Fullinfo is looking for a Senior Machine Learning Engineer who enjoys turning messy web data into structured, reliable company intelligence.This is not a research role, management track or career step for people who mainly want to move up. It is a hands on engineering role for someone who gets satisfaction from solving complex data problems properly.About usFullinfo is a self funded software company building a B2B company intelligence platform.We continuously crawl the open web and turn unstructured company websites, directories, registries and industry sources into clean, searchable company profiles. The result is a global database where users can search for specific company data and actually get the right answer.The product helps sales and marketing teams search across company data in a way that feels simple on the surface, but is technically complex underneath. Think natural language search, structured filters, company enrichment, relationship detection and reliable classification across many countries, industries and languages.Fullinfo currently works with a compact team of around 11 people, including backend engineers, frontend engineers, UX UI designers, DevOps and machine learning specialists. The team is small, international and focused on people who actually build, improve and ship the product.The culture is calm, direct and quality driven. People say what they do and do what they say. There is little room for ego, politics or vague ambition talk. The best fit is someone who is quietly driven, technically strong and genuinely interested in building something that works well.This is not the environment for people who constantly reinvent their profile, chase the next title or need a lot of structure around them. It is a strong fit for stable engineers who know their craft and like working with other people who take quality seriously.Role descriptionAs Senior Machine Learning Engineer, you will work on the intelligence layer at the heart of Fullinfo's product.Your work turns raw, noisy and unstructured web content into trustworthy data points. This includes things like industry classification, company maturity stage, tech stack, geography served, corporate hierarchy, entity matching and relationship detection.You will write Python, build and improve ML pipelines, integrate LLMs, evaluate model quality and make sure the system keeps producing accurate results at scale.The stack includes Python, Pandas, scikit learn, Transformers, boto3, AWS Lambda, SageMaker, S3, ECS, Terraform, Go and TypeScript.You will work closely with a small engineering team, but this is not a role where someone tells you every step to take. The direction is clear, the expectations are high, and the work needs to be done properly. You need to be comfortable figuring things out, validating assumptions and improving quality without needing constant confirmation.Your work includes:• Designing and improving models for classification, entity resolution and relationship detection• Working with noisy web scraped data across many languages and formats• Building ML pipelines that run reliably in production• Using LLMs for extraction, enrichment, validation and search related use cases• Working with embeddings, RAG, fine tuning and prompt engineering where it actually adds value• Defining evaluation metrics so model quality is measurable instead of based on gut feeling• Monitoring deployed models and improving them over time• Working with AWS services such as Lambda, SageMaker, S3 and ECS• Collaborating with backend engineers on production systems and data flowsThis role is a strong fit for someone who enjoys deep technical problems more than status. Someone who would rather fix a broken classification result than talk about building a team under them.RequirementsYou bring:• At least 5 years of hands on ML engineering experience• Strong Python skills• Experience with libraries such as Pandas, scikit learn, Transformers and boto3• Real production experience with ML on AWS• Experience with LLMs, embeddings, RAG, prompt engineering or fine tuning• Comfort working with large scale, messy and semi structured data• Experience with JSON, NoSQL data and scraped web content• A strong eye for correctness and data quality• Business level English• The ability to work independently in a small remote team• A stable track record that shows depth, consistency and ownershipConditions• 12 month B2B contract• Fully remote work (GMT -3), you are allowed to have a 3 hour overlap• Flat structure with direct communication• Production product with real users and real data problems• Strong technical challenge around ML, LLMs, search and company intelligence• Compensation based on senior contractor levelThe hiring process includes an intro call, a technical assignment and a final conversation with the engineering team.Interested? Apply trough the link and get in touch with our consultant LarsFullinfo is exclusively partnering with Haystack People for this role. They will support you throughout the process and handle the initial screening, focusing on both your relevant experience and the soft skills that match Fullinfo's needs.