Java Backend Engineer: AI‑Powered Microservices (Remote)

Sigli; Poland; On-site; PLN 179,000 - 298,000; Full time

Benefits offered by this job

Mentorship Program

Remote flexibility

Structured growth

Job summary

Sigli is seeking an experienced backend engineer to join our international team on a 9-month remote project. You will design, develop, and maintain scalable Java microservices and REST APIs powering dashboards, reporting, and data integration for enterprise customers.

The role emphasizes PostgreSQL data handling, AI-assisted development, and collaboration with Product, QA, DevOps, and other engineering teams across Europe. Strong English communication is essential.

Qualifications

• 4+ years of professional Java development experience, with a strong background in microservices.
• Strong knowledge of Spring Boot and the wider Spring ecosystem.
• Experience designing and developing REST APIs.
• Experience with PostgreSQL or another relational database.
• Experience building backend services that provide data to dashboards, reporting systems, or analytical applications.
• Experience with TestContainers, Maven or Gradle, and Docker Compose.
• Strong experience designing technical solutions and communicating architectural decisions.
• Proficiency in AI-assisted development using Claude Code or similar tools.
• Strong communication and collaboration skills.
• English at Upper-Intermediate level or higher.

Responsibilities

• Design, develop, and maintain scalable microservices using Java and the Spring Boot ecosystem.
• Build and maintain REST APIs for internal and external consumers, including dashboards, reporting, and bulk data access.
• Ensure processed data is reliably exposed to frontend dashboards and reporting APIs.
• Integrate with third-party data sources, particularly Microsoft Graph APIs and Microsoft Partner Center APIs.
• Use AI-assisted development tools such as Claude Code to accelerate delivery without compromising code quality.
• Write and maintain integration tests using TestContainers.
• Manage builds with Maven or Gradle and local environments with Docker Compose.
• Contribute to architectural decisions and clearly explain and defend technical solutions.
• Collaborate closely with Product, QA, DevOps, and other engineering teams.
• Develop backend solutions for large-scale data collection, ingestion, storage, processing, and transformation.
• Design and optimize PostgreSQL data structures for large datasets, BI reporting, analytical use cases, and bulk import/export processes.
• Contribute to data pipeline and data processing design, including data quality, scalability, and performance considerations.
• Integrate AI systems or agents with reporting data, vector databases, semantic caching, or similar technologies where relevant.

Skills

Java

Spring Boot

REST APIs

PostgreSQL

TestContainers

Maven/Gradle

Docker Compose

AI-assisted development

Communication

English

Tools

TestContainers

Docker Compose

Maven/Gradle

Job description

Sigli is seeking an experienced backend engineer to join our international team on a 9-month remote project. You will design, develop, and maintain scalable Java microservices and REST APIs powering dashboards, reporting, and data integration for enterprise customers.

The role emphasizes PostgreSQL data handling, AI-assisted development, and collaboration with Product, QA, DevOps, and other engineering teams across Europe. Strong English communication is essential.