# Full Stack Engineer
**Company:** [Phonely](https://hotfix.jobs/companies/phonely)
**Location:** San Francisco, CA
**Experience:** 5+ years
**Skills:** React, Next.js, TypeScript, Python, Kubernetes, AWS, GCP, Redis, Firebase, Supabase, Datadog, CI/CD
**Posted:** 2026-04-13
> Builds and maintains full-stack web applications with React/Next.js, integrates backend APIs and voice AI systems, optimizes performance, and owns UI/UX. Requires 5+ years experience, strong full-stack skills, and TypeScript proficiency in a fast-paced onsite environment.
## Job Description
## Responsibilities
- Build and maintain high-performance, responsive web applications using React and Next.js
- Design and implement end-to-end features across frontend and backend systems
- Work closely with backend engineers to integrate APIs, real-time systems, and voice AI workflows
- Own UI/UX quality—craft fast, intuitive, and reliable user experiences
- Manage state effectively across complex applications (server + client state)
- Optimize frontend performance (latency, rendering, caching, edge delivery)
- Build internal tools and dashboards for monitoring, debugging, and controlling AI agents
- Write clean, maintainable, and well-tested code across the stack
- Debug production issues and continuously improve reliability and usability
- Contribute to system design, architecture decisions, and product direction

## Qualifications
- 5+ years of experience building production applications
- Strong experience with React and Next.js
- Experience building full-stack applications (API design, backend integration)
- Solid understanding of TypeScript, modern frontend tooling, and state management
- Experience working with APIs, real-time systems, and async data flows
- Understanding of performance optimization and scalable frontend architecture
- Familiarity with cloud environments, CI/CD, and modern deployment workflows
- Strong product sense and attention to detail
- Clear communicator who can work across teams

## Software Stack
**Frontend:** React, Next.js, TypeScript
**Backend:** Python, microservices, async systems
**Cloud & Infra:** AWS, GCP, Kubernetes, Redis
**Databases:** Firebase, Supabase
**Observability:** Datadog, logging, metrics, tracing
**Voice AI:** SIP, real-time call handling, LLM orchestration
**Other:** CI/CD, testing, resilient architecture
**Apply:** https://hotfix.jobs/jobs/full-stack-engineer-at-phonely-fd484e5a-b31f-4882-b3db-37492f79f2b2
**Canonical:** https://hotfix.jobs/jobs/full-stack-engineer-at-phonely-fd484e5a-b31f-4882-b3db-37492f79f2b2