative applications. You will collaborate with cross-functional teams to enhance system performance, scalability, and user experience.We're looking for a passionate …

Join the dynamic team at Kalshi as an International Expansion Specialist. In this role, you will play a pivotal part in driving our global growth strategy, identifying new markets, and spearheading the expansion initiatives that will position Kalshi as a leading player in the international landscape. You will collaborate with cross-functional teams to ensure seamless market entry and navigate the complexities of international regulations.

Join StubHub Inc. as a Senior Software Engineer in Active Support. In this role, you will be responsible for enhancing our platform's reliability and performance. You will collaborate with cross-functional teams to troubleshoot issues and implement innovative solutions to ensure the best user experience. Your expertise will drive significant improvements in our software and services.

Join Ramp as a Software Engineer and be instrumental in revolutionizing the travel experience. We are seeking innovative and passionate engineers to join our dynamic team, where you will have the opportunity to work on cutting-edge technology solutions that enhance travel efficiency and customer satisfaction.

Senior Software Engineer About IEX At IEX, we are dedicated to creating innovative technology that propels industries forward. Our journey started with the establishment of a stock exchange aimed at delivering exceptional results for all investors. We believe in democratizing technology, ensuring equitable opportunities for everyone. Drawing from our experience in developing a high-performance stock exchange, we are committed to crafting technology that simplifies complexities and accelerates growth in various sectors. Our ambition is to cultivate a trustworthy, disciplined, and diversified business, delivering transformative technology without compromising our core values. And this is just the beginning! What You'll Do: Collaborate with technology and operations teams to make informed design and architectural decisions for exchange solutions. Lead and contribute to the development and upkeep of C++ application frameworks, messaging APIs, data structures, application reliability, and recovery protocols. Manage and engage in the software development lifecycle, encompassing build, deployment, packaging, and dependency management stages. Assist in the development of systems such as order entry, market data, post-trade processing, and system monitoring and reporting. Work closely with Market Operations and Technology Operations teams to troubleshoot and resolve production issues effectively. Your Background: Proficient in C++ development within low latency environments. Familiarity with electronic trading systems, specifically the FIX Protocol, market data (both proprietary and SIP feeds), and post-trade processing. Experience with Linux operating systems. Preferred Qualifications: Experience with Java programming. Familiarity with KDB+ database systems. Knowledge of Python, Shell, or other scripting languages. Why You Should Apply: Comprehensive Benefits New hire stock equity (RSUs) 401K employer match Unlimited Paid Time Off (PTO) 100% coverage for medical, dental, and vision OneMedical membership 16 weeks of paid parental leave Flexible workplace options Employer charity matching program Learning and development stipend Commuter benefits Comprehensive onboarding program

Join Our Innovative Team at ConveoAt Conveo, we are revolutionizing the landscape of consumer and B2B research through our cutting-edge AI research platform. Our solution is trusted by leading global brands such as Unilever, Google, and Orange, providing them with valuable insights across marketing, product development, and research teams via our advanced AI video interviewer.Why Conveo?As we project significant growth—20x revenue by 2026—it's imperative to move beyond manual processes and spreadsheet solutions. We seek a talented GTM Engineer who thrives in a fast-paced environment to create, implement, and refine the internal tools and automation that empower our GTM team to excel.The current structure of our GTM team relies on a blend of SaaS tools, manual processes, and accumulated knowledge. Your role will be pivotal in transforming this setup into efficient, purpose-built applications, data pipelines, and AI-driven workflows. Imagine developing lead scoring models that continuously learn, creating effective attribution pipelines, and streamlining onboarding processes, all while significantly reducing manual tasks.This position is not your typical operations role; you will be hands-on coding, deploying applications, and utilizing tools such as Claude Code, Supabase, Node/TypeScript, and modern APIs. You will operate at the crossroads of engineering and GTM, measuring success through generated pipelines, automated FTEs, and enhanced customer activation.Reporting directly to the Chief Growth Officer (Florian), you will collaborate closely with the Sales, Marketing, Customer Success, and Product Engineering teams.Your Objectives1. Empower the GTM Team with Custom ToolsYour focus will be on creating bespoke solutions tailored to our team's needs rather than relying on generic tools.Develop and deliver in-house applications utilizing Supabase (Postgres, Edge Functions, Auth, Storage), Node/TypeScript, React, and Python.Design and implement customer-facing and internal dashboards and workflows to minimize manual tasks.Prototype swiftly: transition from concept to proof of concept in mere days.Oversee the entire development process: from data modeling and backend logic to frontend design and iterative improvements.2. Establish a Robust Data and Attribution FrameworkEnsure that every dollar of pipeline is traceable by building the necessary infrastructure.Create and uphold analytics and attribution pipelines, integrating GA4, GTM, and CRM systems.

