Senior Java Developer

Apex Systems; Denver (CO); Hybrid; USD 120,000 - 160,000; Full time

Job summary

Apex Systems seeks a Senior Java Developer to design, develop, test, and maintain Java applications using Java SDK 21. You will build and enhance applications with Spring Boot, develop REST APIs, and support Thymeleaf templates.

You’ll work with AWS services, manage GitLab CI/CD pipelines, and contribute to Terraform-based infrastructure as code. Collaboration on architecture and deployment practices is essential.

Qualifications

• Strong Java development experience.
• Experience with Spring Framework and Spring Boot.
• Hands-on AWS deployment and Terraform IaC.
• Ability to write unit and integration tests and documentation.

Responsibilities

• Design, develop, test, and maintain Java applications.
• Build REST APIs and server-side templates with Thymeleaf.
• Collaborate on architecture, decisions, and code reviews.
• Maintain GitLab CI/CD pipelines and IaC deployments.

Skills

Java

Spring Boot

REST APIs

AWS

AI-assisted coding

Thymeleaf

IntelliJ IDEA

GitLab CI/CD

Security best practices

Tools

IntelliJ IDEA

GitLab

Terraform

AWS

Job description

## Job Description# Senior Java Developer* Design, develop, test, and maintain Java-based applications using Java SDK 21.* Build and enhance applications using Spring Boot and the broader Spring Framework.* Develop and maintain REST APIs and JSON-based integrations.* Support smaller web applications using Thymeleaf, HTML, CSS, and JavaScript.* Work with AWS-based infrastructure and services, including ECS, API Gateway, and DynamoDB.* Contribute to source control and development workflows using GitLab.* Build, maintain, and troubleshoot GitLab CI/CD pipelines.* Collaborate with team members on application architecture, implementation decisions, code reviews, and deployment practices.* Support infrastructure-as-code efforts, especially where Terraform is used.* Use IntelliJ IDEA as the primary development environment.* Apply sound software engineering practices, including maintainable code design, testing, documentation, and operational awareness.* Where appropriate, leverage AI-assisted coding tools to improve development productivity and code quality.* Experience with Thymeleaf for server-side templating.* Hands-on experience with AWS services such as:+ Amazon ECS+ Amazon API Gateway+ Amazon DynamoDB* Familiarity with Terraform or other infrastructure-as-code tools.* Experience using IntelliJ IDEA in a professional development environment.* Familiarity with AI-assisted development tools such as Claude Code, GitHub Copilot, Cursor, or similar tools.* Experience troubleshooting cloud deployments, application logs, build pipelines, and environment-related issues.* Understanding of secure coding practices and cloud application security concepts.