Research Engineer / Machine Learning Engineer - B2B Applications

Join Lightning AI as a Senior Application Security Engineer specializing in the realms of Artificial Intelligence and Machine Learning. In this pivotal role, you'll be responsible for enhancing our application security posture across our innovative platforms. Collaborate with a team of talented engineers to identify vulnerabilities, implement security best practices, and ensure our AI-driven solutions remain robust and secure.

Saris AI develops applied AI solutions for the banking sector, with teams in San Francisco, Montreal, and Toronto. The company builds automation tools that handle complex, long-context reasoning and agent-driven decision-making. Reliability and compliance shape every product, and Saris AI's agents already manage real customer workflows in production. As revenue grows, the engineering team is expanding to enhance current offerings and explore new directions. The Senior Machine Learning Engineer role is based in San Francisco and sits within the core engineering group. The team works in a collaborative, early-stage setting, balancing infrastructure needs with the delivery of features that serve customers directly. What you will do Build and maintain machine learning infrastructure, such as evaluation frameworks, prompt management systems, and tools for model observability. Develop new AI features for customers while supporting and improving the underlying infrastructure. Shape strategies for evaluation, LLM routing, prompt engineering, and model selection. Set practical standards to boost quality without slowing down development. Guide technical direction by clarifying trade-offs and architectural choices. Requirements Minimum 4 years of experience in machine learning or AI engineering, including production deployment of ML systems. Direct experience with large language models, prompt engineering, evaluation techniques, and model routing. Background in building tools and systems that deliver value to users. Comfort making pragmatic trade-offs and recognizing when a solution is sufficient. Ability to navigate ambiguity, define problems, and deliver results independently. Strong focus on end users and understanding the impact of ML decisions on customer experience. Supports team growth through code reviews, collaboration, and clear technical communication. Bonus Experience in regulated industries, especially banking.

Join ema as a Senior AI Applications Engineer and play a pivotal role in developing cutting-edge AI solutions. You will collaborate with cross-functional teams to design, implement, and optimize AI applications that address real-world challenges. Bring your expertise in machine learning and software development to help us drive innovation and enhance user experiences.

Saris AI, based in San Francisco with teams in Montreal and Toronto, develops advanced agentic AI systems for the banking industry. The company focuses on automating complex workflows that require long-context reasoning, integration with legacy systems, and strict compliance. With live AI agents already supporting real customer operations, Saris AI is expanding quickly and seeking technical leaders who want to shape the future of work in banking. Role overview This is a hands-on leadership position within the core engineering team in San Francisco. The Machine Learning Engineering Lead will guide machine learning systems from initial concept through scaling, helping define both the technical vision and the supporting infrastructure. What you will do Oversee the ML/AI function end to end, setting technical direction and standards across the company. Design and supervise development of multi-modal, agentic AI systems that power live customer workflows. Build and manage evaluation frameworks, datasets, and metrics to improve agent performance. Drive productionization of ML systems with an emphasis on reliability, scalability, and compliance. Recruit, develop, and mentor a high-performing ML team, fostering strong practices in modeling, experimentation, and deployment. Requirements 8+ years of experience in machine learning or AI engineering, including time as a technical lead or manager. Proven track record leading ML projects from concept to production deployment. Expertise with large language models (LLMs) and/or agentic systems, especially in customer-facing products. Strong grasp of ML fundamentals: deep learning, transformers, model evaluation, and trade-offs. Hands-on experience scaling ML systems in production, with a focus on monitoring, iteration, and reliability. Ability to lead engineering teams, influence architecture, and set technical direction. Comfort working in early-stage, ambiguous, and rapidly changing environments.

Join Our Team as a Machine Learning EngineerSaris-AI is a pioneering applied AI startup, based in San Francisco and Montreal, focused on revolutionizing the banking sector. Our mission is to address a colossal $100 billion/year challenge that is rapidly expanding, innovating the limits of what can be achieved with advanced multi-turn AI systems.We aim to automate complex workflows that necessitate long-context reasoning, orchestration of tools across legacy systems, and rigorous compliance processes—solving problems that currently lack definitive solutions.Our team has successfully deployed AI agents that manage real customer workflows effectively in production. As we expand our customer base and accelerate our growth, we are in search of highly skilled technical builders who aspire to make a significant impact in the early stages of our journey.As a foundational Machine Learning Engineer, you will own our entire ML stack and bring custom agents to life.