Join Sandbar as a Senior Product Engineer for iOSAt Sandbar, we are pioneering an innovative human-agent interface that enhances individual autonomy in today's fast-paced world. Our talented team has developed state-of-the-art software, machine learning, and hardware solutions previously with industry leaders like Meta, Google, Apple, and more.Be part of the excitement as we prepare to launch our flagship product, Stream—a revolutionary private voice ring and conversational computer that has gained recognition from major publications like WSJ, Bloomberg, and Wired, set to ship in Summer '26.We invite you to contribute your expertise in creating an intuitive interface that empowers users to augment their capabilities.Your RoleWe are seeking a passionate Senior iOS Product Engineer to help shape the Stream app, which plays a crucial role in our user experience. You will collaborate with a cross-functional team consisting of design, firmware, and backend engineers to develop a seamless, technically robust application.Key ResponsibilitiesLead the iOS product development including architecture (Swift), performance optimization, testing, and deployment.Collaborate with backend services (WebSocket) and device integration (BLE) to ensure low-latency, reliable human-computer interactions.Work alongside product, design, and go-to-market teams to release updates, gather user insights, and iterate on improving user experiences.QualificationsA minimum of 5 years of experience in designing and deploying mobile applications for iOS.Expertise in Swift and complex interactive application development.Proven experience with OS-level integrations such as media control and on-device machine learning technologies.Familiarity with Python-based servers and the iOS Bluetooth stack is a plus.Exceptional communication skills across interdisciplinary teams.Strong sense of ownership and ability to navigate ambiguity while delivering high-quality technical outputs.A deep passion for enhancing user experiences and human-computer interaction.BenefitsComprehensive health, vision, and dental insurance.Unlimited paid time off and sick leave.Equity options in our early-stage company.

Join Sandbar as a Senior Hardware Lab Technician!At Sandbar, we are pioneering innovative interface solutions in the heart of New York City. Our mission is to empower individuals to navigate an agentic world, enabling free thought, action, and movement. Our talented team has developed cutting-edge software, machine learning, and hardware products for industry leaders such as Meta, CTRL-labs, Google, Apple, Fitbit, Peloton, and Equinox.Our flagship product, Stream, is an advanced human-agent interface—a discreet voice ring that serves as a conversational computer. Featured in prestigious publications like the WSJ, Bloomberg, and Wired, Stream is set to launch in Summer '26.As a Senior Hardware Lab Technician, you will play a crucial role in the development of wearable consumer electronics. Collaborating with our Electrical, Mechanical, Firmware, and Quality engineering teams, you will ensure seamless lab operations, prototype testing, and rapid iteration in our dynamic startup environment.

About FuboTV:FuboTV Inc. is a pioneering live TV streaming service focused on delivering a consumer-first experience that is reshaping the future of television.Recognized as one of Fast Company’s Most Innovative Companies (2026) and the Financial Times’ Fastest-Growing Companies in the Americas (2026, 2025), FuboTV also owns Hulu + Live TV (entertainment), Fubo (sports), and Molotov (entertainment and sports), streaming to audiences worldwide.Our Mission:We aim to provide premium sports, news, and entertainment content through an unparalleled user experience that prioritizes choice, flexibility, and value.About the Role:*This position is a hybrid role based in New York City. Candidates must reside in NYC and be willing to work in the office three days a week (Tuesday, Wednesday, Thursday).* We are on the lookout for a Software Engineer with a robust foundation in backend development and a solid understanding of infrastructure principles. This role is crucial for building and maintaining scalable, reliable, and high-performance systems that support our video infrastructure and core services. We need a hands-on engineer who thrives in both software delivery and system reliability.The Video Input/Output Systems team oversees all facets of linear video operations, including ingestion, storage, distribution, advertising, scheduling, and client playback at scale.This is a fantastic opportunity for a software engineer to engage with both internal and external stakeholders, crafting efficient systems that align with critical business objectives. You will collaborate closely with our Streaming Media Operations (Acquisition, Encoding, Operations), Advertising Engineering, Platform, Product Management, Players, Content Distribution, and Sales teams to create integrated solutions.What You’ll Do:Design and implement high-throughput, low-latency video backend services, focusing on scalable architecture, efficient data processing, and fault-tolerant behaviors during peak traffic.Integrate services with comprehensive metrics, distributed tracing, structured logging, and health checks to enhance real-time observability and actionable alerts.Manage the reliability lifecycle—from establishing SLIs/SLOs to leading incident responses, triage, on-call rotations, and long-term reliability engineering initiatives.Architect scalable and event-driven services and microservices to support millions of concurrent viewers.Collaborate extensively with SRE and partner teams to fine-tune service performance across edge caches.

