Senior Backend Developer

Bydgoszcz; Poznań; On-site; PLN 120,000 - 180,000; Full time

Job summary

A leading company is seeking a skilled backend developer to enhance their Django and GraphQL API. The candidate will build essential services, shape AWS infrastructure, and ensure application performance. Ideal applicants have strong Python and SQL skills with a commitment to quality through testing and code reviews.

Qualifications

• 5 years of experience in software development.
• Production experience with Python and Django required.
• Strong SQL skills and performance tuning.

Responsibilities

• Own and extend the Django 4 + GraphQL API.
• Build scoring logic, XP/level engine, and leaderboard service.
• Participate in code reviews and maintain performance.

Skills

Python

Django

SQL

REST

GraphQL

Docker

CI/CD

AWS

GitHub Actions

Job description

Own and extend our Django 4 + GraphQL API (Python 3.12).

Build the hand-parser, scoring logic, XP/level engine, and leaderboard service.

Add notification pipelines (in-app, email, push via AWS SNS).

Customize Django Admin for content import and user moderation.

Help shape our AWS infrastructure (ECS Fargate, RDS PostgreSQL, S3) using Terraform and GitHub Actions CI/CD.

Write robust tests with pytest, maintain p95 responses < 200 ms, and participate in rigorous code reviews.

Our requirements

• 5 years of experience
• Production experience with Python/Django
• Strong SQL skills and performance tuning
• Proven REST/GraphQL API design and test automation
• Comfortable with Docker and CI/CD workflows

Optional

• Gamification or ed-tech background, AWS CDK, basic TypeScript familiarity