Machine Learning Engineer

Senior Machine Learning Engineer I

Sumup

About the team: Within the Global Operations organisation, our mission is to build the best customer experience in the fintech industry by delivering an effortless customer experience to all our merchants. We are seeking a skilled and passionate Senior AI / Machine Learning Engineer to join our talented AI team and lead the development of AI models and algorithms that will drive our customer support service to new heights. As a Senior AI / Machine Learning Engineer at SumUp, you will be responsible for building and optimizing state-of-the-art AI models and algorithms. Your expertise with machine learning, deep learning, and LLMs will be crucial in driving the success of our AI-driven initiatives. You will work closely with cross-functional teams, including backend engineers, data scientists and product managers, to translate business requirements into innovative AI solutions. Your contributions will shape the future of our support products and help us stay at the forefront of technological advancements in the field of AI. What you’ll do * Architect, design, develop and deploy our AI solutions and systems in production environments, ensuring reliability, high performance and scalability. * Collaborate and communicate closely with data scientists, product managers, developers and other business stakeholders to bring state-of-the-art AI solutions to Customer Support, enhancing customer experience and improving operational efficiency. * Develop and maintain ML infrastructure and pipelines to support efficient data processing, model training and serving. * Optimize and fine-tune machine learning models to improve accuracy, efficiency and scalability. * Collect, preprocess and clean large text datasets to ensure high-quality input for model training and evaluation. * Embrace software development principles, best practices and industry standards, including version control, CI/CD processes and unit testing frameworks as your day-to-day work. * Collaborate with cross-functional teams to ensure seamless integration of machine learning solutions into software applications and platforms.  You’ll be great for this position if you have: * Bachelor’s degree in Machine Learning, Computer Science or an engineering-related field. * +8 years of proven experience working as a Machine Learning Engineer, focusing on building and deploying scalable machine learning or AI solutions and data-driven systems. * Relevant experience building AI products, such as Chatbot Assistant, RAG system, etc. * Excellent software development engineering skills to design computationally effective solutions and maintenance in large-scale production environments (data version control, model serving, continuous monitoring & alerting) * Experience building and deploying ML models using cloud services (AWS, GCP, or Azure). * Expert in Python and familiarity with MLOps tools (e.g., MLflow, Kubeflow, Airflow, Langfuse). * Experience with machine learning workflow orchestration and algorithms optimisation, feature engineering pipelines, data ingestion and transformation.  * Good understanding of data pipelines, APIs, containers (Docker), and version control (Git). * Excellent analytical and problem-solving skills, with strong attention to detail. * You have working proficiency and communication skills in verbal and written English. Why you should join SumUp: 🌍 Opportunity to work with SumUppers globally on large-scale fintech products used by millions of businesses worldwide, from our Berlin office. This involves an office-first setup. 🌈 Commitment to Diversity and Inclusion: Be part of a workplace that values and promotes diversity, fostering an inclusive environment where everyone's perspectives are respected and embraced 📚 A dedicated annual L&D budget of €2,000 for attending conferences and/or advancing your career through further education. 🚀 Enrolment onto our VSOP program: You will own a stake in SumUp’s future success 💶 A corporate pension scheme where we match up to 20% of your contributions 🔄 30 Days Sabbatical: Enjoy the unique opportunity to take a well-deserved break with our 30 days sabbatical benefit after completing 3 years of employment with SumUp. 🔗 Referral Bonus: Earn additional rewards by referring talented individuals to join the SumUp team. 🚵🏾‍♂️ Numerous other benefits such as Urban Sports Club subsidy, Kita placement assistance, relocation assistance, subsidised office lunches. About us: SumUp is a leading financial technology company, founded in 2012 with the goal of empowering small businesses around the globe. We’re the financial partner of choice for more than 4 million merchants in over 35 markets. We collectively build, plan and fine-tune the technology that drives SumUp and empowers small businesses around the world. We believe in the everyday hero. Those who have the courage to follow their passion and who have the strength and determination to realise their dreams. Small business owners are at the heart of all we do, so we're creating powerful, easy-to-use financial solutions to help them run their business. With a founders mentality and a 'team-first attitude' our diverse teams across Europe, South America, and the United States work together to ensure that small business owners can be successful doing what they love. SumUp is an Equal Employment Opportunity employer that proudly pursues and hires a diverse workforce. SumUp does not make hiring or employment decisions on the basis of race, colour, religion or religious belief, ethnic or national origin, nationality, sex, gender, gender identity, sexual orientation, disability, age or any other basis protected by applicable laws or prohibited by Company policy. SumUp also strives for a healthy and safe workplace and strictly prohibits harassment of any kind. Job Application Tip We recognise that candidates feel they need to meet 100% of the job criteria in order to apply for a job. Please note that this is only a guide. If you don’t tick every box, it’s ok too because it means you have room to learn and develop your career at SumUp.

