Python Developer

Quick Facts

• Role: Python Developer (Data Engineering)

• Domain: Bank revenues management and stock reconciliation

• Environment: Multi-cloud (AWS and GCP)

• Collaboration: Hybrid (coordination meetings in Warsaw ~2x/week)

Description

You will work on a critical banking application for revenues management and stock reconciliation, processing very large datasets in a multi-cloud environment (AWS and GCP). The work covers Python-based ETL/ELT pipelines, optimized PostgreSQL SQL for large/partitioned tables, and production troubleshooting to ensure continuous operation. You will also take over technical knowledge and responsibility for the solution from the previous team in Spain.

Responsibilities

• Co-create and develop the critical banking application for revenues management and stock reconciliation
• Design, develop, and maintain ETL/ELT pipelines in Python (Pandas, Polars) processing data at the scale of billions of records
• Write and deliver efficient, optimized SQL queries in PostgreSQL, including for partitioned and very large tables
• Diagnose and fix production issues across multiple systems and data sources
• Improve performance and scalability of data processing workflows in AWS/GCP multi-cloud
• Transfer knowledge and assume technical ownership of the solution from previous providers in Spain

Requirements

• Minimum 5 years of commercial experience in a Python Developer or related data role (Data Engineer/Data Developer/Data Scientist/Analytics Engineer or similar)
• Excellent Python skills with practical commercial experience building and evolving Python applications/processes
• Commercial experience with Pandas and Polars for data processing, transformation, and analytics
• Experience processing very large datasets (billions of records, terabytes)
• Ability to write efficient and scalable Python code and optimize data processing pipelines
• Experience building/developing/maintaining ETL/ELT processes in Python
• Strong SQL knowledge with practical experience using PostgreSQL
• English proficiency (B2/C1)
• Experience in the financial services industry

Benefits

• Project-based collaboration with stage-based billing and acceptance protocols for deliverables
• Flexible B2B contract for projects delivered for a major financial partner
• Administrative and invoicing/settlement support
• Industry events and technology meetups
• Fast and remote recruitment process
• Referral bonus: 5,000 PLN for recommending friends to projects