Java Back-End Developer

Adxe is a global company developing an AI-powered programmatic DSP platform. Our bidder processes OpenRTB requests from major exchanges (Xandr, Google, Pubmatic, OpenX, Index) with <100ms response times at millions of QPS.

We're looking for a Java Developer with back-end expertise to join our core engineering team. This is a fully remote position working on high-performance, real-time bidding systems.

What You'll Do

• Become a key member of our core R&D team building the bidder and MissionControl systems

• Work on our 13-step bid processing pipeline with tree-based targeting index (163+ dimensions)

• Build and optimize OpenRTB bid request/response handling with Undertow (NIO)

• Develop campaign management APIs (CRUD for campaigns, line items, creatives, audiences)

• Focus on scalability & performance for systems processing millions of requests per second

• Integrate ML model inference (LightGBM) for real-time CTR prediction

• Implement budget management with overspend prevention

• Take full ownership of features from design to deployment

Required Experience

• 3+ years of experience in server-side development for high-load products

• Proven experience in Java programming (Java 22 preferred), including Java Concurrency – Must!

• Experience with high-performance HTTP servers (Undertow, Netty) – Must

• Experience with MongoDB – Must

• Familiarity with Ad-Tech industry / DSP platforms / OpenRTB – significant advantage

• Experience with at least one: ClickHouse, Aerospike

• Familiarity with React/TypeScript for occasional frontend work – advantage

• Proactive, highly motivated individual with strong work ethic and sense of ownership