About UsAt Citizen Health, we believe that the right advocate can significantly enhance healthcare experiences and outcomes. Founded on the principles of personal healthcare journeys, we leverage a unique combination of data, artificial intelligence, and community engagement to craft a personalized AI advocate. Our platform harnesses patients' comprehensive medical histories alongside data from a vast network of individuals, providing tailored insights for effective clinical decisions and everyday challenges. We focus initially on rare and complex conditions, allowing patients to share their information for mutual benefit, while empowering biopharma and researchers with regulatory-grade data that accelerates the drug development process for critical treatments.Our team consists of seasoned entrepreneurs with successful track records, backed by esteemed investors such as 8VC, Transformation Capital, and Headline Ventures. We are passionate about reshaping the future of consumer healthcare.Position OverviewCitizen Health is on the lookout for talented AI/Machine Learning Engineers to spearhead the development and implementation of innovative AI solutions for our patient-centered platform. This pivotal role involves crafting and deploying advanced machine learning models that convert intricate health data into actionable insights for patients, healthcare professionals, and researchers.As a vital technical leader, you will be at the cutting edge of applying sophisticated machine learning methodologies to tackle complex challenges in rare disease research and patient care. Your contributions will be crucial in developing AI-driven solutions that enhance disease comprehension, treatment options, and overall patient outcomes.Key ResponsibilitiesDesign and execute comprehensive machine learning solutions, covering data preprocessing to model deployment and ongoing monitoring.Develop and refine advanced Large Language Models (LLMs) tailored for healthcare applications, utilizing techniques such as fine-tuning and Retrieval-Augmented Generation (RAG).Construct robust data pipelines for validation and deployment processes.Implement machine learning systems capable of processing and analyzing diverse healthcare data types, including structured clinical data, medical imaging, and unstructured text.Collaborate closely with backend engineers to seamlessly integrate ML models into our production infrastructure.Ensure that ML systems adhere to rigorous healthcare compliance standards while maintaining optimal performance.

About VSCO At VSCO, we empower photographers with an innovative platform that provides essential tools, a vibrant community, and the visibility needed for creative and professional growth. We cultivate an authentic creative environment that welcomes photographers of all skill levels, offering a space that inspires opportunity, collaboration, and connection. Our mission is to support photographers in their journeys, enabling them to thrive and connect with fellow creatives and businesses through our comprehensive suite of tools, available on both mobile and desktop. We seek individuals who are passionate and proactive in advancing our mission. Our team members have the opportunity to make a significant impact, and we believe that collaborative efforts yield stronger results. Our core values are essential to our team culture and guide our hiring process. Learn more about what you can expect when joining VSCO on our Careers Page. About The Role As a Senior Machine Learning Engineer, you will harness the power of AI and machine learning to create innovative, reliable user-facing product features. You will leverage your extensive technical background and hands-on experience in deploying machine learning models to deliver impactful solutions based on real-world feedback. Your focus on measurable outcomes and customer satisfaction drives your work, blending innovation with practical implementation. You will be highly skilled in Python and adept across the data and machine learning stack, enabling you to develop and launch models efficiently while ensuring scalability and maintainability. Whether working with traditional algorithms or cutting-edge deep learning and generative AI, you will expertly navigate the complexity of each problem, managing every phase from defining the challenge to deployment and iterative improvement. Your dedication to software engineering excellence will inform your thoughtful approach to system design for machine learning, encompassing data quality, pipeline design, feature workflows, model serving, and ongoing monitoring and enhancement. By integrating machine learning deeply within our cohesive product experiences, you will collaborate effectively with cross-functional teams, aligning on objectives, defining success metrics, and driving meaningful outcomes. You will stay informed about the rapidly evolving AI landscape, maintaining a discerning perspective that allows your team to focus on significant advancements while avoiding distractions. The Day to Day Design and implement ML-powered features for search, discovery, personalization, and more.

