Senior Software Engineer IV (Python)

Company at a Glance
OpenX is focused on unleashing the full economic potential of digital media companies. We do this by making digital advertising markets and technologies that are designed to deliver optimal value to publishers and advertisers on every ad served across all screens.

At OpenX, we have built a team that is uniquely experienced in designing and operating high-scale ad marketplaces, and we are constantly on the lookout for thoughtful, creative executors who are as fascinated as we are about finding new ways to apply a blend of market design, technical innovation, operational excellence, and empathetic partner service to the frontiers of digital advertising.

We’re seeking a Senior Software Engineer with strong platform and cloud expertise to design and implement scalable integrations that enhance the performance of our platform. You’ll join a talented team to build and optimize real-time services, collaborating closely with partner engineering and product teams to deliver secure and robust solutions.

If you’re:
Open-minded - happy to give & receive feedback, not afraid to fail, and move on
Proactive - always want to find a satisfying solution
Self-organized and self-motivated
We want to talk to you.

We are operating at a scale:
100% Cloud-based (GCP) platform
Over 370 billion Ad requests every day
Over 120 000 CPU daily
Over 140 TB RAM daily
Over 50 PB of data per week
Over 1200 production deployments a month
The Team focused primarily on building audiences and segments capabilities for our platform. Our core work revolves around how audience segments are discovered, enriched, filtered, evaluated, and activated, so users can find and use the right audiences more effectively across different markets.
To support this, we work on AI-powered segment discovery, international audience targeting, contextual intelligence, and data marketplace features that help users discover, evaluate, and activate the right audiences at scale.

Our work also includes the underlying graph and data-processing foundations from household graph research to scalable 1P segment pipelines, combining product, backend, and data engineering to build ad tech solutions for a 'cookieless' future.

What we offer:
- Employment contract (22 595 - 25 254 PLN gross/monthly) OR B2B (181 - 202 PLN net/hourly)

- Working with the newest technologies such as Cloud Computing (GCP)

- Challenges at work that are difficult to find anywhere else!

- Solving important problems in a scale

- Joining a company that is growing and scaling

- Flexible working hours & remote work option

Key Responsibilities:
- Design high-performance, distributed, low-latency systems

- Architect, create and deliver new features and functionality

- Work with Product to drive the requirements, and own the project end-to-end

- Work with Engineering and Product teams distributed across multiple locations

- Analyze and improve efficiency, scalability, and stability of servers and processes

- Think long-term and be unsatisfied with band-aids

- Identify unnecessary complexity and remove it, analyze existing solutions

Required Qualifications:
- 5+ years experience with building SaaS applications using Python

- Experience with databases system design, RDBMs (MySQL, Postgres) or NoSQL

- Experience with Amazon Web Services or Google Cloud Platform

- Deep knowledge of cloud solutions, enabling the analysis of system architecture while taking potential costs into consideration (or alternatively, strong proficiency in another cloud platform).

- Experience with REST/GraphQL

- Experience with k8s, and Docker, CI/CD, SQL (BigQuery)

- Communicative Polish and English

Desired Characteristics:
- Experience with JS/TS and Java is nice to have

- Experience with Airflow and Cloud Composer

- Creating, maintaining, and modifying DAGs to orchestrate and automate data pipelines

- Experience working in digital media, marketing technology, or advertising technology is a big plus.

Our benefits (on employment contract):
- Annual performance bonus

- Tax-deductible system due to copyright protection: 75%

- Private health care for you and your family (covered by OpenX)

- Private life and travel insurance

- MultiKafeteria program

- Training: access to the LinkedIn Learning platform and Tech workshops

- Holiday Allowance

- Pension scheme (PPK from PZU)

- Additional paid day off

- Free parking lot

- Access to peer-to-peer recognition platform

- Monthly work-from-home allowance and one-time payment when you join us to help you set up your home office

- We celebrate team members' important personal milestones (vouchers, gifts)