Senior CCaaS Telephony Engineer

Position OverviewWe are seeking an 8+ year Senior CCaaS Telephony Engineer with deep expertise in Five9 Contact Center deployments to lead the architecture, implementation, and system integrations for enterprise contact center transformation in Frederick, MD. In this role, you will design and maintain High-Level and Low-Level Designs (HLD/LLD in Visio), develop resilient IVR workflows and intelligent routing strategies, build API integrations connecting Five9 with Salesforce CRM and enterprise platforms, and navigate the technical solutions through the Architecture Review Board (ARB).Key ResponsibilitiesFive9 Platform Configuration: Architect, configure, and administer Five9 cloud capabilities, including voice, digital engagement channels, skill-based queues, and workforce engagement/optimization tooling.IVR & Intelligent Routing: Design, build, and optimize custom Interactive Voice Response (IVR) architectures, call flows, automation rules, and SIP/VoIP routing logic.Architecture & Governance: Author and maintain architectural artifacts (HLD/LLD in MS Visio), design specifications, and test evidence; represent telephony solutions across the Architecture Review Board (ARB) process.Enterprise API Integrations: Build, deploy, and maintain RESTful APIs and middleware to integrate Five9 seamlessly with Salesforce Service Cloud, WFM/WFO platforms, databases, and AWS/Azure cloud services.Telephony Troubleshooting: Diagnose complex issues across SIP signaling, telephony trunks, routing rules, network latency, and integration payloads; execute comprehensive unit, regression, and end-to-end integration testing.Cross-Functional Collaboration: Partner with Program Directors, Telephony Engineers, Enterprise Architects, and operations leadership to ensure operational readiness and reliable support handoffs.Required Qualifications8+ years of progressive experience in software engineering, platform engineering, or technology delivery with extensive hands-on enterprise Five9 Contact Center implementation depth.IVR & Call Routing Mastery: Proven experience building complex Five9 IVR scripts, call distribution trees, and omnichannel digital routing.Telephony & VoIP Protocols: Solid understanding of telephony protocols, SIP routing logic, network infrastructure, and telecom troubleshooting.API Development & Integration: Strong hands-on experience developing RESTful APIs and connectors with at least two of the following: Java, .NET, Python, or Cloud Services (AWS / Azure).Architecture Documentation: Ability to translate business outcomes into formal High-Level Design (HLD) and Low-Level Design (LLD) diagrams using Microsoft Visio.Work Arrangement: Must be able to work 100% onsite in Frederick, MD from Day 1.Preferred QualificationsOfficial Five9 Certifications (Administrator, Implementation, or Developer).Deep experience integrating Five9 with Salesforce Service Cloud / Salesforce CRM.Exposure to Workforce Management (WFM) and Quality Assurance (QA/WFO) platforms.Bachelor’s degree in Computer Science, Engineering, Information Systems, or a related field.