Join Retell AI as a Senior Machine Learning EngineerRetell AI is at the forefront of revolutionizing the call center industry using groundbreaking voice AI technology. Within just 18 months of our inception, we have empowered thousands of businesses with our AI voice agents capable of managing sales, support, and logistics calls that traditionally required extensive human teams.Supported by renowned investors, including Y Combinator and Alt Capital, our journey has seen us scale from $5M to an impressive $36M ARR with a dedicated team of 20. Our ambition for 2026 is to develop a state-of-the-art customer experience platform, transforming entire contact centers with AI. We are building intelligent AI “workers” that will serve as frontline agents, quality assurance analysts, and managers—constantly executing, monitoring, and enhancing customer interactions.We are rapidly expanding and seeking passionate innovators eager to solve complex technical challenges and make a tangible impact in one of the fastest-growing voice AI startups. Together, let's shape the future of customer interactions.

Superhuman embraces a hybrid working model designed to offer team members the ideal balance of focused work and collaborative, in-person interactions that cultivate trust, innovation, and a vibrant team culture.About SuperhumanSuperhuman, now inclusive of Grammarly, is an AI productivity platform dedicated to unleashing the superhuman potential within everyone. Our suite of applications and agents extends AI capabilities across 1 million+ applications and websites. Our products include Grammarly's writing assistance, Coda's collaborative workspaces, Mail's inbox management, and Go, a proactive AI assistant that intuitively understands context and provides automated support. Since our inception in 2009, Superhuman has empowered over 40 million individuals, 50,000 organizations, and 3,000 educational institutions globally to reduce busywork and concentrate on what truly matters. Discover more at superhuman.com and explore our core values here.The OpportunitiesJoin us in developing a groundbreaking platform for AI Agents, designed to collaboratively tackle complex tasks, utilizing Superhuman's intuitive UI. As a Machine Learning Engineer on this pioneering team, you will play a critical role in our company's transformation.Shape the Future of Productivity: Take on a vital role in evolving Grammarly from a cherished writing assistant into an indispensable AI-driven productivity suite for enterprises.Build an Innovative AI Agent Platform: Lead the charge in creating a new platform where multiple AI agents work together to address intricate user challenges. You will oversee the core orchestration, routing, and planning systems.Own Key ML Systems: Design and implement advanced machine learning models that enhance core product experiences, including search ranking and proactive suggestions that anticipate user needs.

Highlight is pioneering a shared intelligence framework for the contemporary workforce. Our solution integrates context across every member and tool in your team, effectively eliminating information silos. As your organization evolves, Highlight adapts by intelligently routing knowledge and reliably automating workflows.The RoleWe are seeking a Senior Machine Learning Engineer to contribute to the development of the AI systems that drive Highlight's operations. This position involves working across the entire ML stack, including data pipelines, model training, retrieval, ranking, evaluations, and deployment. You will deliver features that create a seamless experience for our users. This is a hands-on individual contributor role where you will manage critical systems from inception to deployment, collaborating closely with our Head of AI Engineering to enhance our ML capabilities.You will excel in this role if you are passionate about delivering production-ready ML systems, maintaining high standards of output quality, and tackling complex problems that have a tangible impact on users. We prioritize speed, uphold rigorous standards, and believe in the merit of ideas, regardless of hierarchy.Note: This is an on-site position, requiring five days a week at our San Francisco or New York City offices.ResponsibilitiesDesign, develop, and refine ML pipelines for context retrieval, action detection, and output generation.Implement and iterate on Retrieval-Augmented Generation (RAG) systems, ranking models, and prompt engineering to enhance quality.Establish comprehensive evaluations and monitoring frameworks to assess and enhance ML system performance.Explore alternative models and fine-tuning strategies for our substantial background processing workloads, creating improved systems that enhance quality while optimizing cost efficiency.Work in collaboration with Backend and Product Engineering teams to deliver AI-powered features.Influence ML infrastructure decisions and establish best practices across the engineering organization.Stay updated on advancements in LLMs, retrieval techniques, and ML tools; share insights with the team.Candidate ProfileWe are looking for an individual who is excited about crafting the AI user experience for the future. We value extreme ownership, accountability, and proactivity as we strive to exceed expectations. The ideal candidate is a skilled craftsman who enjoys developing exceptional products utilizing LLMs at scale.You are a suitable candidate if you possess:4+ years of experience in ML/AI engineering, with substantial involvement in deploying production systems.

