Senior Full Stack Engineer (Realtime & Voice) Customer Experience Platform
Full Stack Engineer · Senior · Full Time · Remote
Opens Hopper's application page
Role
What you'll do.
Senior Full Stack Engineer role at Hopper's HTS Assist, an agentic AI assistant for travel customer support. You'll own the realtime voice and chat platform end-to-end, architecting WebRTC/telephony integrations, streaming speech pipelines, and multi-tenant backend services using React/TypeScript, Scala, Python, and GCP. This is a high-impact position in a lean, senior team where you'll design for enterprise scale, build safety/compliance systems, and maintain revenue-critical deployments serving millions of travelers globally.
Responsibilities
- Voice Channel Architecture & Ownership: Own the voice channel end-to-end from customer phone call to agent/AI response, including telephony platform integrations (Twilio, Amazon Connect), CPaaS orchestration, streaming speech-to-text pipelines, streaming text-to-speech synthesis, real-time model inference routing, and continuous latency and quality budget optimization to deliver sub-100ms perceived latency.
- Full-Stack Product Feature Development: Design and ship features across the entire technology stack: React/TypeScript web chat interfaces for travelers, Scala and Python backend services handling customer interactions and business logic, and GCP infrastructure supporting multi-region deployment and high availability requirements.
- Multi-Tenant Platform Scaling: Design and implement multi-tenant architecture serving diverse enterprise partners (airlines, hotels, travel agencies) with a single codebase using configuration-driven customization rather than code forks, ensuring isolation, performance, and seamless partner onboarding.
- Enterprise Security & Compliance Infrastructure: Build and maintain safety systems including conversation guardrails, inappropriate content filtering, automatic PII redaction, compliance audit trails, and configurable security integration points that enable enterprise partners to pass customer security and regulatory audits.
- Production Health & Revenue Protection: Ensure revenue-critical systems remain healthy and performant through comprehensive observability (logging, tracing, metrics), intelligent alerting tied to business SLAs, rapid incident response and triage, blameless post-mortems, and continuous deployment quality improvements.
- Partner Enablement Platform: Build self-service platform capabilities and documentation that enable forward-deployed engineers to configure telephony integrations, customize voice behaviors, manage deployment rollouts, and troubleshoot issues for partner go-lives without requiring core team intervention.
- Engineering Excellence & Mentorship: Raise the engineering quality bar through thorough code reviews focusing on production readiness, architecture design reviews for new systems, technical mentorship of junior engineers, and establishing coding standards and best practices that scale across the team.
- Real-time System Optimization: Continuously optimize latency, throughput, and reliability of real-time systems handling millions of concurrent customer interactions. Profile bottlenecks, implement performance improvements, manage resource allocation, and maintain comprehensive performance monitoring dashboards.
Qualifications
What we look for.
Technical
React/TypeScript Frontend Development
Build production-grade web interfaces for real-time chat and communication. Must handle dynamic state, streaming updates, and responsive design for millions of concurrent users.
Backend Services (Scala & Python)
Design and implement scalable backend services with deep understanding of JVM performance tuning, async patterns, and Python ecosystem. Experience with Spring Boot, Play Framework, or FastAPI preferred.
WebRTC & Voice Streaming
Hands-on experience integrating WebRTC, implementing audio streaming pipelines, and orchestrating real-time voice communication. Understanding of codecs, bandwidth management, and quality metrics.
GCP/AWS Infrastructure
Architect and deploy systems on Google Cloud Platform or AWS. Experience with managed services, networking, data pipelines, and infrastructure automation using Terraform or similar tools.
RESTful API & Microservices Design
Design APIs that balance flexibility with performance. Implement service boundaries, versioning strategies, and backward compatibility patterns for multi-tenant systems.
Database & Data Pipeline Design
Experience selecting and optimizing appropriate database technologies (SQL, NoSQL, streaming) for different use cases. Understanding of schema design, indexing, and query optimization at scale.
