---
title: 'Senior Software Engineer - Frontend at Five9'
canonical: 'https://feeny.ai/job/senior-software-engineer-frontend-five9-porto-m3qgm1m68m83'
type: 'job'
last_seen: '2026-09-24'
---

# Senior Software Engineer - Frontend at Five9

- **Company:** Five9
- **Location:** Porto, Portugal
- **Work type:** hybrid
- **Posted:** 2026-09-18
- **Last confirmed live:** 2026-09-24
- **Apply:** https://www.five9.com/about/careers/job-detail?gh_jid=6200258004

## Job description

Join us in bringing joy to customer experience.  Five9 is a leading provider of cloud contact center software, bringing the power of cloud innovation to customers worldwide.

Living our values everyday results in our team-first culture and enables us to innovate, grow, and thrive while enjoying the journey together. We celebrate diversity and foster an inclusive environment, empowering our employees to be their authentic selves.

Five9 has led the cloud revolution in contact centers, helping organisations transition from legacy premise-based solutions to the cloud. The cloud contact center market has become the hot space for innovation in real-time communications, and is the tip of the spear for the application of Artificial Intelligence, especially Generative AI and Large Language Models (LLM). Our innovative AI team is responsible for developing a suite of leading edge AI products built upon industry-leading AI tech from vendors like OpenAI, Google, and Amazon. These products include enterprise voice and chatbots (think: ChatGPT for businesses), agent assistance, and conversation analytics. This team - the fastest growing at Five9 - is seeking a talented and experienced Senior Front End React/Redux Software Engineer. In this role, you will be part of the team that builds software that brings AI technologies to users. Prior AI experience is not required - you will receive on-the-job experience for some of the hottest skills on the market. An ideal candidate for us is an experienced engineer who is passionate about building high performance web platforms and applications, a brilliant problem solver and a creative self-starter.

Key Responsibilities:

- Implement UX designs by working with UX Designers on a day-to-day basis, using React/Redux based framework.
- Build custom widgets for dashboards developed using Google Looker Studio plugins.
- Be part of an agile team to develop a scalable, highly available application platform using modern PaaS platforms such as GCP.
- Participate and contribute to requirements analysis and grooming.
- Understand how to leverage PaaS components, such as CDN, noSQL databases when developing software in order to achieve scalability, reliability, and operability.
- Document and communicate clearly architecture and implementation solutions.
- Have ownership of your code in production, including on-call, troubleshooting.

Key Skills:

- 5+ years software development experience.
- React/Redux focus.
- Highly proficient in JavaScript and TypeScript.
- Experience in operational code ownership – on-call, troubleshooting, uptime
- Experience in applying modern UI design patterns and separating concerns in a distributed system.
- Must have experience working within an Agile/Scrum team.
- Positive, self-motivated and enthusiastic attitude with a strong sense of ownership.
- Strong pro-active communication skills, both verbal and written.
- Experience in contact center software is a plus but not required.
- Experience with custom widget development using Google Looker Studio is a plus but not required.

Workplace location: This role is fully remote for candidates who reside outside Porto, Maia, Matosinhos, Gondomar, Valongo e Vila Nova de Gaia.  Candidates who reside within those municipalities would be required to work in-office 3 days a week.

Benefits:

- Five9 Shares
- Bonus Scheme
- 10% Flexi Benefit
- Meal Allowance
- Medical Insurance
- Life Insurance
- 25 day Annual Leave + Public Holidays

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.

View our privacy policy, including our privacy notice to California residents here: https://www.five9.com/pt-pt/legal.

Note: Five9 will never request that an applicant send money as a prerequisite for commencing employment with Five9.

## About Five9

## Company Overview
- **One-liner**: Five9 provides a leading cloud contact center platform (CCaaS) that enables organizations to deliver digital engagement, analytics, workforce optimization, and AI-powered customer experiences.
- **Entity Type**: Public (NASDAQ: FIVN)
- **Headquarters**: San Ramon, California, USA (with additional offices in San Francisco, Toronto, London, Munich, Porto, Madrid, São Paulo, and Mandaluyong City)
- **Founded**: 2001
- **Founders**: Not publicly available

## Core Business
- **Primary industry/industries**: Cloud Contact Center as a Service (CCaaS), Customer Experience (CX) software, AI & Automation, Workforce Optimization
- **Target customers**: Enterprise, mid-market, and SMB organizations across all verticals (B2B/B2C)
- **Mission or purpose statement**: “Our vision is to make customer service a more human experience.” [five9.com](https://www.five9.com/about)

