Senior Backend Developer (Java or Python)

Quick Facts

• Rate: up to 130 PLN/h net + VAT

• Work model: Hybrid (3 days/week from the office)

• Location: Warsaw, Gdańsk, or Gdynia

• Contract type: B2B agreement

Description

You will contribute to the Automated Security Retest Engine—an automated security retesting platform that analyzes security assessment reports and verifies remediation actions. The project includes a Python-based processing pipeline and a Java Spring Boot web application that provides the user interface.

Responsibilities

• Design and implement new platform features

• Integrate external tools and APIs

• Improve reliability and quality of generated tests and analysis

• Write automated tests, investigate defects, and maintain technical documentation

• Collaborate with security and product stakeholders to translate requirements into maintainable software

• Ensure security as a core requirement: preserve target-scope restrictions, protect credentials and user data, validate inputs, and provide reliable evidence for retest outcomes

Requirements

• Professional software development experience in Python and/or Java

• Experience developing and maintaining backend applications and REST APIs

• Java: familiarity with Spring Boot and common application-development practices

• Python: familiarity with modular application design, dependency management, and automated testing

• Proven experience writing and maintaining automated tests

• Working knowledge of Git and collaborative workflows (including code reviews)

• Understanding of secure software development (input validation, authentication, authorization, safe handling of secrets)

• Ability to analyze an existing codebase, troubleshoot issues, and deliver changes with appropriate documentation

• Good written and spoken English for technical communication

Benefits

• B2B agreement with Optiveum as the contracting party

• Transparent working conditions

• Ongoing support from the Optiveum team throughout the cooperation

• Opportunity to work in an international, highly collaborative environment