Observability & Monitoring
Implement comprehensive logging, distributed tracing, and metrics collection. Set up alerting strategies and dashboards that catch production issues before they impact users.
Education
Bachelor's Degree in Computer Science or Related Field
Preferred but not required. Equivalent practical software engineering experience and demonstrated mastery of computer science fundamentals may substitute.
Experience
6+ Years of Production Software Engineering
Minimum six years of professional software engineering experience with proven ownership of production systems handling real customer traffic and measurable business impact.
Senior-Level Full-Stack Ownership
Demonstrated track record of leading full-stack features from design through deployment, including frontend, backend, infrastructure, and operational components.
Real-time Systems Production Experience
Hands-on experience shipping and maintaining real-time applications such as voice services, WebRTC applications, streaming platforms, or comparable low-latency products in production.
Microservices & Distributed System Design
Proven ability designing, building, and maintaining distributed architectures at scale. Experience with eventual consistency, asynchronous patterns, and managing deployment complexity across services.
On-Call & Operational Excellence
Demonstrated experience with production support, on-call rotations, incident response, and maintaining SLAs. Understanding of rollback strategies, canary deployments, and feature flags.
Cross-Functional Technical Leadership
Strong communication and collaboration across engineering, product, design, and operations teams. Ability to make pragmatic tradeoffs and advocate for technical decisions to non-technical stakeholders.
Skills
Required
React & TypeScript
Advanced proficiency building responsive, real-time web interfaces with React and TypeScript. Experience with state management, performance optimization, and building chat or communication interfaces at scale.
Backend Systems Architecture
Hands-on experience designing and maintaining production backend services in Scala, Python, or other JVM languages. Proven ability to build scalable microservices, RESTful APIs, and event-driven systems.
Real-time Systems Development
Demonstrated experience with low-latency, real-time applications such as WebRTC, VoIP, SIP, streaming media, or comparable voice/video products. Understanding of protocol handling, stream processing, and synchronization challenges.
Cloud Infrastructure & DevOps
Production experience on GCP or AWS with infrastructure-as-code, containerization, monitoring, and deployment pipelines. Ability to design for multi-tenant architectures and handle observability at scale.
Full-Stack Ownership
Track record of owning features and systems across the entire stack—from frontend UX through backend services to cloud infrastructure. Comfortable with operational responsibilities including on-call rotations and incident response.
Distributed Systems & API Design
Deep experience designing RESTful APIs, microservices architectures, and event-driven systems. Understanding of consistency models, eventual consistency, asynchronous patterns, and integration complexity.
System Observability & SRE Mindset
Strong operational discipline with hands-on expertise in structured logging, distributed tracing, metrics collection, alerting strategies, and SLA management. Proficiency in tools like Datadog, Prometheus, or ELK stack.
Preferred
Conversational AI & LLM Orchestration
Nice to haveExperience building with large language models, prompt engineering, and real-time inference pipelines. Familiarity with LLM frameworks like LangChain or platforms like OpenAI, Anthropic, or open-source models.
Speech Technology Stack
Nice to haveWorking knowledge of speech-to-text and text-to-speech technologies such as Deepgram, ElevenLabs, Whisper, or OpenAI Realtime API. Understanding of audio streaming, codec selection, and quality metrics.
Cloud Telephony & CPaaS Platforms
Nice to haveHands-on experience integrating with Twilio, Amazon Connect, Genesys, LiveKit, or similar communication platforms. Understanding of SIP, PSTN routing, call control, and IVR design.
Enterprise Security & Compliance
Nice to haveExperience building guardrails, content filtering, PII redaction systems, and audit-trail infrastructure. Knowledge of compliance frameworks (GDPR, SOC 2, HIPAA) relevant to enterprise customer deployments.
Travel Industry Technology
Nice to haveFamiliarity with PSS (Passenger Service Systems), GDS (Global Distribution Systems), hotel PMS/CRS systems, or travel commerce platforms. Understanding of travel business workflows and integrations.
