Senior Java Developer

Nix; España; Teletrabalho; EUR 70 000 - 110 000; Tempo integral

Vantagens oferecidas por esta oferta de emprego

Flexible working format (remote/office

Competitive salary

Career growth

Professional development tools

Education reimbursement

Tech communities & trainings

Corporate events

Location-specific benefits

Resumo da oferta

N-iX is seeking a Senior Java Developer to join a long-term modernization effort for a large US-based provider, focusing on upgrading a legacy Java platform while preserving essential business functions. You will work in the European supply chain context, modernizing the stack and addressing security to support the next 5–7 years.

The role emphasizes a cost-effective modernization without a full rewrite, with collaboration across technical stakeholders and a transition from javax to jakarta as

Qualificações

• 5+ years of commercial Java experience.
• Proven experience with Struts 1.x.
• Experience with Java version upgrades and/or framework migrations.
• Strong knowledge of Apache Tomcat and Linux environments.
• Experience with SQL Server and Oracle databases.
• Solid understanding of JDBC and stored procedures.
• Experience testing and maintaining legacy applications.
• Fluent English (spoken and written).
• Based in the EU.

Responsabilidades

• Lead and execute the migration of a large legacy Java application.
• Upgrade Java versions and modernize the framework stack.
• Migrate from javax to jakarta.
• Upgrade dependencies and address security vulnerabilities.
• Refactor legacy code where required.
• Create unit and integration tests for existing functionality.
• Support regression testing activities.
• Collaborate with the customer’s technical stakeholders.
• Deliver early security improvements and test coverage for critical business flows.

Conhecimentos

Java expertise

Struts 1.x experience

Linux knowledge

Tomcat knowledge

Problem solving

English fluency

Ferramentas

Struts 1.x

Apache Tomcat

Azure DevOps

Ant

XSLT/XML transformations

Descrição da oferta de emprego

N-iX is looking for a Senior Java Developer to join a long-term modernization initiative for a large US-based provider of marketing, packaging, print, and supply chain services serving Fortune-level clients worldwide.

You will work within the customer's European supply chain division, supporting warehousing, fulfillment, kitting, and packaging operations for global brands in electronics, medical devices, and consumer products. The main stakeholder is a Software Development Manager who originally built the system and remains deeply involved in its technical evolution.

About the Project

The project focuses on a customer-facing web portal that has been operating successfully for over two decades. The portal enables customers, suppliers, and partners to:

• View inventory, goods, and shipment reports
• Exchange files securely
• Submit forecasts and operational data
• Access supply chain information

The system has been in maintenance mode for several years and now requires a strategic technology uplift to address security vulnerabilities and ensure continued support for the next 5–7 years. This is not a rewrite project. The goal is a cost-effective modernization of the existing platform while preserving business-critical functionality.

Technology Stack

• Java 8
• Struts 1.1
• STXX (XML/XSLT)
• Apache Tomcat 9
• Apache HTTP Server
• Linux
• Ant
• Azure DevOps

Data & Integrations:

• Microsoft SQL Server
• Oracle Database
• Stored Procedures
• LDAP
• SFTP
• Email integrations

Application Size:

• 200,000+ lines of Java code
• Monolithic architecture
• No automated test coverage currently in place

Responsibilities

• Lead and execute the migration of a large legacy Java application
• Upgrade Java versions and modernize the framework stack
• Perform migration from javax to jakarta
• Upgrade dependencies and address security vulnerabilities
• Analyze and refactor legacy code where required
• Create unit and integration tests for existing functionality
• Support regression testing activities
• Collaborate closely with the customer’s technical stakeholders
• Deliver early security improvements and test coverage for critical business flows during the initial project phase

Requirements

Must Have

• 5+ years of commercial experience with Java
• Proven experience working with Struts 1.x
• Experience with Java version upgrades and/or framework migration projects
• Strong knowledge of Apache Tomcat and Linux environments
• Experience working with SQL Server and Oracle databases
• Solid understanding of JDBC and stored procedures
• Experience testing and maintaining legacy applications
• Strong problem-solving and debugging skills
• Fluent spoken and written English
• Based in the EU

Nice to Have

• Experience with AI-assisted migration tools (OpenRewrite, GitHub Copilot, Claude, Gemini, etc.)
• Knowledge of XSLT/XML transformations
• Experience migrating build systems from Ant to Maven or Gradle
• Experience with Azure DevOps
• Experience with large monolithic enterprise applications

We offer*:

• Flexible working format - remote, office-based or flexible
• A competitive salary and good compensation package
• Personalized career growth
• Professional development tools (mentorship program, tech talks and trainings, centers of excellence, and more)
• Active tech communities with regular knowledge sharing
• Education reimbursement
• Memorable anniversary presents
• Corporate events and team buildings
• Other location-specific benefits

*not applicable for freelancers