Principal Software Engineer

OpenX - Principal Software Engineer

What we offer:

• Employment contract (29 608 - 33 090 PLN gross/monthly)
• 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:

• Lead the architecture and technical vision for platform integrations, ensuring high performance, security, and scalability.
• Design and build systems that enable partners to connect and operate real-time services efficiently and securely.
• Work with partner engineering and product teams to plan, build, and launch integrations that meet business and technical goals.
• Deliver critical platform features from design through implementation, testing, rollout, and adoption.
• Identify and address technical debt, performance bottlenecks, and scalability risks before they impact customers.
• Champion architectural patterns and platform capabilities that improve developer velocity and operational reliability.
• Promote engineering excellence through constructive code reviews, mentoring, and driving improvements in code quality, architecture, and platform best practices.

Required Qualifications:

• 12+ years of professional software development experience, with deep expertise in Java and/or Go (both preferred).
• Hands-on experience with a major cloud platform (GCP, AWS, or Azure) for designing and operating production workloads.
• Proven track record of delivering large-scale, high-performance, and reliable systems.
• Expertise in RESTful API design and scaling, including data modeling, error handling, performance optimization, and security best practices.
• Strong background in distributed systems, Kubernetes, and containerized services.
• Experience leading architecture and technical direction across multiple teams or product areas.
• Strong problem-solving skills, with the ability to anticipate and address scalability, reliability, and privacy challenges.
• Excellent collaboration and communication skills, with success working closely with product, partner engineering, and cross-functional stakeholders.
• Proven ability to mentor senior engineers and raise technical standards across an organization.

Desired Characteristics:

• Experience designing real-time, low-latency, large-scale data processing systems.
• Knowledge of programmatic advertising or other high-throughput transactional platforms.
• Familiarity with CI/CD pipelines, infrastructure as code (Terraform, Helm), and advanced monitoring/observability tools (e.g. Grafana).
• Proven ability to introduce architectural patterns that improve developer velocity and system reliability.
• Experience using AI-assisted development tools to enhance productivity.

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)