Artificial Intelligence (AI) is becoming increasingly crucial across all sectors of society. At Scale AI, our mission is to expedite the advancement of AI applications. With nine years of experience, we have established ourselves as the leading AI data foundry, facilitating groundbreaking developments in AI, including generative AI, defense applications, and autonomous vehicles. Following our recent investment from Meta, we are committed to enhancing our capabilities by developing cutting-edge post-training algorithms that are essential for optimizing complex agents in enterprises globally.The Enterprise ML Research Lab is at the forefront of this AI revolution. We are dedicated to crafting a suite of proprietary research tools and resources that cater to all of our enterprise clients. As a Machine Learning Research Engineer focusing on Agents, you will apply our Agent Reinforcement Learning (RL) training and building algorithms to real-world enterprise datasets across our clients and benchmarks. Your role will involve developing top-tier Agents that achieve state-of-the-art results through a blend of post-training and agent-building algorithms.If you are passionate about influencing the trajectory of the modern Generative AI movement, we would love to hear from you!

About Hike Medical Hike Medical is building the future of musculoskeletal care by combining advanced technology with practical healthcare solutions. Based in San Francisco’s Rincon Hill, the team develops a platform that spans three core areas: an AI-powered vision system for rapid web-based foot scans that generate custom 3D-printed orthotics, an AI agent platform that manages the entire DME workflow from intake through claims, and SoleForge, a high-scale 3D printing facility for custom medical devices. Hike Medical partners with some of the world’s largest employers and major orthotics and prosthetics organizations. Fortune 50 companies trust the platform to support employee well-being, and a broad network of clinical partners keeps the company connected to real-world needs. Custom insoles are just the starting point. The long-term goal is to reshape the industry with bionic devices: AI-designed, robotically manufactured orthotic and prosthetic products. The company aims to reach this milestone by 2040. Learn more at bionics2040.com. With $22 million raised across Seed and Series A rounds from leading investors, Hike Medical offers a results-oriented culture for those interested in the intersection of AI, manufacturing, and healthcare.

P-1380 Join Databricks as a Senior Applied AI Engineer, where you will harness the power of machine learning, scheduling, and optimization algorithms to enhance the efficiency and performance of our engineering systems and infrastructure. Our Applied AI team tackles some of the most challenging and fascinating issues in the industry, ensuring that Databricks infrastructure and products operate at peak performance and cost efficiency. This role is critical, as our customers depend on us to deliver the most optimized workloads. Your Impact: Develop comprehensive systems from the ground up within a dynamic team of seasoned professionals. Influence the direction of our applied machine learning investment areas by collaborating with engineering and product teams across the organization. Lead the design and implementation of advanced AI models and systems that enhance the capabilities and performance of Databricks' products, infrastructure, and services. Architect and deploy robust, scalable machine learning infrastructure, including data storage, processing, model training, serving components, and monitoring systems to facilitate seamless integration of AI/ML models into production environments. Explore innovative modeling techniques in the realm of machine learning for systems. Contribute to the wider AI community by publishing research, presenting at conferences, and actively engaging in open-source projects, thereby strengthening Databricks' reputation as an industry leader.

