
Chattermill · UK
Data Scientist 🌍 UK (Remote or Hybrid, it’s up to you!) 💰 Dependent on experience 📈 Be part of our success with the opportunity to join our company equity...
Data Scientist
🌍 UK (Remote or Hybrid, it’s up to you!)
💰 Dependent on experience
📈 Be part of our success with the opportunity to join our company equity scheme
🦸♀️ The Role 🦸♀️
Our mission is to help large successful brands like Uber, Amazon, Wise, HelloFresh (and more!) put their customers at the centre
of everything they do. Using best-in-class tech in a fast-developing AI space, our Customer Experience Intelligence platform
continuously analyses explicit and implicit feedback to enable our clients to identify what they should do next.
We're hiring a Data Scientist to join the team and help build and ship the next generation of that stack.
Unlike many companies, we use our own custom models, specialised for customer feedback, across various parts of the stack:
extraction, retrieval, reranking, summarisation, and sentiment analysis. We are also pragmatic and understand that the right
solution can be a combination of off-the-shelf LLMs, bespoke fine-tuned models, and sometimes techniques that utilise no LLM at
running experiments with rigour and clear documentation.
and guidance from senior team members.
extraction, and generative tasks.
that go beyond them.
solutions.
techniques such as LoRA is a plus.
meaningful scale.
🔎 Our Hiring Process
1. Let’s introduce ourselves – you’ll complete an introductory asynchronous interview - we’d love to learn more about you, your
ambitions, and what you’re looking for in your next step.
2. Get to know your would-be manager – you’ll have a call with Aji, our Chief Scientist, to learn more about the role and show
off your experience.
3. Show us how you work – you'll complete a short take home assignment
4. Get to know your would-be team – You'll meet a mix of people who you'll be working closely with from the Data Science,
Engineering and Product teams.
5. How our values and your career goals align – you’ll have a call with our cofounder to learn more about life at Chattermill and
ensure we’re the right place for your next stage of growth.
Our Perks
🤸🏽♂️ Flexibility & Work Setup
🌴 Time Off
🌱 Growth & Ownership
💚 Health & Wellbeing
🌆 Office Perks
💖 Our Values
what we preach.
communicate with openness and trust.
decisions in our area of responsibility is a crucial driver for us.
of reach. We recognise that we are learning machines and we always seek to action feedback and improve collectively.
before. While we're an ambitious bunch with lofty goals, we don't approach this goal carelessly.
the result of the right people collaborating together – that’s why we need you to apply today!
🌈 Diversity & Inclusion 🌈
We want to enable exceptional experiences for everyone, and to achieve this we need everyone’s voice in our team. We are on a
mission to bring more diversity into the business and to give everyone (from all backgrounds and abilities) a chance to join us,
even if they may not fit all of the requirements set out in this job spec. We realise that some may be hesitant to apply for a
role when they don’t meet 100% of the listed requirements – we believe in potential and will happily consider all applications
based on the skills and experience you have, we’d love to be part of your growth and we encourage you to apply!