About SomethingsAt Somethings, we are pioneering a revolutionary social wellness platform specifically designed for teens. Our mission is to create a supportive environment where young individuals can build meaningful relationships with mentors who truly understand them, are dedicated to their growth, and provide the guidance necessary for them to flourish.In the U.S., 25 million teens face mental health challenges, and each of the countless teens who engage with Somethings requires assistance. Our goal is to ensure that these individuals do not merely use the platform, but instead connect with compassionate humans who are devoted to their well-being and help them thrive.With backing from General Catalyst and esteemed healthcare and consumer investors, we are experiencing rapid growth — achieving a remarkable 1100% increase in 2025 and aiming for a fivefold growth in 2026.If you aspire to contribute to a transformative company within the mental health sector, we welcome you to join us.Role OverviewWe are seeking a Senior Fullstack Software Engineer specializing in React to join our dynamic, high-impact engineering team. You will play a pivotal role in constructing the foundational web experiences that empower our mentors and operational teams.This position offers high levels of agency, craftsmanship, and impact:You will directly influence the platform experiences that assist teens in connecting and genuinely improving their lives.What You'll DoIn this role, you will take complete ownership of essential projects that align with our strategic objectives for 2026:1. Transform our Mentor Operations Platform into a world-class experienceDeliver web experiences that are fast, reliable, and deeply human-centric.Evolve the mentor web experience from basic functionality to a cohesive, elegant, and leading-edge platform.Create user interfaces that are as intuitive and refined as the best consumer applications.Prioritize performance, accessibility, and interaction quality.2. Develop tools that safely scale our mentor operationsDesign features for mentors that enhance consistency, speed, and connection.Implement safety measures that proactively identify risks and minimize human error.Refine mentor workflows to empower users rather than overwhelm them.3. Take charge of full-stack product developmentBuild comprehensive features across React, backend services, and APIs.Engage in close collaboration with design, product, growth, and clinical operations teams.

Current is a pioneering consumer fintech platform that is redefining financial accessibility for everyday Americans, boasting over 6 million members. Our platform integrates financial solutions that work in harmony to meet the diverse needs of our users, empowering all Americans to forge better financial futures. Based in the heart of NYC, our dynamic, results-focused environment motivates us to develop superior products, accelerate growth, and enable every team member to make a meaningful contribution toward our mission of enhancing financial well-being. The Engineering team at Current is committed to constructing our products and infrastructure. Our applications are powered by Google Cloud Kubernetes Engine, supporting a proprietary banking core capable of processing millions of transactions daily. Our technology stack features MongoDB and Spanner for data persistence, Pub/Sub for asynchronous event handling, Dataflow for data transformation, and BigQuery alongside Google Cloud Storage for data analytics and storage. Our backend services utilize Java, and our data pipelines are crafted in Scala. We operate across a wide array of domains, including user-centric products such as liquidity offerings and reward programs, infrastructure to support machine learning and experimentation, real-time fraud detection, identity protection, and large-scale transaction processing across various payment channels. We are on the lookout for a Senior Backend Engineer to join our New York team. This role offers a competitive salary range of $170,000 - $250,000. As a pivotal member of our team, you will spearhead key business initiatives, enhance existing architecture and services, and design large-scale, data-intensive applications. The ideal candidate will possess a solid background in backend development with experience in cloud-hosted services. A self-motivated individual who thrives in a fast-paced environment will excel in this role.