The Senior Machine Learning Engineer at Scale AI is tasked with harnessing advanced methodologies in generative AI, computer vision, reinforcement learning, and agentic AI to enhance our product offerings and streamline the customer experience in live environments. Our machine learning engineers utilize a robust internal infrastructure and unparalleled access to extensive datasets to drive significant improvements for our clients. As part of the Public Sector Machine Learning team, you will be at the forefront of deploying innovative models to critical government systems through groundbreaking products such as Donovan and Thunderforge. Our work encompasses various modalities, with a strong emphasis on large language models and computer vision. On the LLM front, we are developing sophisticated agentic systems designed to address intricate operational and planning challenges for government entities. This involves creating agent frameworks that interface with custom retrieval systems and production APIs, alongside evaluation tools for assessing and refining agent performance. Additionally, we are pioneering research in reinforcement learning for agentic LLMs, successfully deploying these innovations in real-world operational contexts. In the realm of computer vision, we are focused on training advanced models to boost labeling throughput and automate perception tasks. Our initiatives include developing large-scale fine-tuning pipelines, training models across diverse modalities, and creating adaptable vision foundation models to support a variety of defense applications.

Join Arcade as a Senior Machine Learning Engineer, where you'll be at the forefront of AI innovation. In this pivotal role, you will leverage advanced machine learning algorithms to create and enhance cutting-edge solutions. Collaborate closely with cross-functional teams to drive impactful projects from ideation to deployment.

Founding Machine Learning EngineerLocation: San Francisco, CA Work Model: In-office 5 days a weekAbout UsAt Effective AI, we are pioneering the future of work. Our vision is to push the boundaries of AI beyond mere repetitive tasks, focusing instead on intricate knowledge work that requires expertise and multi-faceted reasoning. We are developing advanced AI Teammates that are designed to navigate complex workflows and collaborate seamlessly with human professionals. Our initial focus is on the trillion-dollar U.S. Property & Casualty insurance sector, a domain rich with complexity and data, making it an ideal arena for our innovations.We proudly secured $10 million in seed funding from prominent investors including Lightspeed Ventures and Valor Equity Partners.Our committed team is based in San Francisco and thrives on in-person collaboration to tackle these significant challenges.Your RoleAs a Founding Machine Learning Engineer, you will be an integral member of our founding team, responsible for architecting, training, and deploying the agent loops that power our AI Teammates from inception. You will address some of the most pressing challenges in agentic AI and natural language processing, developing AI solutions adept at performing essential insurance functions such as underwriting and claims processing.Your responsibilities will include:Architecting and Developing Core ML Pipelines: Design, train, and fine-tune cutting-edge language models (including reinforcement learning agents) to facilitate long-term task accomplishment and complex decision-making.Implementing Nuanced Reasoning: Integrate machine learning techniques that empower agents to make informed decisions based on ambiguous or incomplete data, akin to human expert reasoning and generalization.Building Intelligent, Tool-Using Agents: Engineer the ML systems that enable our agents to dynamically select and utilize a broad array of external tools—including APIs, databases, web searches, and Excel-based pricing algorithms—to gather necessary information and execute actions.Designing and Implementing Robust Evaluation Frameworks: Create and employ comprehensive evaluation metrics and systems to rigorously assess and benchmark agent performance, identify areas for enhancement, and guarantee reliability and safety in real-world insurance processes.Enabling Continuous Adaptation and Learning: Develop resilient ML pipelines and feedback loops that facilitate ongoing learning and adaptation.