#machinelearning #machinelearningscientist #datascience #deeplearning #LLM #ML #data #AI #PyTorch #datascientist
Senior Machine Learning Scientist 🌍 UK or Poland (Remote or Hybrid, it’s up to you!) 💰 Dependent on experience 📈 Be part of our success with the opportunity to join our company equity scheme Our Perks ❤️ Monthly Health & Wellness budget, increasing with length of service 📚 Annual Learning and Development budget, increasing with length of service 🤸🏽♂️ Flexible working in a choice-first environment - we trust the way you want to work! 🖥️ Work From Home Allowance 🌴 25 Holiday Days + your local bank holidays, plus an extra day for every year of service 🎂 Your birthday off 🍼 Enhanced Family Leave (UK Only), Fertility Leave, and Neonatal Leave ⚕️ Optional Healthcare Plan 🛟 Life & income protection (Location dependent) 🤝 Employee Assistance Programme (UK Only) 📈 The opportunity to share in the company’s success through options 🌆 If you’re in London, a dog-friendly office with great classes, events, and a rooftop terrace 🦸♀️ The Role 🦸♀️ Our mission is to help large successful brands like Uber, Amazon, Wise, HelloFresh (and more!) put their customers at the centre of everything they do. Using best-in-class tech in a fast-developing AI space, our Customer Experience Intelligence platform continuously analyses explicit and implicit feedback to enable our clients to identify what they should do next. We're hiring a Senior Machine Learning Scientist to join the team and help build and ship the next generation of that stack. 👉 What you'll be doing: Unlike many companies, we use our own custom models, specialised for customer feedback, across various parts of the stack: extraction, retrieval, reranking, summarisation, and sentiment analysis. We are also pragmatic and understand that the right solution can be a combination of off-the-shelf LLMs, bespoke fine-tuned models, and sometimes techniques that utilise no LLM at all. This means you will: * Train, evaluate, and iterate on ML models and agentic systems for customer feedback, including owning our custom fine-tuning pipelines. Run experiments end-to-end, track results rigorously, and make clear recommendations on what to ship, iterate, or retire. * Build and maintain LLM-powered features: retrieval pipelines, reranking systems, insight agents, data mining agents, and automated taxonomy generation. * Design and run robust evaluation frameworks: build test sets, define metrics, evaluate non-deterministic systems, handle class imbalance, and automate checkpoint comparisons. * Improve and extend semantic search and retrieval, evolving from embedding-based approaches toward more advanced methods. * Write production-quality code and collaborate closely with Engineering on productionisation, model serving, data pipelines, and monitoring. * Work with Product and Commercial teams to translate business needs into practical ML solutions, and support client evaluations and accuracy benchmarking. * Mentor team members, review code and research, and bring relevant advances from the literature into the product. 🧰 What you’ll need: * A deep working knowledge of transformer architectures. * Strong PyTorch skills, with the ability to write custom training loops, modify model architectures, and debug issues at the tensor level. Ideally, experience with parameter-efficient fine-tuning techniques such as LoRA * Extensive experience working with large-scale, messy real-world text data, including classification, extraction, embeddings, re-rankers, clustering, and search. * Experience in instruction fine-tuning and serving language models, familiarity with frameworks such as vLLM, DeepSpeed, or similar tools * A solid grounding in classical ML and statistics, and the judgement to choose simpler methods when they’re the right solution. * Practical experience building with GenAI and agentic patterns. * Excellent communication skills and confidence translating complex technical concepts for non-technical audiences (and vice versa!). * Technical curiosity and a keen interest in AI – a love of experimenting to make the most of available technology. * High ownership and initiative, with the ability to identify problems, prioritise effectively, and drive solutions forward. ➕It would be a bonus if you: * MSc/PhD in Computer Science, Machine Learning, Artificial Intelligence, Data Science, Computational Linguistics or a closely related STEM field. * Experience with reinforcement learning techniques, such as with verifiable reward (RLVR) 🔎 Our Hiring Process 1. Let’s introduce ourselves – you’ll complete an introductory asynchronous interview - we’d love to learn more about you, your ambitions, and what you’re looking for in your next step. 2. Get to know your would-be manager – you’ll have a call with Aji, our Chief Scientist, to learn more about the role and show off your experience. 