Senior Software Engineer, Data

PlayOn! Sports; Poland; On-site; PLN 300,000 - 420,000; Full time

Benefits offered by this job

Hybrid/flexible work environment

Company equity (stock options)

Open PTO policy

401K plan with company match

Medical insurance

Dental/vision/life

Job summary

PlayOn! Sports is seeking a Senior Software Engineer to build AI-powered, data-driven services for web experiences used by millions of high school sports fans.

You will join a product team delivering backend features, data modeling, and LLM integrations that power applications and AI-driven experiences. The role emphasizes end-to-end ownership from architecture to observability, with front-to-back responsibility for performance and reliability across the stack.

Qualifications

• 5+ years of professional software engineering experience with backend web applications.
• Experience building production features backed by LLMs or AI integrations.
• Hands-on cloud data warehousing experience (Snowflake or similar).
• Strong skills in C# .NET, Python, SQL, and data modeling.
• Experience with AWS deployments and CI/CD pipelines.
• Knowledge of evaluation frameworks for AI systems and regression detection.
• Solid PostgreSQL experience with performance tuning and data modeling for AI access.

Responsibilities

• Develop AI-powered, data-driven backend features and services grounded in PlayOn data.
• Build and maintain APIs and backend services serving apps and LLMs.
• Design evolving data schemas that support traditional APIs and AI access patterns.
• Own features end-to-end: architecture, implementation, testing, observability, and ops.
• Plan migrations, platform upgrades, and modernization with minimal risk.
• Monitor PostgreSQL workloads and optimize query performance and indexing.
• Define eval suites for production AI features and integrate into CI pipelines.

Skills

Backend development

C# .NET

Python

SQL

REST API design

Data modeling

AWS

PostgreSQL

CI/CD

Git/GitHub

Agile teamwork

Education

Bachelor’s in Computer Science or equivalent

Tools

Snowflake

PostgreSQL

GitHub

REST APIs

Job description

PlayOn is looking for a Senior Software Engineer to develop AI-powered, data-driven services and features for web experiences used by millions of high school sports fans. This role is embedded in a product development team and combines strong backend delivery ownership with hands‑on work on the data, APIs, and LLM integrations that power them.

You’ll partner closely with product and engineering teams to shape how our sports data is modeled, defined, and exposed to both applications and LLMs, and build the systems that bring those features to our audiences.

The outcomes you’ll deliver

• Ship AI-powered, data-driven features and experiences grounded in PlayOn’s data
• Build, maintain, and improve APIs and backend services
• Design and evolve data schemas and APIs that make our sports data accessible to both application code and LLM‑driven features
• Drive technical decisions for the features you ship, and contribute to performance and operational health across the application
• Establish eval and observability practices for AI features so regressions are caught in CI rather than by users

In this role, you can expect to

• Develop modern backend services using C# .NET, Python, SQL, AWS, and Snowflake
• Build LLM‑powered features against PlayOn’s data, connecting models to Postgres, Snowflake, and internal APIs via retrieval, tool use, and semantic search
• Model and evolve data schemas so they serve both traditional APIs and AI‑driven access patterns
• Own features end‑to‑end: architecture and design, implementation, testing, observability, and operational readiness
• Plan and execute backend migrations, platform upgrades, and modernization initiatives with minimal risk
• Optimize and monitor PostgreSQL workloads, including query performance, indexing, and database health trends
• Define and maintain eval suites for production AI features (retrieval quality, answer accuracy, and regression detection) wired into CI

To thrive in this role, you have

• 5+ years of professional software engineering experience, including backend web application development
• Experience building production features backed by LLMs, such as RAG, semantic/vector search, or tool use / function calling
• Hands‑on experience with cloud data warehouses (Snowflake or similar)
• Strong expertise in C# .NET, Python, SQL, REST API design, and data modeling
• Working knowledge of AWS for deploying and operating backend services
• Experience building eval frameworks for AI systems, including golden sets, LLM-as-judge, and regression detection, applied to production AI features and/or agentic dev workflows
• Solid PostgreSQL experience, including schema design, query tuning, and modeling data for both transactional and analytical/AI access patterns
• Experience with CI/CD pipelines, automated testing, and Git/GitHub workflows
• Ability to work effectively in a collaborative, agile, team‑oriented environment
• Bachelor’s in Computer Science or equivalent experience preferred

You Might Also Have

• Proficiency with load testing, observability, and reliability engineering practices
• Experience working on high‑traffic public‑facing websites
• Experience with vector databases or vector search
• Experience exposing data and tools to LLMs via function calling, MCP, or agent frameworks
• Knowledge of or interest in sports, sports management, and statistics

How You Play

• Ownership over Participation-You take responsibility for achieving holistic outcomes, prioritize key objectives, and adapt quickly when situations require a different approach. You follow through even against the toughest challenges.
• Team over Stars-You are a bridge builder, establishing processes and relationships with teams outside your own. You work to rally around common goals, find win‑win solutions, compromise when necessary, and help others succeed.
• Growth over Comfort-You are driven by a desire to grow and actively seek opportunities to expand your comfort zone, skills, and confidence. You embrace new challenges with curiosity, accepting discomfort and failure as opportunities to learn.
• Fairness over Popularity-You approach decisions with a scientist’s mindset, challenging your assumptions and remaining objective. You consider long‑term impact rather than relying on short‑term gains, proactively seek others’ perspectives, and manage emotions in decision‑making.

PlayOn is where high school sports come to life. Through GoFan, NFHS Network, and MaxPreps, we give every fan a front‑row seat to the moments that matter most: the buzzer‑beaters, the comeback wins, the senior nights, the rivalries that define a town.

We built our technology for the people who live and breathe high school athletics — the parents who never miss a game, the alumni still cheering from across the country, the communities that show up week after week. From buying tickets to watching a live stream to reliving the highlights, we make it simple to stay close to the sports and the athletes you love most.

Backed by KKR, we build the technology that powers high school athletics from the inside out: Schools trust us to handle ticketing, streaming, fundraising, concessions, merchandise, and more so the people running programs can stay focused on the athletes and fans we all serve together.

We're a growth‑stage company on a mission to make high school sports more accessible, more memorable, and more connected than ever before.

When being there means everything, we make sure you never miss a moment.

Why You'll Love Working at PlayOn

Product, potential, and people. We’re a leader in the high school event space, constantly evolving our product to meet the needs of administrators. We focus on solving real challenges, learning quickly, and creating impactful solutions.

This is a growth‑stage company, meaning your contributions have real impact. You’ll have opportunities to grow your skills, tackle meaningful problems, and make a difference in the lives of schools and the students and fans they serve.

Our culture is built on accountability, collaboration, growth, and fairness. We don’t just show up—we show up for each other. Everyone wears the same jersey, and we play hard, make the extra pass, and cheer one another on. Losses teach us, challenges motivate us, and persistence drives us forward. We value integrity over shortcuts, choosing to do what’s right even when it’s hard. Together, we strive to be better every day—because we know that’s how we win as a team.

The Benefits We Offer

Multiple medical insurance plans to choose from

Dental, vision life and disability insurance

Employee Emergency Fund

Company equity (stock options)

Open PTO policy

401K plan with company match

Hybrid/flexible work environment

Note: Must be a full‑time employee to participate in the company’s employee health benefit plan. Part‑time employees and interns are not eligible to participate