Why Join Brex?Brex is an innovative AI-driven spend management platform designed to empower businesses to manage expenses with confidence. We provide integrated corporate cards, banking solutions, and global payment options, alongside intuitive software for travel and expense management. From startups to large enterprises, clients like DoorDash, Flexport, and Compass leverage Brex to optimize spending, lower costs, and enhance efficiency worldwide.Joining Brex means embracing challenges, pushing boundaries, and collaborating with industry leaders. We are dedicated to fostering a diverse and inclusive culture where your potential is only limited by your aspirations. We equip you with the necessary tools, resources, and support to advance your career.Engineering at BrexOur engineering culture focuses on building scalable systems with intention and speed. Our teams, spanning Software, Data, Security, and IT, work with high autonomy and deep collaboration. We confront challenging technical problems, take ownership of outcomes, and strive for excellence across all levels—from architecture to deployment. Here, engineering is regarded as a craft, and builders evolve into leaders.Your RoleAs a Senior Application Security Engineer, you will be pivotal in identifying and addressing security vulnerabilities within the Brex platform. Your responsibilities will include conducting code and design reviews, penetration testing, and managing vulnerabilities. You will also develop and maintain tools for static and dynamic testing of the platform, ensuring secure developer workflows. You will collaborate closely with teams across Security Operations, GRC, Product Security, Front End Platform, and IT Infrastructure.We seek individuals with a robust background in penetration testing and a proven track record of uncovering vulnerabilities in complex systems. Your ability to craft exploits that highlight business risk will be essential. This role demands a collaborative spirit, as you will engage with various engineering teams throughout Brex. Your enthusiasm for diverse perspectives and needs is crucial as we build world-class financial services with top-tier security.Brex is at the forefront of AI-driven financial services for dynamic companies such as Coinbase, Robinhood, and Anthropic. As we integrate AI across our product suite, this role will have the chance to significantly influence our approach.

About Liquid AIFounded as a spin-off from MIT CSAIL, Liquid AI specializes in creating versatile AI systems designed for optimal performance across various deployment platforms, including data center accelerators and on-device hardware. Our technology emphasizes low latency, minimal memory consumption, privacy, and dependability. We collaborate with leading enterprises in sectors such as consumer electronics, automotive, life sciences, and financial services. As we experience rapid growth, we are on the lookout for exceptional talent to join our team.The OpportunityThe Data team at Liquid AI drives the development of our Liquid Foundation Models, focusing on pre-training, vision, audio, and emerging modalities. With the stagnation of public data sources, the effectiveness of our models increasingly relies on specially curated datasets. We are seeking engineers with a machine learning mindset who can efficiently gather, filter, and synthesize high-quality data at scale.At Liquid AI, we regard data as a research challenge rather than an infrastructural issue. Our engineers conduct experiments, design ablations, and assess how data-related decisions impact model quality. We will align you with a team where you can experience rapid growth and make a significant impact, be it in pre-training, post-training reinforcement learning, vision-language, audio, or multimodal applications.While we prefer candidates in San Francisco and Boston, we are open to considering other locations.What We're Looking ForWe are in search of a candidate who:Thinks like a researcher and executes like an engineer: You should be able to formulate hypotheses, conduct experiments, and evaluate results. Our engineers produce research-level code while our researchers implement production systems.Learns quickly and adapts: You will be working in rapidly evolving modalities, so the ability to quickly grasp new domains and thrive in ambiguity is essential.Prioritizes data quality: We hold data quality in high regard; tasks such as filtering, deduplication, augmentation, and evaluation are key responsibilities, not afterthoughts.Solves problems autonomously: Data engineers operate within training groups (pre-training and multimodal). While collaboration is crucial, we expect ownership and self-direction.The WorkDevelop and maintain data processing, filtering, and selection pipelines at scale.Establish pipelines for pretraining, midtraining, supervised fine-tuning, and preference optimization datasets.Design synthetic data generation systems utilizing large language models (LLMs), structured prompting, and domain-specific generative techniques.

Join Databricks Mosaic AI as a Senior Machine Learning Engineer and take the lead in developing our cutting-edge generative AI platform. Our team, formed in late 2020, empowers businesses by allowing them to securely fine-tune, train, and deploy custom AI models using their own data. This ensures maximum security and control while being compatible with all major cloud providers, allowing for unparalleled flexibility in AI development.Since our integration into Databricks in July 2023, we have been dedicated to tackling some of the world's most challenging problems, from revolutionizing transportation to accelerating medical advancements. We leverage deep data insights to enhance our customers' business capabilities and thrive on overcoming technical challenges to deliver superior data and AI solutions.Role Overview:As a Senior Machine Learning Engineer, you will play a pivotal role in the design and implementation of our generative AI platform, covering the entire ML development lifecycle, including data generation, training, evaluation, serving, and agent-building. Your expertise will be essential in translating user requirements into intuitive product interfaces while constructing robust backend distributed systems that drive these features.