3. Show us how you work – you'll complete a short take home assignment 4. Get to know your would-be team – You'll meet a mix of people who you'll be working closely with from the Data Science, Engineering and Product teams. 5. How our values and your career goals align – you’ll have a call with our cofounder to learn more about life at Chattermill and ensure we’re the right place for your next stage of growth. 💖 Our Values * We are obsessed with experience – We take our mission to rid the world of bad Customer Experience seriously, and we practice what we preach. * We believe in the power of trust – Whether it's with each other, our customers, partners, or other stakeholders, we always communicate with openness and trust. * We act as responsible owners – Whether it's about the company, a team, a project, or a task, having the freedom to make decisions in our area of responsibility is a crucial driver for us. * We share a passion for growth & progress – On every level, we’re motivated by taking on new challenges – even if they seem out of reach. We recognise that we are learning machines and we always seek to action feedback and improve collectively. * We set our ambitions high but stay humble – We've come together to build a product and a category that’s never been seen before. While we're an ambitious bunch with lofty goals, we don't approach this goal carelessly. * We believe the right team is the key to success – At Chattermill we’ve learned that all our important achievements have been the result of the right people collaborating together – that’s why we need you to apply today! 🌈 Diversity & Inclusion 🌈 We want to enable exceptional experiences for everyone, and to achieve this we need everyone’s voice in our team. We are on a mission to bring more diversity into the business and to give everyone (from all backgrounds and abilities) a chance to join us, even if they may not fit all of the requirements set out in this job spec. We realise that some may be hesitant to apply for a role when they don’t meet 100% of the listed requirements – we believe in potential and will happily consider all applications based on the skills and experience you have, we’d love to be part of your growth and we encourage you to apply! #machinelearning #machinelearningscientist #seniormachinelearningscientist #datascience #deeplearning #LLM #ML #data #AI #PyTorch
Senior Machine Learning Engineer 🌍 UK or Poland (Remote or Hybrid, it’s up to you!) 💰 Dependent on experience 📈 Be part of our success with the opportunity to join our company equity scheme Our Perks ❤️ Monthly Health & Wellness budget, increasing with length of service 📚 Annual Learning and Development budget, increasing with length of service 🤸🏽♂️ Flexible working in a choice-first environment - we trust the way you want to work! 🖥️ Work From Home Allowance 🌴 25 Holiday Days + your local bank holidays, plus an extra day for every year of service 🎂 Your birthday off 🍼 Enhanced Family Leave (UK Only), Fertility Leave, and Neonatal Leave ⚕️ Optional Healthcare Plan 🛟 Life & income protection (Location dependent) 🤝 Employee Assistance Programme (UK Only) 📈 The opportunity to share in the company’s success through options 🌆 If you’re in London, a dog-friendly office with great classes, events, and a rooftop terrace 🦸♀️ The Role 🦸♀️ Our mission is to help large successful brands like Uber, Amazon, Wise, HelloFresh (and more!) put their customers at the centre of everything they do. Using best-in-class tech in a fast-developing AI space, our Customer Experience Intelligence platform continuously analyses explicit and implicit feedback to enable our clients to identify what they should do next. We're hiring a Senior Machine Learning Engineer to join the team and help build and ship the next generation of that stack. 👉 What you'll be doing: Unlike many companies, we use our own custom models, specialised for customer feedback, across various parts of the stack: extraction, retrieval, reranking, summarisation, and sentiment analysis. We are also pragmatic and understand that the right solution can be a combination of off-the-shelf LLMs, bespoke fine-tuned models, and sometimes techniques that utilise no LLM at all. This means you will: * Train, evaluate, and iterate on ML models and agentic systems for customer feedback, including owning our custom fine-tuning pipelines. Run experiments end-to-end, track results rigorously, and make clear recommendations on what to ship, iterate, or retire. * Build and maintain LLM-powered features: retrieval pipelines, reranking systems, insight agents, data mining agents, and automated taxonomy generation. * Design and run robust evaluation frameworks: build test sets, define metrics, evaluate non-deterministic systems, handle class imbalance, and automate checkpoint comparisons. * Improve and extend semantic search and retrieval, evolving from embedding-based approaches toward more advanced methods. * Write production-quality code and collaborate closely with Engineering on productionisation, model serving, data pipelines, and monitoring. * Work with Product and Commercial teams to translate business needs into practical ML solutions, and support client evaluations and accuracy benchmarking. * Mentor team members, review code and research, and bring relevant advances from the literature into the product. 