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The company is revolutionizing e-commerce advertising by connecting post-purchase shoppers with relevant cross-sell opportunities. Our platform powers promotional ad experiences that appear immediately after checkout, helping shoppers discover complementary products while helping merchants drive incremental revenue.

We’re a seed-stage company tackling complex, 0→1 ad-tech challenges — from real-time bidding and analytics infrastructure to high-performance frontend experiences that run across millions of checkouts every day.

Responsibilities:

• Ad server and bidding logic for real-time placement optimization.
• High-performance APIs handling millions of requests.
• Analytics systems for revenue tracking and reporting.
• Integrations with major e-commerce platforms and ad networks.

Requirements:

• Tech stack: Node.js, KeystoneJS 6, PostgreSQL 16, Redis, Prisma ORM, AWS ECS, Terraform, Docker, Sentry, TypeScript.
• 5+ years in backend or full-stack development.
• Deep experience with Node.js, TypeScript, PostgreSQL, and Redis.
• Experience designing scalable APIs and optimizing queries.
• Familiarity with distributed systems, caching, and AWS infrastructure.

Mindset: Systems thinker who balances speed and scalability — you see the full architecture, not just endpoints.

Seniority level

Mid-Senior level

Employment type

Full-time

Job function

Engineering and Information Technology

Industries

Software Development

Location

Warsaw, Mazowieckie, Poland

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