Customer Service & Contact Center Platforms
Nice to havePrevious experience building or integrating CRM, customer service, contact center, or workflow automation tools. Understanding of agent workflows, routing, escalation, and customer interactions.
AI-Assisted Development
Nice to haveProficiency using GitHub Copilot, Claude, or similar AI coding tools as part of daily workflow, with strong judgment to review, test, and own all generated code before deployment.
Compensation
Pay and benefits.
Base·USD 200,000 – 250,000
Equity·Stock options
Benefits
Unlimited Paid Time Off
Flexible PTO policy with unlimited vacation days, reflecting trust in autonomous work culture and work-life balance prioritization.
Generous Parental Leave
Above industry-standard parental leave benefits, providing extended time for family planning and childcare needs well beyond typical tech company offerings.
Comprehensive Health & Wellness Coverage
100% employer-paid Medical, Dental, and Vision insurance for employees, with additional access to Disability and Life Insurance, Health Reimbursement Accounts (HRA), and Dependent Care/Flexible Spending Accounts (DCA/FSA).
Retirement Planning
Access to company 401(k) plan with potential employer matching, supporting long-term financial security and retirement readiness.
Pre-IPO Equity Compensation
Competitive salary combined with meaningful stock options reflecting the company's pre-IPO status and upside potential, enabling employees to participate in long-term company value creation.
Travel & Lifestyle Benefits
Carrot Cash travel stipend enabling reduced-cost or free travel bookings through the Hopper platform, allowing employees to experience the product and save on personal travel expenses.
Remote Work Infrastructure
Work-from-home stipend plus on-demand access to professional co-working spaces through FlexDesk partnership, supporting flexible and productive working environments.
Entrepreneurial Culture & Growth Opportunity
Dynamic, risk-taking culture where innovation is encouraged, decisions are decentralized, and small high-performing teams drive massive business impact with direct visibility to leadership and strategic direction.
Full posting
Original listing.
About the Role
HTS Assist is Hopper's agentic AI assistant for travel, resolving flight changes, cancellations, refunds, and bookings over chat and voice for some of the world's largest travel brands. We're looking for a senior full stack engineer to anchor this product, owning the realtime and voice layer end to end while building across React/TypeScript front ends, Scala and Python services, and cloud infrastructure. The team is lean and senior, ownership is broad, and the path from your code to a traveler's phone call is short.
What would your day-to-day look like
Own the voice channel end to end, including telephony and CPaaS integrations (e.g., Twilio, Amazon Connect), streaming speech-to-text and text-to-speech pipelines, realtime model orchestration, and latency and quality budgets
Build product features across the stack, including web chat front ends in React/TypeScript, backend services in Scala and Python, and infrastructure on GCP
Design for multi-tenant scale, with one codebase serving many partners through configuration rather than forks
Build the safety and compliance plumbing enterprise partners audit, including guardrails, content filtering, and PII redaction integration points
Keep revenue-critical deployments healthy through observability, alerting, incident response, and SLA performance
Build the platform capabilities forward-deployed engineers configure for partner telephony integrations and go-lives
Raise the engineering bar through code review, architecture reviews, and mentoring
An ideal candidate has
6+ years of software engineering experience, with senior-level ownership of production systems and genuine full-stack range
Hands-on realtime systems experience, such as voice applications, WebRTC/SIP, streaming media, or comparable low-latency products
Strength in a modern front end (React, TypeScript) and depth on the backend (Scala or another JVM language, and/or Python), along with cloud infrastructure experience on GCP or AWS
A track record designing, building, and maintaining RESTful APIs, microservices, or event-driven systems
Familiarity using AI coding tools as a standard part of their workflow, with the judgment to review, correct, and own everything that ships
An operable-systems mindset, covering SLAs, observability, on-call rotations, and rollback plans
The ability to break down complex problems, make pragmatic tradeoffs, and ship iteratively, backed by strong communication across product, design, and operations