About ArkadiumJoin Arkadium, where our mission is to infuse enjoyment into everything we create. With 25 years of experience, we have developed some of the most popular games worldwide, from the iconic Solitaire included with Windows to an expansive array of web and mobile games that captivate millions.As a proud Evergreen company, we embody values of Fierce Drive, Positive Energy, and Living Full Lives, which shape our product development, team leadership, and sustainable growth. Being founder-led and privately held, we consistently earn accolades as a Best Place to Work, distinguishing us from conventional games companies.Are you ready to become an Arkadian? We would love to connect with you! The OpportunityAs the General Manager, you will take full ownership of Arkadium's consumer games business, overseeing every aspect from end to end. With complete P&L accountability, you will report directly to the CEO and craft strategies for portfolio development, platform expansion, and both organic and inorganic growth.This hands-on leadership position involves collaborating with a talented team, setting high standards for excellence in game development, distribution, monetization, and execution.What You'll OwnP&L & Commercial Strategy: Take charge of consumer games revenue streams, including ads, subscriptions, microtransactions, and distribution partnerships.Portfolio & Game Development: Determine the direction of game development, licensing, and retirement across various titles.Platform & Product: Lead the product roadmap for arkadium.com, enhancing engagement features, retention mechanics, monetization strategies, and user experience.New Platforms: Spearhead our expansion into emerging distribution channels such as mobile apps and Instant Games.Inorganic Growth: Shape our M&A strategy through studio partnerships, IP agreements, and catalog acquisitions.Team Development: Guide director-level talent across Games, Platform, Creative, and Analytics departments.RequirementsWhat We’re Looking ForExtensive experience as a VP, GM, or Head of Studio with direct P&L responsibility in the consumer games sector.A proven record of launching successful games that retain players and drive revenue, preferably in casual or mid-core genres.Experience managing or overseeing a consumer-facing web platform or gaming website.In-depth knowledge of ad-monetized models and user-centric product decisions.Leadership experience with multidisciplinary teams across design, product, creative, and analytics.A strong belief in what makes games engaging and enjoyable.PreferredExperience in web casual gaming, particularly targeting audiences aged 35 and above.Experience expanding platforms (mobile, social media, new distribution channels).Proficiency in building experiences for players who value innovative engagement.

About AmigoAt Amigo, we collaborate with healthcare organizations to implement cutting-edge AI infrastructure that directly benefits both patients and providers. Our intelligent agents manage clinical workflows and enhance patient engagement throughout their entire experience: from pre-visit intake and care navigation to post-visit care plans and ongoing patient monitoring.Having recently completed our Series A funding led by top-tier investors such as Madrona, General Catalyst, and Optum Ventures, we are proud to have our work validated by leading academic medical institutions. Our agents have successfully facilitated over 3 million patient encounters and are projected to increase this number tenfold this year.About This RoleAs a Senior Full-Stack Engineer at Amigo, you will be responsible for shaping the technical strategy of our foundational applications that drive clinical operations. You will lead the development of three key products: Control Center, which provides real-time oversight of agent interactions; Research Platform, enabling natural language queries over healthcare data; and Agent Forge, a no-code tool for designing agent behaviors.In this role, you will make critical architectural decisions, establish engineering standards, and develop scalable systems that handle sensitive patient information. Reliability and accuracy are essential, as these applications support vital clinical workflows. You will also mentor fellow engineers, cultivate a strong technical culture, and ensure that our elite engineering standards are upheld as the team expands.Key ResponsibilitiesLead the technical architecture and system design for Control Center, Research Platform, and Agent Forge.Establish engineering standards for code quality, testing, observability, and incident response.Develop real-time systems for clinical oversight, including streaming conversations, escalation workflows, and audit trails.Design the technical framework for natural language queries over healthcare data.Create no-code tools that empower non-engineers to design and configure agent behaviors.Design APIs, data models, and caching strategies that facilitate real-time streaming, voice, and multi-channel communication.Oversee authentication, authorization, and audit logging architecture to ensure compliance with healthcare regulations.Make informed decisions on build vs. buy strategies and assess technical trade-offs across the platform.Mentor engineers and implement practices that uplift the skills and standards of the entire team.Collaborate with agent engineers, clinicians, and clients to grasp complex workflow needs.

