Senior Java Software Engineer

SOLID.Jobs; Kraków; On-site; PLN 180,000 - 240,000; Full time

Job summary

SOLID.Jobs in Kraków is seeking a Senior Java Developer to join our high-performance team building modern, large-scale backend systems for travel and transportation.

You will lead backend design, implementation, and API optimization for mission-critical platforms used by millions of travelers worldwide.

As a Senior Developer, you will mentor engineers, shape system architecture, and ensure performance and reliability while collaborating with product and SRE teams to evolve CI/CD processes.

Qualifications

• 7–9 years of backend software development experience.
• Strong proficiency in Java and Java EE technologies.
• Deep knowledge of Spring, Hibernate, and RESTful web services.
• Solid grasp of OOP principles and design patterns.
• Experience working with XML and relational databases (Oracle, SQL).
• Familiarity with Linux-based development environments.
• Experience with build tools like Ant, Maven, or Gradle.
• Hands-on experience with Apache Camel and ServiceMix.
• Strong communication and team leadership skills.

Responsibilities

• Design, implement, and optimize backend services and APIs.
• Lead a team to design and implement backend solutions.
• Mentor developers and promote engineering excellence.
• Collaborate with Product to understand business requirements.

Skills

Java

Spring

Hibernate

RESTful web services

OOP principles

Linux-based development

Build tools

Apache Camel

ServiceMix

Team leadership

Tools

Ant

Maven

Gradle

XML

Oracle

SQL

JBoss

JMX

Drools

JMS

Job description

We are looking for a Senior Java Developer with 7+ years of experience to join our high-performing team developing modern, large-scale backend systems for the travel and transportation industry.

If you have a strong background in Java development, cloud-native architecture, and enterprise-grade application design, this is your opportunity to take part in building the technology behind global travel experiences.

As a Senior Java Developer, you will lead a team to design, implement, and optimize backend services and APIs that power mission-critical systems used by millions of travelers worldwide. You’ll play a key role in shaping system architecture, ensuring performance, reliability, and scalability — while mentoring developers and contributing to a culture of engineering excellence.

YOUR ROLE

• Design, develop, test, and debug complex software solutions
• Design and build prototype applications
• Research best practices, new tools, and technology.
• Work closely with technical staff to understand problems with software and resolve them
• Work closely with the Product team to understand business requirements
• Assist in the development of software technical documentation
• Support SRE in our effort to evolve CI/CD processes and stability

MUST HAVE

• 7–9 years of experience in backend software development.
• Strong proficiency in Java and related Java EE technologies.
• Deep knowledge of Spring, Hibernate, and RESTful web services.
• Solid grasp of OOP principles and design patterns.
• Experience working with XML and relational databases (Oracle, SQL).
• Familiarity with Linux-based development environments.
• Experience with build tools like Ant, Maven, or Gradle.
• Hands-on experience with Apache Camel and/or ServiceMix.
• Strong communication and team leadership skills.

NICE TO HAVE

• Experience working in Agile/Scrum development teams.
• Knowledge of JMS, JBoss, JMX, Drools.
• Understanding of TDD and experience with JUnit/unit testing.
• Java
• Spring
• Hibernate
• RESTful
• XML
• Apache
• Polski
• Angielski