Senior Infrastructure Engineer

Job Summary

As part of the CallMiner Engineering and Operations Team, the DevOps System Administrator is responsible for the reliability, security, and performance of the infrastructure that delivers CallMiner's intelligent CX automation solutions to enterprise customers, including OmniAgent.

The primary focus of this role is managing and supporting customer-facing infrastructure: deploying, operating, and troubleshooting the systems that connect AI virtual agents to customers' contact center and telephony environments. A central part of this responsibility is SIP telephony integration – owning the end-to-end technical path from the moment a customer's phone rings to the moment the AI agent answers, across SIP trunks, carriers, PBX systems, session border controllers, and enterprise networks.

The DevOps System Administrator partners closely with Engineering, Delivery, and Customer Success teams to support customer deployments, resolve infrastructure and connectivity issues, plan capacity, and ensure the availability of real-time, voice-first services handling millions of customer interactions annually. The ideal candidate is a proactive problem-solver who thrives on ownership and operational excellence in a fast-paced environment.

This position is based in Prague, Czech Republic, and supports CallMiner's Intelligent CX Automation platform serving customers throughout Europe and globally.

Responsibilities

• Administer, monitor, and maintain customer-facing cloud infrastructure (Azure and/or AWS, OVH Cloud) supporting CallMiner's intelligent CX automation platform
• Own SIP telephony integrations for customer deployments: configure and maintain connectivity via SIP trunking providers, direct trunks, and customers' enterprise telephony infrastructure (PBX, SBC, CCaaS platforms)
• Design reliable call paths balancing latency, audio quality, reliability, and security constraints
• Diagnose and resolve complex telephony and connectivity issues across customer environments, including call routing, NAT traversal, codec compatibility, RTP/audio quality, firewall and QoS configuration
• Ensure high availability, low latency, and resilience of real-time voice and conversational AI services
• Support customer onboarding and go-lives in coordination with Delivery and Professional Services teams, from proof-of-concept through production
• Manage containerized workloads and orchestration platforms (Docker, Kubernetes)
• Lead incident response and root cause analysis for infrastructure, telephony, and connectivity issues
• Perform routine system administration tasks including patching, backups, disaster recovery testing, user and access management, and capacity planning
• Harden systems and enforce security best practices, supporting compliance requirements (e.g., ISO 27001, GDPR, SOC 2) and audit activities
• Manage databases, networking, DNS, load balancing, certificates, and VPN/firewall configurations
• Collaborate with Engineering teams to translate recurring customer integration challenges into platform and process improvements
• Create and maintain clear technical documentation, runbooks, and integration guides for customer-facing infrastructure

Requirements

Requirements

• 5+ years of experience in System Administration, DevOps, VoIP/telephony engineering, or related infrastructure roles
• Bachelor's degree preferred in Computer Science, Information Technology, or related discipline, or equivalent practical experience
• Hands-on experience with SIP-based integrations, SIP trunking, call routing concepts, and real-world troubleshooting across networks and enterprise environments
• Strong Linux administration skills (Ubuntu/Debian/CentOS), including shell scripting (Bash) and scripting in Python or similar
• Hands-on experience with public cloud platforms (Azure and/or AWS), including compute, networking, storage, and identity services
• Practical experience with containerization (Docker) and orchestration (Kubernetes)
• Experience with monitoring, logging, and alerting tools and a structured approach to incident management
• Solid understanding of networking fundamentals (TCP/IP, DNS, VPN, firewalls, load balancing, NAT) and security best practices
• Strong troubleshooting and problem-solving skills with a proactive, ownership-driven mindset and direct customer impact
• Strong organizational skills, managing multiple priorities independently in a fast-paced, customer-facing environment
• Professional proficiency in Czech and English required

Preferred Experience

• Deep experience operating real-time communication infrastructure (VoIP, SIP, WebRTC, telephony platforms, session border controllers) or other latency-sensitive services
• Experience with SIP/VoIP diagnostic and analysis tools (e.g., Wireshark, sngrep, SIP tracing)
• Experience supporting conversational AI, contact center, CCaaS, or speech technology platforms (e.g., Genesys, Avaya, Cisco, Twilio, Vonage)
• Exposure to database administration (PostgreSQL, MySQL, MongoDB, Redis) and message queues (RabbitMQ, Kafka)
• Familiarity with security and compliance frameworks (ISO 27001, SOC 2, GDPR) in a SaaS environment
• Relevant certifications such as Azure Administrator Associate, AWS SysOps Administrator, CKA, or Linux (LPIC/RHCSA)
• Experience in a high-growth startup or scale-up environment, ideally within a multinational organization

Benefits

About CallMiner

Does the possibility of using artificial intelligence to improve human connection excite you? We agree!

CallMiner is the global leader in AI-powered conversation intelligence and customer experience (CX) automation. Our industry-recognized platform captures and analyzes 100% of omnichannel customer interactions delivering the insights organizations need to improve CX, enhance agent performance, and drive automation at scale. By combining advanced AI, industry-leading analytics, and real-time conversation intelligence, we empower organizations to uncover customer needs, optimize processes, and automate workflows and interactions. The result: higher customer satisfaction, reduced operational costs, and faster, data-driven decisions. Trusted by leading brands in technology, media & telecom, retail, manufacturing, financial services, healthcare, and travel & hospitality, we help organizations transform customer insights into action.

CallMiner's core set of values – from maniacal customer focus and radical candor to team mentality and transparency – serve as a touchstone for what we strive to create in a workplace culture and weave through everything we do as a company. We believe that by building a team of brilliant, inspired people, we can truly accomplish amazing things together. We are committed to providing an inclusive and equitable workplace where everyone feels accepted, valued, and understood.

Our strong commitment to a positive environment continually earns us recognition as a top workplace, including Boston Globe Top Place to Work.

Benefits + Perks

At CallMiner, we believe having a work-life balance is key to being able to deliver your best every day. Our perks are designed to enhance your daily work experience, promote your personal growth, and help you achieve a better work-life balance. From Maternity and Paternity Leave, ample Holidays, Fitness and Health Reimbursement, Tuition Reimbursement and more, we aim to provide an environment where you can thrive both professionally and personally.

We are an Equal Opportunity Employer that does not discriminate on the basis of actual or perceived race, creed, color, religion, ancestry, disability, sexual orientation, marital status, veteran status, gender identity, or any other characteristic protected by applicable federal, state, or local laws.