Based in the vibrant heart of New York City, RXR Realty LLC is a premier vertically integrated investment management firm with a diverse team of over 450 professionals. Our expertise spans a wide range of value-added activities, including acquisitions, asset and portfolio management, property operations, development, construction, leasing, and cutting-edge technological advancements. RXR is proud to be an active investor in real estate credit, rental housing, commercial properties, and property technology, employing strategic investment strategies aimed at maximizing value.Role Overview We are seeking a dedicated Project Executive to join our team in partnership with TF Cornerstone. This role will support the owner’s team in delivering the ambitious 175 Park Avenue project—a ~3 million square foot mixed-use tower integrated with transit, located adjacent to the iconic Grand Central Terminal. This project encompasses office space, ultra-luxury hotel accommodations, premium amenities, and significant improvements to the transit network. In this pivotal role, you will oversee the daily coordination with the design team and provide strategic guidance to the Construction Manager. Your responsibilities will include managing the scope, schedule, budget, risk, and reporting throughout the various phases of the project.

Role Overview The City of New York is hiring an entry-level Computer Associate (Software) to help build and maintain software applications for city operations. This role supports essential services and contributes to technology that serves New Yorkers every day. What You Will Do Develop and maintain software tools used across city departments Work alongside a team focused on improving city services through technology Support ongoing projects that impact daily life in New York City Location Position based in New York City.

Role overview Betterment seeks a Senior Software Engineer to join the team at its New York City headquarters. Senior engineers at Betterment play a key role in building software that helps people manage their finances more effectively. This position involves close collaboration with peers to shape the future of personal finance technology. What you will do Work with fellow engineers to design and launch new features for the Betterment platform Create solutions that enhance the user experience Help build scalable systems to support the company’s growth Write code that is both high-quality and maintainable Requirements Background in building software products, preferably within finance or technology sectors Ability to work well in a collaborative environment, including periods of rapid development Interest in technology and financial services

Role overview Iterative Health seeks a Staff Software Engineer to help create software that improves healthcare delivery and patient outcomes. This role focuses on projects with significant impact and involves close collaboration with teams throughout the company. What you will do Design and build software solutions tailored to healthcare applications Collaborate with colleagues from different disciplines to deliver effective products Use advanced technologies to address practical healthcare challenges Locations Cambridge, Massachusetts, United States New York, New York, United States

Role overview Playground is hiring a Vice President of Small and Medium Business (SMB) Sales to lead its sales strategy and execution for the SMB market. This executive position is based in New York City and will influence how Playground connects with and supports small and medium businesses. What you will do Lead, mentor, and grow a diverse sales team, fostering strong performance and collaboration. Develop and implement initiatives to attract new SMB customers and strengthen Playground’s reach in this market. Partner with teams across the company to refine product offerings and create a seamless customer experience. Use data and market insights to identify growth opportunities and guide strategic decisions. Requirements Significant experience as a sales executive, with a proven record of building and scaling teams in the SMB space. Ability to set sales strategy and consistently achieve targets in a competitive environment. Leadership style that motivates teams and encourages creative problem-solving. Location This role is based in New York City.

Decagon seeks a Senior Research Engineer based in New York City. This role centers on driving research initiatives and developing new technologies that align with the company’s objectives. Role overview The Senior Research Engineer collaborates with team members from various disciplines. The work involves designing experiments, analyzing outcomes, and creating solutions for complex challenges. Key responsibilities Advance research projects that contribute to Decagon’s goals Build and refine technologies to address technical problems Work with colleagues from diverse backgrounds to design experiments and interpret findings

The City of New York seeks a Neighborhood Contract Manager to join its Brooklyn office. This role centers on managing contracts that help build stronger community infrastructure and improve services in urban neighborhoods. Key Responsibilities Manage contracts that contribute to neighborhood development and public services. Work closely with city agencies, vendors, and local partners to achieve contract objectives. Track contract compliance and resolve any issues that come up during the process. Who Will Succeed Candidates with a genuine interest in urban communities, contract oversight, and public service will find this position rewarding. Experience collaborating with a range of stakeholders is helpful.