Key Responsibilities:  

• Design, build, and own back-end services in Python that power the Fulfillment platform: APIs, document workflows, and data processing pipelines  

• Lead design work on non-trivial features: propose architectures, weigh trade-offs, write and review design documents, and drive decisions to closure with the team  

• Build and evolve event-driven and asynchronous processing (streams, queues, scheduled jobs) supporting EDI document workflows at high volume  

• Contribute across the stack including React/TypeScript front-end work so that features ship end-to-end rather than stopping at a service boundary  

• Model and optimize relational data: schema design, query performance, migrations, and partitioning strategies on large production datasets  

• Improve reliability and observability: participate in on-call and incident response, reduce alert noise, and drive the resolution of recurring production issues  

• Raise the engineering bar through code review, pairing, and mentoring of mid-level engineers  

• Partner with product management, UX, and QA to turn business requirements into maintainable solutions, and with adjacent teams on cross-service dependencies  

• Work AI-first: use AI engineering tools as a default part of the delivery loop, and actively improve how the team applies them like shared tooling, prompts and skills, agentic workflows, and sensible guardrails 

Required Qualifications:  

• 6+ years of professional software engineering experience, with demonstrable ownership of production systems 

• Deep Python expertise for back-end services like Django/DRF, FastAPI, or equivalent — including API design and testing practices 

• Strong relational database skills: schema design, indexing, query optimization, and migrations (PostgreSQL/Aurora, MySQL, or Oracle) 

• Asynchronous and event-driven experience: message queues or streaming (Kafka, Kinesis, SQS/SNS, RabbitMQ) and background task processing (Celery or similar) 

• Cloud experience, AWS preferred (or Azure/GCP with willingness to work in AWS) 

• Design and technical leadership: has driven a meaningful feature or system from ambiguous requirements through design, delivery, and operation 

• Working experience with React and TypeScript or another modern component framework (Vue, Angular) plus a genuine willingness to work in React 

• Production ownership: on-call participation, debugging live incidents, and improving reliability afterwards 

• Solid engineering hygiene: Git, CI/CD, automated testing, code review 

• Comfortable in an Agile/Scrum team and in a distributed setting across time zones 

• Professional working proficiency in English, written and spoken 

• Fluent, daily hands-on use of AI engineering tools (Claude, GitHub Copilot, Cursor or similar)  

  
Preferred Experience:  
  

• Experience with data/analytics pipelines (CDC, warehouse or lakehouse platforms such as Databricks/Snowflake) 

• Exposure to EDI standards or the supply chain / B2B commerce domain 

• Containerization and orchestration (Docker, Kubernetes) and infrastructure-as-code (Terraform) 

• Observability tooling (Grafana, Prometheus/VictoriaMetrics, Sumo Logic) and pragmatic alerting design 

• Search and caching technologies (OpenSearch/Elasticsearch, Redis/ElastiCache) 

• Experience mentoring engineers formally or acting as a tech lead 

• Building LLM-powered product features, agentic tooling, RAG pipelines, or MCP integrations in production represents a significant differentiator for this role 

• Open-source contributions or side projects demonstrating technical depth 

Location:  

This role is in our Warsaw office, Poland and the team is in-office 1 day per week.  

  
What We Offer:  

SPS Commerce is the world’s largest retail network, connecting 120,000+ businesses — real impact at scale 

Fulfillment is a core product with direct business impact — not a side project or experimental team 

Modern tech stack (Python, React, TypeScript, AWS) with room to influence architectural decisions 

AI-forward engineering culture - the team actively uses Claude and Copilot in daily work, with growing opportunities to build AI-powered product features 

Hybrid work model with office presence in Poland — flexibility plus in-person collaboration 

Opportunity to work on complex data workflows (EDI, supply chain automation) that most engineers never encounter 

Collaborative, non-hierarchical engineering culture - all ideas are heard, knowledge-sharing is fast and organic, and bureaucracy is minimal