## Products & Services
- **Five9 Cloud Contact Center Platform**: Core omnichannel contact center solution (voice, email, chat, SMS, social) with intelligent routing and IVR.
- **Digital Engagement**: Integrated digital channels including SMS, web chat, email, and social messaging.
- **Five9 Analytics**: Real-time and historical reporting, speech analytics, and sentiment analysis to improve agent performance and customer outcomes.
- **Workforce Optimization (WFO)**: Workforce management, quality management, and recording (acquired Virtual Observer in 2021).
- **AI & Automation Suite**:
  - **Intelligent Virtual Agent (IVA)**: Conversational AI chatbot and voice bot for self-service (acquired Inference Solutions in 2021).
  - **Agent Assist 2.0**: AI-powered real-time agent guidance and summarization (using OpenAI).
  - **Voice AI Agents**: Generative AI agents for automated customer interactions.
- **Professional Services**: Implementation, integration, and consulting services.
- **Aceyus VUE**: Data and reporting integration platform (acquired in 2022).

## Market Standing
- **Valuation/Market Cap**: Publicly traded; specific metrics not provided in available sources.
- **Key Metric**: Over 3,000 customers worldwide; 350,000+ agents using the platform; 2,600+ employees; 1,450+ technology and channel partners. [five9.com](https://www.five9.com/about)
- **Notable Investors/Partners**: BT (expanded partnership for cloud adoption), MCM Telecom, XTT Mexico; partners include global SIs and technology vendors. Acquisitions: Acqueon, Aceyus VUE, Inference Solutions, Virtual Observer.
- **Growth Signals**: Named a Leader in the 2025 Gartner® Magic Quadrant™ for CCaaS (8th time); opened new European engineering hub in Porto, Portugal; expanded LATAM partnerships; introduced Agent Assist 2.0 with AI Summary; won Glassdoor Employees’ Choice Award for Best Places to Work (2022). [five9.com](https://www.five9.com/about)

## Competitive Advantages
- **Cloud-native heritage**: Born in the cloud in 2001, with 20+ years of CCaaS experience.
- **Analyst recognition**: Consistently named a Leader in Gartner Magic Quadrant, Forrester Wave, IDC MarketScape, and Aragon Research Globe.
- **High customer satisfaction**: 86 Net Promoter Score (NPS) for professional services.
- **Comprehensive AI portfolio**: Integrated IVA, Agent Assist, and Voice AI Agents differentiate from competitors.
- **Scale and reliability**: Manages billions of call minutes annually across 2,600+ concurrent agent seats (average).

## Strategic Focus
- **AI-first innovation**: Continued investment in generative AI and conversational AI to automate and enhance customer interactions.
- **Global expansion**: Strengthening presence in LATAM (new partnerships), EMEA (engineering hub in Portugal), and APAC.
- **Platform depth**: Integrating acquisitions (Acqueon, Aceyus, Inference Solutions) to provide end-to-end CX and WFO capabilities.
- **Partner ecosystem**: Deepening relationships with systems integrators and telcos (e.g., BT) to accelerate cloud migration.

## Why Work Here
- **Culture**: Fast-paced, start-up-like environment with established enterprise customers; values include honesty, respect, inclusion, transparency, ownership, and customer focus. [five9.com](https://www.five9.com/about/careers)
- **Diversity & Inclusion**: Committed to a diverse and inclusive culture where employees are empowered and heard. [five9.com](https://www.five9.com/about/careers/jobs)
- **Remote/Hybrid Policy**: Not explicitly stated; offices in multiple locations suggest hybrid/office model.
- **Benefits** (US full-time): 100% employer-paid health insurance (choice of 4 medical plans), dental, vision, life/disability insurance, 401(k), FSA, employee assistance program, commuter discounts, company equity, accrued PTO + paid holidays, company events. [five9.com](https://www.five9.com/about/careers)
- **Recognition**: Received Glassdoor Employees’ Choice Award for Best Places to Work (2022). [five9.com](https://www.five9.com/about)
- **Growth opportunities**: Internship program with impactful work and exposure to executives; career paths across development, customer success, sales, marketing, finance, and professional services.

## Sources
1. [Five9 About Page](https://www.five9.com/about)
2. [Five9 Careers Overview](https://www.five9.com/about/careers)
3. [Five9 Fact Sheet](https://www.five9.com/resources/five9-company-fact-sheet)
4. [Five9 Careers – Job Listings](https://www.five9.com/about/careers/jobs)

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