Java backend developer for checkout systems

Ytech; Lisboa; On-site; EUR 55,000 - 85,000; Full time

Benefits offered by this job

Training & certification

Professional growth

International project exposure

Job summary

Ytech, based in Lisboa, Portugal, seeks a Java Backend Developer with 4+ years of experience to join an international project delivering digital solutions in Checkout, MyAccount and ODR processing.

You will design, build and maintain scalable microservices, REST and GraphQL APIs, and contribute to architecture decisions. The role involves IAM integrations, cloud components, and collaboration with frontend teams to deliver high-quality software.

Qualifications

• More than 4 years of professional software development experience.
• Strong Java backend development experience.
• Experience with microservices architectures.
• Experience building REST APIs.
• Knowledge of GraphQL and OpenAPI/Swagger.
• Experience with authentication and authorization (OIDC, RBAC).
• Knowledge of Keycloak, Okta, RBAC and token management.
• Experience with messaging systems and asynchronous processing (AWS SQS).
• Experience with unit/integration testing and code reviews.
• Knowledge of SonarQube and Snyk for code quality and security.
• Collaborate with frontend teams (React).
• Ability to participate in architecture decisions and mentor juniors.
• Portuguese and English at C1 level.

Responsibilities

• Design, develop and maintain scalable Java microservices.
• Define architecture and drive technical decisions for solutions.
• Own feature lifecycle from design to deployment.
• Develop and maintain REST and GraphQL APIs.
• Create and maintain OpenAPI/Swagger documentation.
• Integrate IAM with Keycloak/Okta and manage tokens (OIDC/RBAC).
• Implement asynchronous processing with AWS SQS/Solace.
• Ensure code quality and security via SonarQube and Snyk.
• Identify and resolve performance and security issues.
• Support and guide junior developers.
• Collaborate with frontend teams (React) on integrated solutions.
• Contribute to engineering standards and knowledge sharing.

Skills

Java

Backend development

Microservices

REST APIs

GraphQL

OpenAPI/Swagger

IAM (Keycloak/Okta/OIDC/RBAC)

AWS SQS/Solace

Unit testing

Code reviews

Mentoring juniors

React collaboration

Portuguese & English C1

Tools

Swagger

SonarQube

Snyk

AWS

Job description

Описание:

At Ytech, we live and breathe technology. Our mission is to transform challenges into solutions and find new ways to innovate every day. Founded in 2020, we are a technology start-up operating in the IT and Telecommunications sectors, with a clear ambition: to shake up the market, break patterns and create real value through innovation. We are looking for a Java Backend Developer with more than 4 years of experience to join an international project focused on developing digital solutions in Checkout, MyAccount and ODR processing.

Задачи:

• Design, develop and maintain scalable microservices in Java;
• Participate in defining the architecture and making technical decisions about the solutions;
• Take ownership of the complete feature lifecycle: design, implementation, testing, code review and deployment;
• Develop and maintain REST and GraphQL APIs;
• Create and update technical documentation using OpenAPI/Swagger;
• Integrate and configure Identity and Access Management (IAM) solutions with Keycloak and Okta;
• Implement authentication and authorization flows with OIDC, RBAC and token customization;
• Develop asynchronous integrations and event-driven architectures with AWS SQS and Solace;
• Ensure code quality and security through SonarQube, Snyk and code reviews;
• Identify and resolve technical issues related to performance, scalability and security;
• Support and guide junior developers;
• Promote knowledge sharing within the team;
• Contribute to defining and evolving the client's engineering standards;
• Collaborate with frontend teams, particularly on solutions developed in React.

Требования:

• More than 4 years of professional experience in software development;
• Strong experience in Java and backend development;
• Experience developing microservices-based architectures;
• Experience developing and integrating REST APIs;
• Knowledge of GraphQL and OpenAPI/Swagger;
• Experience with authentication and authorization systems;
• Knowledge of Keycloak, Okta, OIDC, RBAC and token management;
• Experience with messaging systems and asynchronous processing;
• Knowledge of AWS SQS and/or Solace;
• Experience with unit testing, integration testing and code reviews;
• Knowledge of quality and security tools such as SonarQube and Snyk;
• Knowledge of React and the ability to collaborate with frontend teams;
• Ability to participate in architecture decisions;
• Experience supporting or mentoring junior developers;
• Ability to work autonomously and take on technical responsibilities;
• Portuguese and English at C1 level;

Условия:

• A technologically challenging project with a direct impact on digital solutions for Checkout, MyAccount and ODR processing;
• Training and certification program;
• Ongoing support from the Ytech team;
• A collaborative environment focused on professional growth;
• The opportunity to participate in technical and architectural decisions;
• Joining a team that values autonomy, innovation and knowledge sharing;
• Exposure to modern architectures, microservices and cloud technologies.