Bonus points for conversational AI or LLM orchestration experience, including speech technologies such as Deepgram, ElevenLabs, Whisper, or OpenAI Realtime
Bonus points for working knowledge of cloud telephony or CPaaS platforms such as Twilio, Amazon Connect, Genesys, or LiveKit
Bonus points for experience building customer service, CRM, contact center, or workflow automation tools
Familiarity with travel industry technologies (PSS/GDS, hotel PMS/CRS) is a plus, though not required
Perks and benefits of working with us
Well-funded and proven startup with large ambitions, competitive salary and the upsides of pre-IPO equity packages
Unlimited PTO
Carrot Cash travel stipend
Access to co-working space on demand through FlexDesk and a work-from-home stipend
Please ask us about our very generous parental leave, much above industry standards
Entrepreneurial culture where pushing limits and taking risks is everyday business
Open communication with management and company leadership
Small, dynamic teams, massive impact
100% employer-paid Medical, Dental and Vision coverage for employees
Access to Disability and Life insurance
Health Reimbursement Account (HRA)
DCA/FSA and access to a 401k plan
About Hopper
At Hopper, we are on a mission to become the leading travel platform globally, powering Hopper's mobile app, website and our B2B business, HTS (Hopper Technology Solutions). By leveraging massive amounts of data and advanced machine learning algorithms, Hopper combines its world-class travel agency offering with proprietary fintech products to bring transparency, flexibility and savings to travelers globally. We have developed several unique fintech solutions that address everything from pricing volatility to trip disruptions, helping people travel better and save more on their trips.
The Hopper platform serves hundreds of millions of travelers globally and continues to capture market share around the world. The Hopper app has been downloaded over 120 million times and has become largely popular among younger travelers, with 70% of its users being Gen Z and millennials.
While everyone knows us as the Gen Z and Millennial travel app, Hopper has evolved to become much more than that. In recent years, we've grown into a travel fintech provider, commerce platform, and global travel agency that powers some of the world's largest brands.
Through HTS, our B2B division, the company supercharges its partners' direct channels by integrating our fintech products on their sites or powering end-to-end travel portals. Today, our partners include leading travel brands like Capital One, Nubank, Air Canada, and many more.
Here are just a few stats that demonstrate the company's recent growth:
Billions of dollars worth of travel and travel fintech are sold through Hopper and HTS' channels every year.
Our fintech products, including Cancel for Any Reason and Flight Disruption Assistance, have exceptionally strong CSAT because the terms are always clear, and customers receive instant, no-questions-asked resolutions.
Almost 30% of our app customers purchase at least one fintech product when making a booking, and consumers are 1.6x more likely to repurchase if they add fintech to their booking versus if they booked just travel.
Given the success of its fintech products, Hopper launched a B2B initiative, HTS (Hopper Technology Solutions), which represents more than 75% of the business.
Through HTS, any travel provider (airlines, hotels, banks, travel agencies, etc.) can integrate and seamlessly distribute Hopper's fintech or travel inventory on their direct channels. As its first HTS partnership, the company partnered with Capital One to co-develop Capital One Travel, a new travel portal designed specifically for cardholders. Other HTS partners include Air Canada, Uber, CommBank, Nubank, Flair Airlines and many more.
Hopper has been named the #1 most innovative company in travel by Fast Company. Hopper has been downloaded over 120 million times and continues to have millions of new installs each month. Hopper is now the #3 largest online travel agency in North America and 70% of our app customers are Gen Z and millennial travelers.
Hopper has raised over $750 million USD of private capital and is backed by some of the largest institutional investors and banks in the world. HTS is primed to continue its growth as the leading travel ecommerce provider in a $1 trillion online shopping category. The Hopper app and website will also continue to be the preferred travel provider for Gen Z and Millennials.
Come take off with us!
#LI-Remote
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