🧰 What you’ll need: * A deep working knowledge of transformer architectures. * Strong PyTorch skills, with the ability to write custom training loops, modify model architectures, and debug issues at the tensor level. Ideally, experience with parameter-efficient fine-tuning techniques such as LoRA * Extensive experience working with large-scale, messy real-world text data, including classification, extraction, embeddings, re-rankers, clustering, and search. * Experience in instruction fine-tuning and serving language models, familiarity with frameworks such as vLLM, DeepSpeed, or similar tools * A solid grounding in classical ML and statistics, and the judgement to choose simpler methods when they’re the right solution. * Practical experience building with GenAI and agentic patterns. * Excellent communication skills and confidence translating complex technical concepts for non-technical audiences (and vice versa!). * Technical curiosity and a keen interest in AI – a love of experimenting to make the most of available technology. * High ownership and initiative, with the ability to identify problems, prioritise effectively, and drive solutions forward. ➕It would be a bonus if you: * MSc/PhD in Computer Science, Machine Learning, Artificial Intelligence, Data Science, Computational Linguistics or a closely related STEM field. * Experience with reinforcement learning techniques, such as with verifiable reward (RLVR) 🔎 Our Hiring Process 1. Let’s introduce ourselves – you’ll complete an introductory asynchronous interview - we’d love to learn more about you, your ambitions, and what you’re looking for in your next step. 2. Get to know your would-be manager – you’ll have a call with Aji, our Chief Scientist, to learn more about the role and show off your experience. 3. Show us how you work – you'll complete a short take home assignment 4. Get to know your would-be team – You'll meet a mix of people who you'll be working closely with from the Data Science, Engineering and Product teams. 5. How our values and your career goals align – you’ll have a call with our cofounder to learn more about life at Chattermill and ensure we’re the right place for your next stage of growth. 💖 Our Values * We are obsessed with experience – We take our mission to rid the world of bad Customer Experience seriously, and we practice what we preach. * We believe in the power of trust – Whether it's with each other, our customers, partners, or other stakeholders, we always communicate with openness and trust. * We act as responsible owners – Whether it's about the company, a team, a project, or a task, having the freedom to make decisions in our area of responsibility is a crucial driver for us. * We share a passion for growth & progress – On every level, we’re motivated by taking on new challenges – even if they seem out of reach. We recognise that we are learning machines and we always seek to action feedback and improve collectively. * We set our ambitions high but stay humble – We've come together to build a product and a category that’s never been seen before. While we're an ambitious bunch with lofty goals, we don't approach this goal carelessly. * We believe the right team is the key to success – At Chattermill we’ve learned that all our important achievements have been the result of the right people collaborating together – that’s why we need you to apply today! 🌈 Diversity & Inclusion 🌈 We want to enable exceptional experiences for everyone, and to achieve this we need everyone’s voice in our team. We are on a mission to bring more diversity into the business and to give everyone (from all backgrounds and abilities) a chance to join us, even if they may not fit all of the requirements set out in this job spec. We realise that some may be hesitant to apply for a role when they don’t meet 100% of the listed requirements – we believe in potential and will happily consider all applications based on the skills and experience you have, we’d love to be part of your growth and we encourage you to apply! #machinelearning #machinelearningscientist #seniormachinelearningscientist #datascience #machinelearningengineer #seniormachinelearningengineer #deeplearning #LLM #ML #data #AI #PyTorch
