This position is closed

Senior Java Developer

About the role:

Are you a Senior Java Developer looking for new challenges? What about working with a high-profile client with millions of QPS? If you have experience developing high-performance distributed systems, this is the perfect opportunity to work on a new digital marketing management platform with a world-renowned client.


4,500 - 7,500 USD



Skills & Experience:

  • Background in computer science or similar quantitative field;
  • 5+ years of professional software development experience;
  • Expert Knowledge of Core Java;
  • Experience developing high scale and high performance distributed systems;
  • Good understanding of algorithms, data structures, performance optimization techniques, object-oriented programming, multi-threading, and real-time programming;
  • Product-focused mindset;
  • Team player with strong interpersonal skills;
  • English — Upper-intermediate or above.

Nice to have:

  • Experience with cache optimization, distributed cache, and NO SQL DB is a plus;
  • Experience with Big Data and AWS services is a plus;
  • Experience in the advertising domain is a big plus.


  • Work with a highly skilled engineering team in all phases of the Agile development process, from design to deployment;
  • Design, develop, and maintain a high scale, high-performance real-time application;
  • Work with quality assurance, release engineering, and product management to deliver quality software;
  • Identify, design, and implement improvements to the current architecture. This may include: improving internal processes, automating manual processes, optimizing data delivery, reducing cost, re-designing infrastructure for greater reliability, etc;
  • Take your own initiative in the development process and working atmosphere improvements, be proactive in suggesting new vision and approaches to the platform development; anticipate problems or issues solutions that may arise;
  • Deliver constant value back to the business in a highly agile team approaching near-continuous deployment.


  • Flexible working hours;
  • Direct communication with C-levels;
  • Collaborative, friendly team environment
  • Remote/hybrid work;
  • Company equipment provision;


  • Maternity and paternity leaves;
  • Proxet Cultural Club events;
  • Company social events;
  • Annual corporate parties;


  • Comprehensive medical insurance and sports benefits;
  • Mental health program with private consultations;
  • Live webinar with therapists;
  • Paid sick leaves;


  • Allowances for professional education;
  • English language courses with native speaker;
  • Internal knowledge-sharing sessions.

project tech-stack

Aerospike, Amazon, Apache Mina, Avro, Big Data, Concurrency, Java11, Lucene, Netty, Scala, Tomcat

About the Project

Roku Demand Side Bidding (aka DSP/RTS) DataXu is an omnichannel media management platform, which uses powerful machine learning algorithms to automate media and optimize campaign results — a large part of the system built and supported by Proxet (formerly RailsReactor). DataXu came to us in 2010, when their growth compelled them to augment their engineering team with expert external assistance. The DataXu platform is a highly scalable, low-latency system that evaluates opportunities to bid in auctions for ad space in real-time. In peak traffic, it handles in excess of 2.5 million requests per second with a 95th percentile latency in the tens of milliseconds and is integrated with dozens of ad exchanges. Functionality Includes:

  • Active Analytics. This mixed media solution uses machine learning and predictive analysis to test ad investment patterns, analyze investment against projected outcomes, and optimize media mix across online and offline media down to the region.
  • Detailed Customer Insights. Access detailed customer insights, including age, geographic location, previous brand interaction, and purchase intent behavior. You can also use the report builder feature to visualize the information that’s important to you and your business
  • Marketing Plan Benchmarking. Allows the user to analyze an existing marketing plan for performance and improvements
  • OneView — ability to sync user information across all their devices
  • People Based Marketing —  complete picture of a customer’s journey through the sales funnel
  • Automated Bidding Component. Currently, the automated bidding component handles over 500k requests per second and applies all logic within 15 milliseconds
  • Fraud Protection Module.  DataXU uses the most advanced fraud protection currently on the market, ensuring effectively automated ad purchases

About the Client



Company size:

1,650 (2021)


1.78 Billion USD (2020)


Roku is a leading streaming service based in the United States. With millions of users worldwide, Roku devices provide easy access to free TV, live news, sports, movies, etc. Roku has an advertising business and also licenses its hardware and software to other companies.


Who you will be working with

Meet you future colleagues:

Backend engineer with 10+ years experience of distributed system design and development . Skilled at caching solutions. Have hands-on experience of up to 7 people team management.

Senior Java Developer

About Proxet

company information:

Proxet is a professional software development firm trusted by clients from around the world. With our expertise in AI and machine learning, we help businesses reimagine their possibilities and transform ideas into tangible digital solutions. By providing core services with an emphasis on data practices, we shape the future, one step at a time. 

If you’d like to join our Proxet Nation and work closely with high-level professionals and our engineers, fill in the form!

Company benefits

  • Work-from-home policy (fully remote option)

  • Insurance coverage and paid sick leaves

  • In-house English classes with native speaker

  • Trainings allowance based on eligibility conditions plus professional certification paid by the company

Our Offices:

Interested in this closed position?

Leave the information about yourself and we will contact you when we have suitable vacancies!


    Inna Nesterenko

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