Sr. Java Developer at Mavensoft Technologies in Denver, CO
- Company: Mavensoft Technologies
- Location: Denver, CO
- Posted: Sep 23, 2026
- Type: Contract
- Experience: 6+ years
- Visa sponsorship available
Overview
Our Client is seeking an experienced Java Developer Contractor to support the design, development, and maintenance of web applications, backend services, and cloud-based solutions. The ideal candidate will be comfortable working across the Java/Spring ecosystem, building REST APIs, integrating with …
Job description
- Our Client is seeking an experienced Java Developer Contractor to support the design, development, and maintenance of web applications, backend services, and cloud-based solutions.
- The ideal candidate will be comfortable working across the Java/Spring ecosystem, building REST APIs, integrating with AWS services, and contributing to modern CI/CD-driven development workflows. The candidate should be hands-on, pragmatic, able to work independently, and comfortable collaborating with technical and business stakeholders.
Responsibilities
- Design, develop, test, and maintain Java-based applications using Java SDK 21.
- Build and enhance applications using Spring Boot and the Spring Framework.
- Develop and maintain REST APIs and JSON-based integrations.
- Support web applications using Thymeleaf, HTML, CSS, and JavaScript.
- Work with AWS services including ECS, API Gateway, and DynamoDB.
- Contribute to source control and development workflows using GitLab.
- Build, maintain, and troubleshoot GitLab CI/CD pipelines.
- Participate in application architecture, implementation decisions, code reviews, and deployment practices.
- Support infrastructure-as-code efforts, particularly using Terraform.
- Use IntelliJ IDEA as the primary development environment.
- Apply sound software engineering practices including maintainable code, testing, documentation, and operational awareness.
- Leverage AI-assisted coding tools where appropriate to improve productivity and code quality.
Requirements
- Strong professional experience developing applications with Java.
- Experience with Java 21 or recent versions of the Java SDK.
- Solid experience with Spring Boot and Spring-based application development.
- Experience designing, building, and consuming REST APIs.
- Strong working knowledge of JSON and API integration patterns.
- Familiarity with HTML, CSS, and JavaScript.
- Experience with Git-based source control, preferably GitLab.
- Experience with CI/CD pipelines, preferably GitLab CI/CD.
- Practical experience developing, deploying, or supporting applications in AWS.
- Ability to work independently, communicate clearly, and deliver high-quality work in a contractor capacity.
- Experience with Thymeleaf.
- Hands-on experience with Amazon ECS, API Gateway, and DynamoDB.
- Familiarity with Terraform or other infrastructure-as-code tools.
- Professional experience using IntelliJ IDEA.
- 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.
Skills
Required
- Java
- Java 21
- Spring Boot
- Spring Framework
- REST APIs
- JSON
- HTML
- CSS
- JavaScript
- Git
- GitLab
- CI/CD
Preferred
- Thymeleaf
- Amazon ECS
- API Gateway
- DynamoDB
- Terraform
- IntelliJ IDEA
- Cloud deployment troubleshooting
- Secure coding practices