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Sr Software Engineer

Apex Systems Inc

Senior Software Engineer (Contract)

Location: St. Louis, MO preferred (hybrid, 4 days onsite). Remote candidates may be considered based on experience.

Duration: 12-18 months with potential extension

Overview

We are seeking a Senior Software Engineer to join a team responsible for enhancing and modernizing large-scale financial and transaction processing applications. This is a hands-on engineering role within an Agile environment where developers are expected to contribute across application design, development, modernization, automation, and production support initiatives.

The ideal candidate enjoys solving complex technical challenges, reducing technical debt, and building scalable cloud-native solutions using modern engineering practices.

What You'll Do
  • Design, develop, and maintain microservices using Java, Spring Boot, and TypeScript.
  • Build and enhance cloud-native applications deployed within AWS environments.
  • Contribute to both modernization efforts and new feature development.
  • Partner with architects and Agile teams to translate business and technical requirements into scalable solutions.
  • Participate in code reviews, architecture discussions, and engineering best practices initiatives.
  • Improve application quality through automated testing, CI/CD, and ongoing refactoring efforts.
  • Troubleshoot production issues, optimize performance, and support critical business applications.
  • Help drive adoption of emerging technologies and AI-assisted development tools.
Required Experience
  • 5+ years of recent software engineering experience in hands-on development roles.
  • Strong experience with Java and Spring Boot.
  • Experience building and supporting microservices-based applications.
  • Exposure to AWS services such as EKS, ECS, Lambda, RDS, or similar cloud technologies.
  • Front-end development experience with Angular and TypeScript.
  • Strong problem-solving, communication, and technical documentation skills.
  • Experience working within Agile delivery teams.
Preferred Experience
  • Cloud modernization and legacy application transformation initiatives.
  • Infrastructure-as-Code tools such as CloudFormation or CDK.
  • Test automation frameworks and behavior-driven development practices.
  • CI/CD pipeline implementation and support, including GitLab.
  • Experience working in highly regulated or security-focused environments.
  • Familiarity with observability and monitoring tools.
  • Experience reducing technical debt through upgrades, refactoring, and automation.
Tech Stack

Java • Spring Boot • TypeScript • Angular • AWS (EKS, ECS, Lambda, RDS) • Microservices • REST APIs • GitLab CI/CD • Test Automation • Cloud-Native Architecture

Everforth Apex is a world-class IT services company that serves thousands of clients across the globe. When you join Everforth Apex, you become part of a team that values innovation, collaboration, and continuous learning. We offer quality career resources, training, certifications, development opportunities, and a comprehensive benefits package. Our commitment to excellence is reflected in many awards, including ClearlyRateds Best of Staffing® in Talent Satisfaction in the United States and Great Place to Work® in the United Kingdom and Mexico.

Everforth Apex uses a virtual recruiter as part of the application process. Click here for more details. By applying for this job, you agree to receive calls, AI-generated calls, text messages, or emails from Everforth Apex and its affiliates, and contracted partners. Frequency varies for text messages. Message and data rates may apply. Carriers are not liable for delayed or undelivered messages. You can reply STOP to cancel and HELP for help. You can access our privacy policy at

Everforth Apex Benefits Overview: Everforth Apex offers a range of supplemental benefits, including medical, dental, vision, life, disability, and other insurance plans that offer an optional layer of financial protection. We offer an ESPP (employee stock purchase program) and a 401K program which allows you to contribute typically within 30 days of starting, with a company match after 12 months of tenure. Everforth Apex also offers a HSA (Health Savings Account on the HDHP plan), a SupportLinc Employee Assistance Program (EAP) with up to 8 free counseling sessions, a corporate discount savings program and other discounts. In terms of professional development, Everforth Apex hosts an on-demand training program, provides access to certification prep and a library of technical and leadership courses/books/seminars once you have 6+ months of tenure, and certification discounts and other perks to associations that include CompTIA and IIBA. Everforth Apex has a dedicated customer service team for our Consultants that can address questions around benefits and other resources, as well as a certified Career Coach. You can access a full list of our benefits, programs, support teams and resources within our 'Welcome Packet' as well, which an Everforth Apex team member can provide.

Everforth Apex Systems is an equal opportunity employer. We do not discriminate or allow discrimination on the basis of race, color, religion, creed, sex (including pregnancy, childbirth, breastfeeding, or related medical conditions), age, sexual orientation, gender identity, national origin, ancestry, citizenship, genetic information, registered domestic partner status, marital status, disability, status as a crime victim, protected veteran status, political affiliation, union membership, or any other characteristic protected by law. Everforth Apex will consider qualified applicants with criminal histories in a manner consistent with the requirements of applicable law.

If you require an accommodation under the Americans with Disabilities Act to participate in an interview with a virtual recruiter or to use our website for a search or application, please contact our Benefits Department at [email protected] or View phone number on click.appcast.io. Please note that this contact information is strictly to be used for medical ADA accommodations and that no other inquiries will be answered.

UnitedHealthcare creates and publishes the Transparency in Coverage Machine-Readable Files on behalf of Everforth Apex Systems.
Vacancy posted 2 days ago
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