Principal Software Engineer - Real-Time Voice

About Parloa Parloa’s mission is to make every customer conversation feel effortless for both customers and the companies serving them. As agentic AI accelerates, Parloans are shaping the foundation of a new era in customer experience, one where customer support is no longer transactions, but meaningful exchanges. It is not just a vision; Parloa has powered over ONE BILLION interactions between global enterprise brands and their customers, with companies like Booking.com , HealthEquity, Allianz, SAP, BarmeniaGothaer, and TUI already deploying Parloa at scale. About the role: Voice is one of the most demanding and differentiated parts of what we do. As Principal Software Engineer for Voice/VoIP, you'll own the technical direction of our real-time voice infrastructure — the systems that let AI agents have natural, low-latency phone conversations at enterprise scale, across telephony providers, carriers, and global markets. This is a hands-on technical leadership role. You'll set architectural direction, solve the hardest problems yourself, and raise the bar for how the wider engineering org builds and reasons about voice systems. You'll work closely with infrastructure, AI/ML, and product teams to ensure our voice stack is fast, reliable, and ready to scale globally. Areas of ownership: Own the architecture and technical roadmap for Parloa's Voice/VoIP infrastructure, including SIP trunking, media handling, and real-time audio pipelines Design for low-latency, high-availability voice at enterprise scale — across global telephony carriers and providers Drive technical decisions on protocols and standards (SIP, SDP, RTP/SRTP, RTCP, WebRTC, ICE, STUN/TURN) and real-time media transport Partner with AI/ML teams to optimise the integration between voice infrastructure and conversational AI models (ASR, TTS, turn-taking, barge-in) Diagnose and resolve deep, systemic issues in call quality, latency, jitter, and packet loss across distributed, multi-region deployments Define and uphold engineering standards for reliability, observability, and security across the voice stack Mentor senior and staff engineers, acting as a technical multiplier across the organisation Evaluate and integrate with telephony providers, carriers, and SIP trunk vendors as Parloa expands into new markets Represent Parloa's technical voice expertise in conversations with enterprise customers and partners where needed Who you are: 10+ years of engineering experience, including 5+ years hands-on building, operating, or debugging production Voice/VoIP, SIP, WebRTC, or carrier-grade voice infrastructure Strong knowledge of SIP, SDP, RTP/SRTP, RTCP, WebRTC, ICE, and real-time media transport protocols Hands-on understanding of audio codecs and media behavior, including Opus, G.711/G.722, codec negotiation/transcoding, DTMF/RFC2833, jitter buffers, packetization, and codec-related quality/latency trade-offs Experience building or operating large-scale, distributed, real-time systems with strict latency and availability requirements A track record of owning architecture for complex systems and driving technical decisions with broad organisational impact Experience working with telephony carriers, SIP trunk providers, or PSTN integrations at scale Deep, hands-on ownership of production SIP-based voice infrastructure at enterprise scale (e.g. Kamailio, FreeSWITCH, Asterisk, pjsip) Strong systems programming skills in one or more of Go, C, C++ or Rust, with the ability to work at the media/transport layer. Comfort operating in cloud environments (AWS, GCP, or Azure) and with container orchestration (Kubernetes) Excellent communication skills — able to explain complex technical trade-offs to engineers and non-engineers alike A genuine interest in AI and conversational technology, and how voice infrastructure underpins it Experience instrumenting and operating voice-quality observability — call-quality metrics (e.g. MOS), per-leg call tracing, and diagnosing jitter, latency, and packet loss from telemetry Our engineering values: At Parloa, we hire, promote, and evaluate based on cultural and technical excellence. You’ll thrive here if you: Earn Trust – act with transparency and reliability. Obsess Over Customers – always start with the customer problem. Think Big – set bold goals and pursue them fearlessly. Have Integrity – do the right thing, especially when it’s hard. Disagree & Commit – debate with candor, align fast, and deliver. Own It – take full responsibility for outcomes, not just tasks. Dive Deep – master the details without losing sight of the big picture. Bias for Action – move fast, decide quickly, iterate fearlessly. Deliver Value – measure success by customer and business impact. Insist on the Highest Standards – raise the bar continuously. Go the Extra Mile – make the impossible possible. Hire & Elevate the Best – raise the bar with every hire O