Senior Full Stack Software Engineer - Five9

The Team:

We’re seeking talented Full Stack Developer to become part of our diverse, forward- thinking team. You’ll work in a dynamic, global environment where innovation, collaboration, and cutting-edge technology drive real business impact. In this role, you’ll help deliver Five9 global voice features. From initial concept through to delivery, you’ll be involved in every step of the software development lifecycle - translating requirements into technical designs, writing clean and efficient code, and integrating with complex systems.

You’ll join our team that thrives on continuous learning, embraces new technologies, and values smart engineering. Whether deploying cloud-native solutions or integrating secure, scalable APIs, your work will directly shape how organizations operate in the digital age.

If you’re passionate about full-stack development, excited by the opportunity to work on mpactful solutions, and eager to collaborate with like-minded engineers around the world, we’d love to meet you.

*  This position is based out of one of the offices of our affiliate Acqueon Technologies in India, and will adopt the hybrid work arrangements of that location. You will be a member of the Acqueon team with responsibilities supporting Five9 products, collaborating with global teammates based primarily in the United States.

What you’ll be doing:

• Designing and developing both frontend and backend components using modern
  frameworks

• Collaborating with cross-functional teams to deliver robust, maintainable solutions

• Building responsive, user-focused interfaces based on wireframes (e.g., Figma)

• Writing clean, scalable code and implementing state management using tools like
  Redux

• Integrating systems and services using RESTful APIs and secure authentication
  methods (e.g., JWT)

• Participating in agile development processes, including sprint planning and code
  reviews

• Testing, debugging, and optimizing applications across environments

Required Skills & Experience / Qualifications:

• Degree in Computer Science, Technical Science, or similar

• Experience in software development projects across front-end and back-end

• 5 yrs Hands-on experience in:
  ◦ Java, JavaScript, Python, TypeScript
  ◦ React, Redux (State Management), JSX
  ◦ Spring Boot, Spring MVC, Angular, Vue.js

• Proficient in using:
  ◦ Git (GitLab), Jira, Confluence, SVN, Jenkins
  ◦ CSS, Wireframing tools (e.g., Figma)

• Understanding of data structures and clean code principles

• Experience in building and consuming RESTful APIs

• Familiarity with modern authentication mechanisms such as JWT

• Experience with unit, integration, system, and regression testing

• Experience with cloud platforms: Azure, AWS, or GCP

• Strong interest in continuous learning and growing technical skills

• Excellent collaboration, problem-solving, and communication skills

• Fluent in English, both written and spoken

Five9 embraces diversity and is committed to building a team that represents a variety of backgrounds, perspectives, and skills. The more inclusive we are, the better we are. Five9 is an equal opportunity employer. Our headquarters are located in the beautiful Bishop Ranch Business Park in  San Ramon, CA.