Integration Engineer - Machine Learning - OneRail’s Technology Hub - Poland

Integration Engineer - Machine Learning
OneRail is a technology company innovating solutions for multi-modal delivery. We have built and continue to develop a delivery orchestration platform that connects shippers to an extensive courier ecosystem to automate, optimize, and control the entire delivery supply chain, from the demand signal to the proof of delivery.  
Our OmniPoint SaaS platform uses proprietary algorithms and artificial intelligence to power efficient same-day delivery programs for major companies like Lowe’s, Pepsi, American Tire Distributors, and Advance Auto Parts.
We’re seeking a dedicated Integration Engineer whose primary focus will be integrating machine learning models into our flagship product. You’ll bridge the gap between data science and production software—implementing, deploying, and maintaining ML-powered features while contributing to back-end services and React-based front-end components. Your work will enable seamless, scalable AI capabilities for end users.
Key Responsibilities:

• Work with ML pipeline engineers to deploy and maintain ML models (e.g., PyTorch, scikit-learn) as robust service endpoints.
• Collaborate with data scientists and product to productionize prototypes, and extend the product to enable ML and AI features.
• Define and evolve RESTful APIs with OpenAPI/Swagger—ensuring they support low-latency, high-throughput ML inference.
• Version, document, and maintain API contracts for internal and external consumers.
• Build microservices (Python—FastAPI/Flask—or Node.js) that encapsulate ML logic, data pre/post-processing, and business rules.
• Optimize service performance, scalability, and reliability (caching, async processing, batching).
• Implement and modify React components and pages to expose ML-driven functionality
• Ensure seamless data flow from back end to front end, handling streaming or polling as needed.
• Containerize ML services (Docker) and orchestrate deployments
• Work closely with cross-functional teams (data science, product, QA) to translate ML requirements into production features.
• Champion code quality, API versioning strategies, and thorough documentation.

Requirements:

• 3+ years of professional full-stack development, with a clear track record of integrating ML into production systems.
• Hands-on experience serving models in production (model serialization, serving frameworks, inference optimizations).
• Strong TypeScript and Python proficiency
• Experience with microservices architecture, message brokers (Kafka wtc), and async frameworks
• Solid React knowledge (hooks, context, state management);
• Deep understanding of REST principles, OpenAPI/Swagger, and API versioning/Backward-compatibility.
• Docker and orchestration experience.
• CI/CD pipelines (GitHub Actions, Jenkins, GitLab CI) and automated testing (unit, integration, e2e).
• Strong communicator, able to translate technical concepts for non-technical stakeholders.
• Excellent problem solver with an eye for scalable system design.
• Advanced proficiency in English, both written and spoken (B2+).

Not sure if you have enough experience to meet the challenge, but still willing to learn and join our team? Send us your application and we will be happy to talk about the possibilities. Think big!

Why Join OneRail Poland?

• Innovation at its Core: Work on industry-leading technology that is shaping the future of logistics.
• Career Growth: Opportunities for professional development and career advancement.
• Collaborative Culture: Join a team of talented engineers and industry experts.
• Exciting Challenges: Solve complex problems and contribute to impactful projects.
• Flexibility: We offer a flexible hybrid work style and flexible employment types to suit your needs, ensuring a work-life balance that works for you.
• Competitive Compensation: Attractive salary and benefits package.

Office location: Kraków, Poland
Work Style: hybrid (2-3 days from the office / week preferred), We are open to a more flexible arrangement for candidates located outside the Krakow area.
Salary level: 20 000 – 27 000 PLN/ month
Take the next step in your career and become a part of OneRail’s exciting journey!
 

About OneRail

OneRail is a leading omnichannel fulfillment solution pairing best-in-class software with logistics as a service to provide dependability and speed to help businesses meet their delivery promise. With a real-time connected network of 12 million drivers, OneRail matches the right vehicle for the right delivery so brands lower expenses and increase capacity to rapidly scale their businesses. This people-plus-platform approach features a 24/7 USA-based exceptions team who maintain a 98% on-time delivery rate. By optimizing fulfillment processes, reducing costs and improving order accuracy with store-shelf-to-doorstep visibility, OneRail is committed to empowering clients and improving the customer experience.

OneRail was named to the Deloitte Technology Fast 500™ two years in a row, was ranked 19th in the 2025 FreightTech 25, named for the fifth year in a row to the FreightTech 100, was honored as one of Inc. magazine’s Best Workplaces 2023, was listed on Forbes’ lists of America’s Best Startup Employers for the last three years, was named to the Inc. 5000 two years in a row and was selected as the Last Mile Company of the Year for the 2024 SupplyTech Breakthrough Awards. To learn more about OneRail, visit OneRail.com.