Location: UK Department: Engineering Employment Type: Permanent ABOUT YLD: Our goal is to help our clients keep moving forward. We work with them to build the skills and capabilities they need to stay ahead of the competition, and we know our success only happens when they succeed. We’re a team of curious, talented people, and we’re committed to making YLD a place where great people want to work, grow, and stay. We’re a remote-first consultancy specialising in software engineering, product design, and data. Our teams are based across London, Lisbon, and Porto, and we create digital solutions that continue to deliver value long after our work is done. ABOUT THE ROLE: As a Senior Software Engineer at YLD, you’ll be part of a client team building innovative products. We’re looking for someone curious, passionate, driven, and enthusiastic. You should be skilled in problem-solving and experienced in designing scalable, resilient, and fault-tolerant architectures. You’re also an effective communicator and a strong team player. Together with your team, you’ll thrive in a fast-paced engineering environment, delivering outstanding results and exciting projects. YOUR DAY-TO-DAY RESPONSIBILITIES WILL LOOK LIKE THIS: * Crafting excellent products! You will be building new features that meet the needs of our clients and customers; * Continuously delivering changes to products, as our client is moving to a full CI/CD model; * Working closely with your team, regularly collaborating and on engineering initiatives, to continually push yourselves to be better; * Learning, growing, and mentoring the engineering team to accelerate their career growth and encourage them to progress; * Working with the Lead to architect, design, build, and deliver highly available, always-on, zero downtime products; * Being responsible for the production operation and monitoring of products in line with SLAs; * Driving good practices within your team, making an impact on the whole department; * Participating in regular show and tells, promoting your work to both your department and the wider company. PREFERRED SKILLS * Proficiency in JavaScript/TypeScript, Python, and/or Go, with the ability to rapidly learn new languages; * Experience with modern frameworks across the stack (FastAPI, Gin, Express, etc.); * Production experience with React, modern build tools, state management, responsive design, and accessibility standards; * Comprehensive testing experience (unit, integration, E2E, security) and performance optimization; * Scalable system design patterns, load balancing, and high-availability architectures; * Database design and optimization (both relational and NoSQL); * API development (REST, GraphQL, gRPC) and event-driven architectures; * Caching strategies and message queue systems (Redis, Kafka, RabbitMQ); * Cloud platforms (AWS, Azure, GCP) with containerisation (Docker, Kubernetes); * CI/CD pipelines and Infrastructure as Code (Terraform, CloudFormation); * Monitoring, observability, and performance optimisation tools; * You can keep a cool head when debugging production issues; * Use AI tools to augment your work, applying sound judgement to adopt emerging technologies where they genuinely add value and increase your impact as an engineer. YOU SHOULD APPLY IF YOU ARE: * Self-motivated, proactive and always looking for ways to improve and develop yourself; * A good communicator, both in writing and verbally. You’ll be able to explain technical ideas and concepts in business-friendly language. * Detail-oriented; * Possess strong problem-solving skills that balance innovation with pragmatic technology choices to solve business needs; * Used to working in a team-oriented, collaborative environment; * Analytical and problem-solving-oriented; * A genuine believer in diversity and fairness. Benefits you’ll receive: * Company Private Health care (currently provided by Vitality) * Enhanced fully paid maternity and paternity leave for up to 6 months * 25 days annual holiday (excluding Public Holidays) * £2000 annual allowance for Training/Conferences * £300 annual allowance for additional hardware * Mental Health support: access to Oli app * Meditation/Sleep support: Headspace or Calm app subscription * Bonus (depending on Company performance and results) * Company laptop * Generous referral schemes Our typical Recruitment Process looks like this: * 1st Interview with someone from the Talent team (30/45 mins) * Technical Interview with our Senior Developers (1h30) Get a glimpse of what it's like working at YLD! 🤳 Check out our LinkedIn page We live and breathe our values, and know you will too: * Growing every day * Including everyone * Relationships built on honesty and ethics * Inspiring solutions * Winning together We’re an equal-opportunity employer and value diversity in all its forms. We do not discriminate based on race, religion, colour, national origin, gender, sexual orientation, pregnancy or maternity, age, marital status, or disability. We also offer a remote-first working environment, with flexible working and work–life balance as standard for all employees.