Senior Software Engineer

Lengow is a leader in intelligent e-commerce solutions that help brands and retailers drive profitable growth across the digital shelf. With powerful feed management, global price monitoring, and robust data capabilities, Lengow’s comprehensive SaaS product suite enables merchants to amplify product visibility online, outrun competition with informed pricing, multiply sales on marketplaces, and monitor brand presence among distributors. Since 2009, Lengow has fueled digital growth for over 3,600 customers across thousands of marketing and sales channels in over 60 countries.

Lengow is a profitable company.

About the team

The Market Intelligence team builds products that turn large amounts of public web data into actionable market intelligence for our customers. We help businesses monitor prices, sellers, and market changes, identify pricing opportunities, and ensure compliance with commercial and contractual requirements. At the same time, the team is modernizing the underlying platform to make it more scalable, modular, event-driven, and asynchronous, enabling us to build and deliver new products faster.

What you'll do

• Join the Market Intelligence team, working alongside Senior Software Engineers and Software Engineers.
• Design, build, and maintain new products and features for our clients, in close collaboration with the Engineering Manager and Product Manager.
• Explore and develop AI-based solutions, using ML/DL models and LLMs to generate insights, solve complex problems, and automate or improve product capabilities.
• Take ownership of projects from discovery and technical design through implementation, delivery, and continuous improvement.
• Contribute to the modernization of our legacy codebase, progressively moving towards a more modern, scalable, event-driven, and asynchronous architecture.
• Work on systems that process and leverage large amounts of public web data to generate actionable insights and intelligence for our customers.
• Collaborate closely with other technical teams, including User Experience, Infrastructure, and Data, as well as with Support and Customer Success Managers (CSMs) when needed, to understand customer needs and solve complex problems.
• Help improve the team's engineering practices, architecture, and technical standards, while sharing knowledge and mentoring less experienced engineers.
• Contribute to products that help our customers:
• Optimize product prices and remain competitive.
• Monitor seller compliance, including branding, product images, and other requirements.
• Monitor contractual compliance, such as whether sellers respect agreed pricing conditions.
• Track product prices and market changes to provide a clear view of the competitive landscape.

Must have

• Senior-level software engineering experience, with a strong track record of designing and delivering production-grade software.
• Experience using AI coding agents as part of the software development workflow, with the ability to effectively review, validate, and improve AI-generated code.
• Experience with cloud infrastructure and distributed systems, including technologies such as Kubernetes, queues (e.g. Celery), Redis, and similar tools.
• Experience building and maintaining SaaS applications in a production environment.
• Strong software engineering fundamentals, including writing maintainable, testable, scalable, and well-structured code.
• Experience with Domain-Driven Design (DDD) and designing modular, domain-oriented systems.
• Professional proficiency in English, both written and spoken.

Good to have

• Strong experience with PHP and/or Python.
• Experience in eCommerce, Retail, or Price Comparison.
• Experience working in an Agile development environment.
• Experience with, or a strong interest in learning about and tackling challenges involving AI and machine learning, including ML/DL models and LLM-based solutions.
• Experience with microservices or service-oriented architectures.
• Experience modernizing and modularizing legacy applications, including progressively extracting functionality into independent services.
• Experience applying DDD principles to legacy codebases and large-scale refactoring.
• Experience with Kubernetes migrations or cloud-native architectures.

Why Join Lengow?

Benefits & Working Conditions

• Working Hours : Monday to Thursday from 9 am to 6 pm, Friday from 9 am to 3 pm.
• Environment : Fast-growing tech company, young and international team.
• Learning & Development : Opportunities for quick career growth.
• Company Perks :
• Gym membership discounts via Wellhub.
• Private health insurance discounts.
• Free organic fruit and coffee.

Location : Barcelona - Office with 360º views of the city.