Mid Fullstack Developer, React, Java

EX Squared LATAM

Full Stack Developer at EX Squared LATAM designing scalable web applications using React and Java. Contributing to high-impact digital solutions in a collaborative hybrid environment.

Posted 5/7/2026contractSan José • 🇨🇷 Costa RicaMid-LevelSeniorWebsite

Tech Stack

Tools & technologies

AWSCypressJavaJavaScriptJenkinsJestJUnitLinuxMicroservicesMySQLOraclePostgresReactReduxSpringSpring BootSpringBootSQLTypeScriptUnix

About the role

Key responsibilities & impact

Design, develop, and maintain full stack applications using React.js, Java, and Spring Boot
Build scalable and reusable frontend components using modern JavaScript/TypeScript
Develop and optimize backend services and RESTful APIs for enterprise applications
Integrate frontend and backend services with AWS infrastructure (S3, Lambda, API Gateway, RDS)
Work with state management libraries such as Redux, Zustand, Recoil, or Context API
Collaborate with UI/UX designers to create responsive and user-friendly interfaces
Apply object-oriented design principles and design patterns to scalable backend solutions
Optimize application performance across frontend and backend layers
Write unit, integration, and end-to-end tests using frameworks such as Jest, JUnit, Cypress, or Playwright
Participate in CI/CD workflows using GitHub Actions, Jenkins, or GitLab CI
Collaborate with cross-functional teams including Product, QA, Design, and DevOps
Contribute to code reviews, observability, troubleshooting, and continuous improvement initiatives

Requirements

What you’ll need

3+ years of professional experience in Full Stack development
Strong experience with React.js and modern JavaScript/TypeScript (ES6+)
Solid experience with Java, Spring Boot, and Spring MVC
Strong understanding of RESTful APIs and microservices architecture
Experience with relational databases such as PostgreSQL, Oracle, or MySQL
Familiarity with PL/SQL, JSON, and XML
Experience integrating applications with AWS services such as Lambda, API Gateway, S3, and RDS
Experience with frontend state management and React Hooks
Knowledge of HTML5, CSS3, and responsive design principles
Experience with testing frameworks for frontend and backend applications
Familiarity with CI/CD pipelines and Git workflows
Comfortable working in Unix/Linux environments
Strong communication and collaboration skills in agile environments

Benefits

Comp & perks

6-month contract
Hybrid model – Required to attend the office 1 day per week

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills & Tools

React.jsJavaSpring BootJavaScriptTypeScriptRESTful APIsPostgreSQLOracleMySQLCI/CD

Soft Skills

communicationcollaborationagile