Remote Backend Engineer, Ads Platform

Whatnot; Kraków; On-site; PLN 180,000 - 280,000; Full time

Job summary

Whatnot is building the future of live commerce. We are hiring a Backend Engineer to help shape ads systems, scale backend services, and own end-to-end delivery with a product-minded focus. You will work across the ads stack, collaborating with product, design, and data teams to deliver high-impact features.

Join a fast-moving team that values ownership, customer outcomes, and robust engineering practices while supporting a remote-first culture with international collaboration.

Qualifications

• Bachelor’s degree in Computer Science, a related field, or equivalent practical experience.
• 4+ years of professional software engineering experience building and shipping backend systems in production environments.
• Strong experience designing, building, and operating scalable, maintainable backend services.
• Strong technical judgment and the ability to make thoughtful tradeoffs between speed, quality, reliability, and long-term maintainability.
• Experience working in fast-moving, cross-functional product or platform environments.
• Comfort owning ambiguous problem spaces and turning them into clear technical plans and shipped outcomes.
• Strong communication and collaboration skills, especially when partnering across engineering, product, design, and data.
• A product‑minded approach to engineering — you care not just about whether a system works, but whether it creates value for users and partner teams.

Responsibilities

• Build ads products by working across the full ads stack including bidding & targeting, ranking/auction, serving, campaign management, and seller tooling.
• Build highly scalable ads systems that handle all aspects of running an online advertising system and help sellers differentiate themselves on Whatnot.
• Dig deep into data, logging, and system behavior to reason about performance, correctness, and impact — not just ship features, but understand why they work.
• Understand our buyer and seller experiences and become an expert in helping them effectively scale their business through ads products.

Skills

Backend engineering

System design

Scalability

Cross-functional

Technical judgment

Communication

Product-minded

Education

Bachelor's degree in Computer Science or related field

Job description

Whatnot is building the future of live commerce. We are hiring a Backend Engineer to help shape ads systems, scale backend services, and own end-to-end delivery with a product-minded focus. You will work across the ads stack, collaborating with product, design, and data teams to deliver high-impact features.

Join a fast-moving team that values ownership, customer outcomes, and robust engineering practices while supporting a remote-first culture with international collaboration.