Senior Machine Learning Engineer, AI Platform

Smartly

We are looking for a Senior Machine Learning Engineer to join the AI Platform Team at Smartly! Our team works on helping marketers make the most of their ad creatives (images, video, text) and campaigns (product and performance data). We build and experiment with AI-based solutions across the media and creative workflows.You will have the opportunity to take ownership of and work on high impact projects. Join us in building high impact ML-based solutions to help our customers to build better and more effective advertising experiences for their consumers. If you’re a growth minded individual who has a passion for ML and the marketing space, this team is for you! AS A SENIOR MACHINE LEARNING ENGINEER, YOU’LL: * Build ML-based software systems that enable our users to craft great advertising experiences and campaigns  * Work with a large span of datasets from image to video to audio to text to structured performance data. * Contribute to and strengthen Smartly’s MLOps + data platform. You’ll work alongside our stellar senior machine learning engineers, data scientists, and software engineers to enable us to productionize AI/ML applications more robustly and efficiently. * Be a core contributor of our team and our ways of working to build high impact products. You’ll actively be involved in work planning, retrospectives, and overall team improvement. * Impact the daily life of the staff of the hundreds of advertisers using Smartly  * Work with our stakeholders - be them product, engineering, infrastructure - to ensure we meet customers where they are. As with most ML-related roles, being able to translate business/product needs to viable solutions is a must. * Apply and enhance your soft skills through working closely with your colleagues and our customers. Doing knowledge shares, running productive meetings, and pair programming/debugging are just some ways we grow our soft skills. * Keep up to date with the latest ML innovations, especially in areas such as generative AI, computer vision, natural language processing and explainability. WHAT WE ARE LOOKING FOR: * 5+ years of experience developing and deploying production-quality software * 2+ years of experience delivering software services powered by machine learning * 2+ years of experience working with cloud infrastructure such as AWS or GCP * Fluent in Python; experience with C++ or Java is a plus * Hands-on experience with modern ML frameworks (e.g., PyTorch, TensorFlow) * Knowledge of MLOps concepts and tools (e.g., MLflow, Kubeflow) * Experience in feature engineering, model evaluation, diagnostics, and monitoring * Strong foundation in linear algebra, statistics, and calculus * Experience building scalable data pipelines for ML-based data processing * Experience developing and maintaining services under SLA * Analytical mindset with a problem-solving approach * Passion for solving customer challenges quickly while making thoughtful architectural decisions * Adaptability and resilience when facing new or ambiguous challenges * Strong written and verbal communication skills in English * M.Sc. in a relevant field is preferred * Ability and willingness to work in a hybrid capacity from our office 3 days a week WHAT WE OFFER YOU At Smartly, we offer a place where you can advance your career. Here, you'll find: An Inclusive Global Culture: Join a team of over 750 Smartlies, representing more than 60 nationalities across 24 locations in 13 countries. We cultivate a culture built on trust, transparency, and open feedback, where diverse perspectives are valued and encouraged.  Global Impact: Contribute to a company making a global impact, directly influencing our customers' success and business growth. Focus on Wellbeing: We prioritize your health with healthcare packages, mental health services, and a commitment to work-life balance through paid holidays and family leave. Comprehensive Rewards: Benefit from equity options, performance-based rewards, competitive compensation, and career development opportunities. Flexible Hybrid Workplace: Experience a hybrid work model, balancing office collaboration with remote work, and the option to work abroad for up to 30 days annually.   Apply Now and Build Your Future with Smartly! Curious what it’s like to work at Smartly? Visit our Careers page to see how we grow, collaborate, and make impact together ABOUT SMARTLY Smartly is the AI-powered advertising technology company transforming ad experiences for brands and their consumers. Our comprehensive advertising platform seamlessly integrates the capabilities of media, creative, and intelligence to power more than 800 billion impressions and generate more than 300 billion creatives annually, delivering tangible business outcomes for brands and advertisers. Smartly is the only company in the industry recognized as a Leader in The Forrester Wave: Creative Advertising Technologies with PwC validating the results it delivers for brands. We manage creative and media for 700+ brands worldwide and $6B in ad spend across the largest media platforms, including Facebook, Google, Instagram, Pinterest, Snap, and TikTok. Our end-to-end technology, unmatched access to media platforms and exceptional customer service help Fortune 500 brands to reach and engage consumers and learn what performs best.Smartly is a multinational and diverse team of 750+ Smartlies from 60+ nationalities, working in 13 countries. Together, we want to create and maintain an inclusive environment where everyone feels respected and heard. Our Diversity, Equity & Inclusion approach is at the heart of it. Visit Smartly to learn more. The processing of your information is described in our Candidate Privacy Notice.

