Senior Backend Developer (Python)

TL;DR

Senior Backend Developer (Python): Building and optimizing high-load backend services and data pipelines for a platform with an accent on REST APIs, database performance, and scalability. Focus on integrating scenario creation workflows, diagnosing system defects, and applying TDD within an agile environment.

Location: 100% remote

Salary: 1200–1400 PLN net/day

What you will do

• Integrate scenario creation and sampling workflows and develop REST APIs in Python.
• Build and maintain data pipelines, enabling data consumption across the platform.
• Diagnose and resolve API and system defects, driving performance improvements.
• Apply TDD, perform unit tests, and run dockerized integration testing.
• Deploy, monitor, and maintain project infrastructure and services.
• Collaborate actively in an agile environment through stand-ups, reviews, and code reviews.

Requirements

• Excellent hands-on experience with Python (3.14), Flask, or FastAPI.
• Strong knowledge of SQL and NoSQL databases, including practical experience with Pandas/Dask/Spark for data wrangling.
• Practical experience with AWS services (EC2, ECS/Fargate, ECR, Lambda, S3, Cognito, DynamoDB, Aurora, CloudWatch, Secrets Manager, SQS).
• Solid background in application and infrastructure design, with experience in TDD, unit, and dockerized integration testing.
• Minimum 5+ years of professional software development.
• Required language proficiency: English — B2, Polish — C1.

Nice to have

• General understanding of probability.
• Experience deploying infrastructure with Terraform.
• Experience working with RDBMS.
• Familiarity with MCP technologies.
• BS/MS in Computer Science or Engineering.

Culture & Benefits

• Opportunity to freely pinpoint areas for improvement and communicate vision for growth.
• Open sharing of suggestions, observations, and knowledge.
• Daily examples, shared experiences, and mutual help.
• Work model: 100% remote.
• Core hours: 7:00–9:00 + 8h.