Lead Engineer

### **About Blue Machines**

Blue Machines builds Voice AI and Agentic Automation systems that change how enterprises around the world interact with AI. Our platform runs live voice conversations at global scale, combining real\-time telephony, in\-house AI models and multi\-agent orchestration. We're a world\-class team building real\-time systems that push the limits of latency and reliability.

### **Role Overview**

We're looking for a Lead Engineer to own the real\-time voice and telephony platform that powers live AI conversations at Blue Machines. You'll set the technical direction for everything from the carrier and SIP trunk to the AI agent: signalling, media, streaming ASR/TTS and the latency budget across all of them.

This is a hands\-on leadership role. You'll spend most of your time (around 50–70%) designing and building, while leading and mentoring a team of 3–6 engineers.

### **Responsibilities**

• Own the end\-to\-end architecture of the voice and telephony stack, covering SIP signalling, media servers, WebRTC and call routing from the carrier to the AI agent.
• Design and run real\-time media pipelines (FreeSWITCH, Asterisk, Kamailio or LiveKit) that stream audio to ASR, LLM and TTS within tight end\-to\-end latency budgets.
• Lead carrier and telephony\-provider integrations: SIP trunks, DIDs, number provisioning and multi\-provider failover.
• Drive call quality and reliability across codecs, jitter, packet loss, echo and barge\-in. Define and own SLOs for latency, uptime and call success rate.
• Scale the platform for high call concurrency through capacity planning, autoscaling of media workloads on Kubernetes and cost per call minute.
• Set the engineering bar for the team: lead system design, review code and designs, make build\-vs\-buy calls and manage tech debt.
• Lead and mentor a team of 3–6 engineers. Plan and break down work, grow engineers through feedback and take part in hiring.
• Own production health for live call traffic, including observability (Datadog, Sentry), on\-call, incident response and postmortems.
• Partner with product and AI teams on the platform's multi\-agent orchestration and automation layer.
• Work closely with the ML team to integrate in\-house models, drive benchmarking and evaluation, and help build the next generation of in\-house AI models.

• *Requirements**

### **Must\-Have Skills**

• 7–10 years of backend development experience in Python or Java, including time spent building high\-scale, low\-latency real\-time systems.
• Proven experience as a tech lead: guiding a team through design and delivery, mentoring engineers and staying hands\-on in the codebase while leading a team of 3–6 engineers.
• Deep, hands\-on expertise in SIP, RTP/SRTP, SDP and WebRTC.
• Has built or operated media and signalling stacks such as FreeSWITCH, Asterisk, Kamailio/OpenSIPS or LiveKit in production.
• Experience with carrier integrations and SIP trunking, plus CPaaS providers such as Twilio, Exotel or Plivo.
• Strong grasp of audio codecs and NAT traversal, and debugging call quality using tools such as Wireshark or sngrep.
• Experience shipping Voice AI in production: streaming ASR/TTS, real\-time inference and end\-to\-end latency tuning.
• Experience integrating LLMs, vector DBs or AI agent frameworks into production systems.
• Strong command of system design, concurrency and distributed systems, with a track record of owning architecture decisions.
• Experience with cloud infrastructure, databases, and message queues, plus containerized deployments with Kubernetes and Docker.
• Eligible to work in India.

### **Good to Have**

• Prior work leading AI\-driven or telephony\-driven platforms at scale.
• Experience building contact\-centre, IVR or outbound dialer systems.
• Experience collaborating with ML/research teams on model benchmarking, evaluation or observability.
• Contributions to open\-source telephony or WebRTC projects.