Senior/Staff Machine Learning Engineer

Vestiaire Collective

Vestiaire Collective is the leading global online marketplace for desirable pre-loved fashion. Our mission is to transform the fashion industry for a more sustainable future by empowering our community to promote the circular fashion movement. Vestiaire was founded in 2009 and is headquartered in Paris with offices in London, Berlin, New York, Singapore, Ho Chi Minh, and warehouses in Tourcoing (France), Crawley (UK), Hong Kong and New York. We currently have a diverse global team of 600 employees representing more than 50 nationalities. Our values are Activism, Transparency, Dedication and Greatness and Collective. About the Role We are seeking a Foundational Machine Learning Engineer for a high-impact greenfield opportunity to build our MLOps infrastructure from the ground up at Vestiaire Collective. While driving our AI authentication initiatives (deploying multi-model approaches including computer vision for luxury product authentication and counterfeit detection) will be your immediate focus, your long-term mission will be to scale foundational architecture across the entire marketplace. You will expand our ML capabilities to power broader domains, primarily focusing on search and recommendation systems, with future expansions into dynamic pricing and marketing technologies. Acting as the bridge among Applied Science, Data Platform, and Backend Engineering, you will design robust, decoupled architectures and spearhead the MLOps strategy with our Director of Data, prioritizing system maintainability, engineering hygiene, and the reliable deployment of complex models, ensuring all our ML models across the board deliver high-throughput, low-latency business impact. What You Will Do Short-Term Impact (First 6 Months): Partner closely with the Operations squads and Data Scientists to accelerate ML and RAG prototypes into resilient, production-ready code. You will directly integrate with the team to deploy, optimize, and scale heavy-width CV and VLM models focused on fraud detection and luxury product authentication, immediately improving our trust and safety ecosystem. Mid-Term Foundation (MLOps Lifecycle & Infrastructure): Lead the end-to-end foundational groundwork of our ML lifecycle by designing robust systems for Data & Feature Management, Model Tracking & Registry, and Model Serving & Monitoring. You will scale infrastructure by automating continuous retraining pipelines that handle diverse deployment cadences (from daily fraud detection to weekly recommendations), design resilient multi-model architectures, and critically evaluate the technical overhead and TCO of our in-house tools against enterprise-grade platforms to ensure long-term resilience. Long-Term Vision (Centralizing 360-Degree MLE Capabilities): Act as a pioneer and cornerstone hire for the ML engineering discipline at Vestiaire Collective, setting the technical standards to help scale the AI/ML organization. You will transition into a centralized foundational role, moving beyond single-squad operations to mentor the team and provide horizontal ML infrastructure support to multiple domains, including Search, Discovery, Pricing, Marketing, and Data Platforms. Who You Are Must-Haves: Experience: 5-8+ years of hands-on experience in Machine Learning Engineering, specifically focused on building and scaling MLOps infrastructure and productionizing ML systems. Production Infrastructure: Proven expertise in deploying low-latency, high-throughput ML inference services (using FastAPI, TorchServe, Triton Inference Server, or Ray Serve) across both classical lightweight and heavy-width ML models (PyTorch/TensorFlow). Strong preference for AWS (EKS, EC2, SageMaker) / Snowflake and Open Source ecosystems over GCP/Azure. MLOps & Pipelines: Deep experience building automated, continuous model retraining pipelines to handle concept drift (ranging from daily to weekly cycles). You have orchestrated decoupled, multi-model AI architectures using tools like Airflow, Kubeflow, or Metaflow, and possess strong expertise in model registry and tracking tools like MLflow or Weights & Biases. Feature Stores: Hands-on experience evaluating, building, or extensively leveraging online (Redis, DynamoDB) and offline (Snowflake, S3) Feature Stores in a production environment. Familiarity with frameworks like Feast or custom dbt-based pipelines is highly valued. Strategic Builder Mindset: You are an analytical builder who thinks long-term. You can successfully evaluate TCO for bespoke internal systems versus enterprise tools, anticipate technical liabilities, and design robust architectures that handle unpredictable peak traffic surges. Collaboration & Engineering Hygiene: Strong cross-functional communication skills. You excel at translating complex ML prototypes into highly scalable production code backed by strict version control, rigorous testing, and CI/CD best practices, seamlessly connecting data science innovation with backend engineering execution. Nice-to-Haves: Relevant Domain Expertise: Background in E-commerce, Single-SKU Marketplaces, Search & Recommendation, Trust & Safety, or Counterfeit Detection. Vision, Edge & Optimization: Hands-on experience with Vector Databases, Visual RAG pipelines, deploying Deep Learning VLM models, and optimizing models for edge computing or low-latency inference (e.g., ONNX, TensorRT). Infrastructure & Observability: Advanced experience with containerization (Docker, Kubernetes), Infrastructure as Code (Terraform), and data transformation workflows (dbt). Familiarity with setting up advanced monitoring for model performance, concept drift, and system health (Datadog, Prometheus).