Back End Developer

GemPool Recruitment; Dublin; Remote; EUR 77,000 - 94,000; Full time

Job summary

GemPool Recruitment is seeking an experienced Senior Backend Developer to join a global entertainment technology and data analytics business. The role focuses on building backend services, REST APIs, and data processing pipelines using Java/Jakarta EE in a remote Ireland setting.

You will work with cloud, containers, ETL, and AI-assisted tooling, contributing to platform modernization and scalable architecture.

Qualifications

• 6+ years of Java backend development.
• Experience with Jakarta EE, including JAX-RS, CDI and Servlets.
• Experience with data integration, ETL, batch processing or file ingestion.
• Experience with Redis and PostgreSQL.
• Experience securing REST APIs using JWT or OAuth2.
• AWS experience, especially S3, ECS/EKS, SQS, EventBridge and Secrets Manager.
• Experience migrating on-prem Java apps to cloud.
• Upgrading Java versions (11 to 17/21) and Hibernate (5 to 6).
• Experience with media/entertainment or large-scale datasets.

Responsibilities

• Develop and maintain backend services and REST APIs using Java/Jakarta EE.
• Build and enhance data ingestion processes and ETL pipelines.
• Process and aggregate large volumes of transaction data.
• Write and optimize SQL queries across databases.
• Work with Redis for caching and data access.
• Improve ingestion reliability with validation and monitoring.
• Support backend for new web and mobile apps.
• Contribute to cloud modernization and containerization.
• Develop tests with JUnit and TDD practices.
• Collaborate with Product and Engineering teams on new products.

Skills

Java backend development

REST APIs design

SQL query optimisation

Data integration

Cloud readiness

Tools

Jakarta EE / Java EE servers (TomEE, Payara)

Docker

GitLab CI

Linux environments

Redis

PostgreSQL

SingleStore (MemSQL)

AWS (S3, ECS/EKS, SQS)

OpenAI Codex / Claude Code

Job description

Senior Backend Developer – Java / Data Integration

Location: Remote, Ireland

Experience: 6+ Years

Employment: Permanent, Full-Time

Salary: Up to €85,000

About the Role

GemPool is seeking an experienced Senior Backend Developer to join a global entertainment technology and data analytics business operating within the cinema and film distribution industry.

The company provides data and software solutions that help cinemas, film studios and distributors track box-office performance, manage operations and make informed commercial decisions.

This role will focus on developing new backend products, building and maintaining REST APIs, and improving the systems responsible for collecting, processing and analysing large volumes of cinema transaction data. You will also contribute to ongoing platform modernisation, cloud readiness and the adoption of AI-assisted software development practices.

Key Responsibilities

• Develop and maintain backend services and REST APIs using Java and Jakarta EE.
• Build and enhance data ingestion processes, ETL pipelines and scheduled batch jobs.
• Process, validate and aggregate large volumes of transaction-level data.
• Write and optimise SQL queries across SingleStore and PostgreSQL.
• Work with Redis for caching and data access.
• Improve data ingestion reliability through validation, error handling, monitoring and reprocessing.
• Support backend development for new web and mobile applications.
• Contribute to cloud modernisation and containerisation initiatives.
• Develop automated tests using JUnit and follow test-first development practices.
• Collaborate with Product and Engineering teams on new product development.
• Participate in code reviews and maintain clean, scalable and reliable application architecture.
• Use AI coding tools to support development workflows while maintaining ownership of code quality and delivery.

Requirements

• 6+ years' professional experience in Java backend development.
• Strong experience with Java EE / Jakarta EE, including JAX-RS, CDI and Servlets.
• Experience working with TomEE, Payara or similar Java application servers.
• Strong SQL and JDBC skills, including query optimisation and transaction management.
• Hands-on experience with data integration, ETL, batch processing or file ingestion.
• Experience with Redis and relational databases such as PostgreSQL.
• Experience developing and securing REST APIs using JWT or OAuth2.
• Understanding of API versioning and maintaining backward compatibility.
• Experience with JUnit, automated testing and test-first development.
• Comfortable working with Docker, GitLab CI and Linux environments.
• Practical experience using Claude Code or OpenAI Codex for AI-assisted and agent-driven software development.
• Strong problem-solving skills and the ability to work collaboratively within an engineering team.
• Experience with SingleStore (MemSQL), distributed SQL or columnar databases.
• AWS experience, particularly S3, ECS/EKS, SQS, EventBridge and Secrets Manager.
• Experience migrating on-premise Java applications to cloud environments.
• Experience upgrading Java versions (11 to 17/21) and Hibernate (5 to 6).
• Experience working with media, entertainment, financial or other large-scale transaction datasets.