What are the responsibilities and job description for the Fullstack Software Engineer position at Apex Systems?
Job#: 3029614
Job Description:
Senior Software Engineer I – Full Stack (AI)
Location: Denver, CO (Onsite 4 days/week)
We are looking for a Senior Software Engineer I (Full Stack). This role is heavily focused on backend systems and data-driven reporting, with meaningful responsibility for building the foundation that powers client-facing insights and internal decision-making.
You’ll work across the stack, primarily backend, building scalable services, APIs, and data integrations that support advanced reporting, AI-enabled dashboards, and agent-driven user experiences. This role offers strong ownership, real business impact, and exposure to emerging AI technologies.
What You’ll Do
Apex Benefits Overview: 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. 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, 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. 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 Apex team member can provide.
Apex Systems is a world-class IT services company that serves thousands of clients across the globe. When you join 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 ClearlyRated's Best of Staffing® in Talent Satisfaction in the United States and Great Place to Work® in the United Kingdom and Mexico. Apex uses a virtual recruiter as part of the application process. Click here for more details.
Apex Benefits Overview: 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. 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, 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. 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 Apex team member can provide.
Apex Systems is part of the Commercial Segment of ASGN Incorporated.
NYSE: ASGN
4400 Cox Road
Suite 200
Glen Allen, Virginia 23060
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. Apex will consider qualified applicants with criminal histories in a manner consistent with the requirements of applicable law. If you have visited our website in search of information on employment opportunities or to apply for a position, and you require an accommodation in using our website for a search or application, please contact our Benefits Department at [email protected] or 804-523-8228. (Do not submit resumes or solicit consultants to this email address). UnitedHealthcare creates and publishes the Transparency in Coverage Machine-Readable Files on behalf of Apex Systems.
Job Description:
Senior Software Engineer I – Full Stack (AI)
Location: Denver, CO (Onsite 4 days/week)
We are looking for a Senior Software Engineer I (Full Stack). This role is heavily focused on backend systems and data-driven reporting, with meaningful responsibility for building the foundation that powers client-facing insights and internal decision-making.
You’ll work across the stack, primarily backend, building scalable services, APIs, and data integrations that support advanced reporting, AI-enabled dashboards, and agent-driven user experiences. This role offers strong ownership, real business impact, and exposure to emerging AI technologies.
What You’ll Do
- Design, build, deploy, and maintain scalable full-stack applications, with a primary emphasis on backend development
- Develop and maintain backend services, RESTful APIs, and microservices that power reporting, analytics, and AI-driven experiences
- Build and enhance client-facing dashboards and reporting tools that help visualize campaign performance and identify execution gaps
- Integrate and manage multiple data sources, ensuring data integrity, performance, and reliability
- Collaborate closely with Data Science, Operations, and Engineering partners to deliver end-to-end solutions
- Optimize system performance by identifying and resolving bottlenecks across services, databases, and APIs
- Write clean, maintainable, and well-tested code (unit, integration, and end-to-end tests)
- Conduct code reviews and contribute to architectural and design discussions
- Mentor junior engineers and help foster a culture of quality and ownership
- Coordinate with contractors or consultants when applicable and own delivered outcomes
- Backend-first full-stack role (approximately 70% backend / 30% frontend)
- Backend development supporting:
- AI-enabled dashboards
- Agentic and chat-based user experiences
- Data-heavy reporting and analytics workflows
- 3 years of professional full-stack software development experience
- Strong experience with Node.js, TypeScript, and modern frontend frameworks such as React, Angular, or Vue
- Solid backend and data experience, including RESTful APIs, microservices, relational and NoSQL databases (MySQL, MongoDB, Redis), and database performance optimization
- Strong problem-solving skills and attention to detail
- Experience writing and maintaining automated tests
- Excellent communication and collaboration skills
- Experience in AdTech, analytics, or data-heavy platforms
- Familiarity with AI / GenAI concepts, including dashboards, agents, or chat experiences
- Ability to build AI agents or services from scratch (strong plus)
- Experience with Python or Go (Golang)
- CI/CD pipelines and production deployment experience
- Containerization and orchestration using Docker and Kubernetes
- Exposure to Databricks, Tableau, or modern data platforms
- Real business impact on how clients and internal teams make decisions
- Opportunity to deepen backend expertise while expanding into AI and data platforms
- Strong collaboration with data science and product-aligned teams
- Clear growth path through technical leadership and system ownership
Apex Benefits Overview: 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. 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, 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. 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 Apex team member can provide.
Apex Systems is a world-class IT services company that serves thousands of clients across the globe. When you join 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 ClearlyRated's Best of Staffing® in Talent Satisfaction in the United States and Great Place to Work® in the United Kingdom and Mexico. Apex uses a virtual recruiter as part of the application process. Click here for more details.
Apex Benefits Overview: 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. 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, 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. 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 Apex team member can provide.
Apex Systems is part of the Commercial Segment of ASGN Incorporated.
NYSE: ASGN
4400 Cox Road
Suite 200
Glen Allen, Virginia 23060
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. Apex will consider qualified applicants with criminal histories in a manner consistent with the requirements of applicable law. If you have visited our website in search of information on employment opportunities or to apply for a position, and you require an accommodation in using our website for a search or application, please contact our Benefits Department at [email protected] or 804-523-8228. (Do not submit resumes or solicit consultants to this email address). UnitedHealthcare creates and publishes the Transparency in Coverage Machine-Readable Files on behalf of Apex Systems.
Salary : $135,000 - $162,000