Senior Programmable Voice Engineer (CX Platform)

We are looking for a Senior Programmable Voice Engineer to develop programmable voice capabilities, call control services, media processing, and API-driven communications infrastructure similar to Twilio and other CPaaS platforms. The role includes designing and building the voice platform powering next-generation customer experience solutions using technologies such as FreeSWITCH, Kamailio, SIP, WebRTC, Java, and Spring Boot. It suits a senior engineer who can move confidently between architecture, code, delivery risk, non-functional requirements, and client-facing technical discussions.

Responsibilities:

• Design and develop programmable voice services, APIs, and call-control capabilities for enterprise-scale communications platforms.

• Build and extend voice infrastructure using FreeSWITCH, Kamailio, SIP, RTP, WebRTC, and related technologies.

• Design and develop backend services and communication APIs using Java and Spring Boot to expose voice capabilities to internal and external applications.

• Implement call routing, session management, media handling, carrier integrations, and voice traffic processing solutions.

• Design highly available, scalable systems capable of handling large volumes of real-time communications traffic.Troubleshoot complex signaling, media, telephony, and call-quality issues across distributed environments.

• Integrate voice services with contact center, routing, digital engagement, CRM, identity, and reporting platforms.

• Define non-functional requirements for availability, performance, concurrency, security, privacy, observability, disaster recovery, and supportability.

• Review designs and code, identify technical risks, challenge assumptions, and drive pragmatic decisions that balance quality, time, and cost.

• Establish engineering standards, reusable patterns, quality gates, documentation expectations, and technology adoption guidance.

• Collaborate with client stakeholders, Product, Architecture, QA, DevOps, Security, Operations, and vendors to govern delivery and resolve critical technical issues.

• 8+ years of software engineering experience, including substantial ownership of architecture and technical delivery for distributed applications.

• Deep hands-on expertise with FreeSWITCH and/or Kamailio, including call control, dial plans, media services, ESL, modules, and platform customization.

• Experience building API-driven communication platforms, voice services, or CPaaS-style solutions.Strong knowledge of voice infrastructure and real-time communications, including SIP, RTP, WebRTC, session control, media handling, and telephony troubleshooting.

• Expert-level hands-on experience with Java, Spring Boot, microservices, REST APIs, persistence, security, testing, and performance engineering.

• Deep understanding of API-first design, event-driven architecture, messaging, distributed systems, and cloud-native engineering.

• Experience with PostgreSQL or comparable relational databases, data modeling, integration data flows, and transactional design.

• Hands-on experience with contact center or CX platforms and the operational concepts behind customer routing and engagement.

• Excellent communication skills, including the ability to produce clear technical documentation and lead client-facing workshops.

Nice to Have

• Experience with OpenSIPS, Asterisk, Twilio, SignalWire, or comparable communications platforms.

• Experience building routing engines, IVR platforms, voice bots, or omnichannel engagement services.

• Experience with Genesys, NICE, Five9, Amazon Connect, Cisco, Avaya, or comparable contact center platforms.

• Familiarity with Kafka or RabbitMQ, Kubernetes, Jenkins, observability platforms, API gateways, and security architecture.

• Practical experience with AI-assisted software development or AI-enabled solutions, including tools such as Claude or GitHub Copilot, is a plus.

We offer:

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