Senior Computer Vision Engineer- UK

About Us: STACK is a leading provider of cloud-based construction estimating and takeoff software solutions, committed to helping businesses transform through innovative solutions. We pride ourselves on fostering a collaborative, dynamic environment where team members have the opportunity to grow and make a real impact. About the Role: We are hiring a Senior Computer Vision Engineer to improve our computer vision system for construction documents. This role focuses on detection and segmentation quality, geometric accuracy, and production-grade pipelines that work reliably with messy real-world PDFs and drawings. What You’ll Do: - Design, build, and improve end-to-end detection and segmentation pipelines for document images. - Improve document ingestion for PDFs and other unstructured files, including parsing, rendering, and handling of multi-page and multi-view content. - Increase model accuracy, boundary and geometric quality, and overall reliability of predictions for downstream use. - Integrate modern detection and segmentation models into production workflows and build the post-processing that turns model output into structured, usable geometry. - Define evaluation metrics, investigate failure cases, and drive continuous quality improvements. - Optimize latency, reliability, and cost across the inference and post-processing stack. - Own training infrastructure, dataset curation, annotation quality, and continuous-improvement loops. - Make architectural decisions and own system quality end to end. What You Bring: - 5+ years experience building computer vision systems: detection, segmentation, or structured geometry extraction, used high volume in production. - Experience working with messy, real-world image data or large unstructured visual datasets. - Strong understanding of detection and segmentation tradeoffs, including model architecture choices, training data design, and post-processing. - Ability to measure system performance with evaluation, testing, and production metrics. - Ability to explain failure modes clearly and improve systems through debugging, dataset work, and iteration. - Experience with multimodal models (vision-language models, document AI systems) - Understanding of grounding — linking model outputs to source data or coordinates - Backend engineering experience, including APIs, async processing, and scalable GPU services. Additional Preferred Qualifications: - Experience with polygon or mask post-processing, geometric regularization, or CAD-style structured output. - Experience with layout-aware document processing, PDF vector extraction, or combining raster and vector signals. - Background in document-heavy CV domains such as construction, real estate, medical imaging, geospatial, or similar workflows. - Experience optimizing inference cost and latency at scale. - Familiarity with open-source detection / segmentation ecosystems, training infrastructure, or model serving. What Success Looks Like: - Accurate, geometrically correct predictions suitable for downstream measurement, and analysis use. - Fast, reliable inference across large and messy real-world document sets. - Clear quality metrics and a repeatable improvement loop. - Systems that perform consistently under real-world production constraints. What This Role is Not: - Not a model-training-only role. You'll own data, training, post-processing, and serving. - Not a research-only role. - Not a plug-and-play CV tools environment. Why Join STACK? - Opportunity to work in a fast-paced, growth-oriented, remote-first environment. - Async-friendly environment with a focus on ownership and deep work. - Be part of a dynamic, supportive team where your contributions are valued. At STACK, our values shape how we work, collaborate, and serve our customers: - Radical Honesty:Communicate directly, respectfully, and transparently—even when conversations are difficult. Give and receive feedback with care. - Cust