Telephony Infrastructure Engineer

Salient; San Francisco (CA); On-site; USD 150,000 - 190,000; Full time

Benefits offered by this job

Medical, Dental, Vision coverage

401(k) plan

Catered lunches

In-office SF collaboration

Job summary

Salient is hiring a Telephony Infrastructure Engineer to own the voice platform behind our AI agents—SIP edge, Asterisk, voice audio and dialing layers, and the call servers that connect borrowers to our agents. You will work closely with AI agent engineers, telephony specialists, customer success, and carriers.

This is a hands-on ownership role. You will finish work in flight, make the platform reliable and safe to change, and design customer telephony integrations to be increasingly

Qualifications

• Production voice infrastructure experience at scale and on-call readiness.
• Deep knowledge of SIP/SDP/RTP and debugging from traces/pcaps.
• Ability to diagnose EC2/Kubernetes networking issues and design robust monitoring/testing.

Responsibilities

• Finish the Asterisk migration with zero regression and retire legacy paths.
• Ensure reliability of voice audio and dialing layers with SLOs and incident response.
• Enable zero-downtime call-server deployments with safe rollout and rollback.
• Build tools to manage Kamailio and Asterisk reconfiguration inside Kubernetes.
• Implement backpressure, load shedding, and self-recovery when dependencies degrade.

Skills

SIP

Asterisk

Kamailio/OpenSIPS

Kubernetes

Real-time media

Networking (EC2/K8s)

Load testing

Runbooks/Postmortems

Job description

About Us

Salient builds AI agents for regulated financial services. Our agents automate loan servicing, compliance, collections, recovery, insurance claims, and disputes for banks, captives, and specialty lenders.

We are:

• Backed by a16z and Y Combinator, with $75M raised in Series A funding
• Cash flow positive and profitable, with mid eight figure ARR achieved in under two years
• Already serving more than 20% of the auto lending industry
• Processing millions of real customer calls and transactions every day
• Fully deployed in production with major financial institutions
• Actively expanding into new financial services segments
• Building together in person in San Francisco

We are deeply integrated with our customers, own the full technology stack, and move quickly to bring modern AI into regulated industries where precision, reliability, and performance matter.

About the Role

We're hiring a Telephony Infrastructure Engineer to own the voice platform behind Salient's AI agents: the SIP edge, Asterisk, the voice audio and dialing layers, and the call servers that connect borrowers to our agents. You will work directly with our AI agent engineers, telephony specialist, customer success, and carriers.

This is a hands‑on ownership role. You will finish work in flight, make the platform reliable and safe to change, and prove it can handle the next order of magnitude of call volume. You will also design and implement customer telephony integrations and make them increasingly self‑serve.

What You’ll Own

• Finishing the Asterisk migration: cutting over remaining customers, trunks, and call flows with no regression, then retiring the legacy path.
• Reliability of the voice audio and dialing layers: SLOs, monitoring, incident response, and eliminating recurring failure modes.
• Zero‑downtime call‑server deployments: draining, graceful shutdown, safe rollout, and rollback without dropping live calls.
• Building tools to manage Kamailio and Asterisk reconfiguration without server restarts inside Kubernetes
• Backpressure, load shedding, and self‑recovery when carriers, media, or AI dependencies degrade.
• Load testing and capacity planning that validates thousands of concurrent calls and CPS at the SIP edge.
• Voice observability: call‑quality and platform‑health metrics, alerting, runbooks, and postmortems.
• Security of the voice edge against scanning, toll fraud, and abuse.
• Customer telephony integrations: custom SIP trunks (e.g., Genesys, Bandwidth), call transfers, SIP header passing, and API prototypes with new contact‑center platforms.
• Self‑serve setup: productized trunk configurations, validation tooling, and docs that shorten time to go live.

What We’re Looking For

• You've run production voice infrastructure at meaningful scale and have been on call for it.
• You know SIP, SDP, and RTP deeply and debug from traces and pcaps.
• You can debug EC2/K8s networking issues that result in deadair—and develop monitoring and testing plans to minimize deadair.
• You understand real‑time media, WebRTC, and latency budgets.
• You design for backpressure, graceful degradation, and safe deploys of stateful services.
• You've built load tests that found real bottlenecks before customers did.
• You write clear design docs, runbooks, and postmortems.
• You've integrated SIP trunks with customer contact centers and carriers, including transfers and header passing.

Nice to Have

• Experience with Kamailio, Asterisk, OpenSIPS, FreeSWITCH, or rtpengine.
• Experience developing regional failover for SIP
• Experience with latency‑aware multi‑homing
• Experience with contact‑center, dialer, CpaaS, or carrier infrastructure.
• Experience with AI voice agents, speech pipelines, or regulated industries such as lending.
• Experience with contact‑center platforms such as Genesys, Five9, NICE, or Amazon Connect.

Why This Role

Every Salient product depends on a phone call working. You will own the platform that carries those calls and make it reliable, easy to change, and ready for the volume our customers are about to send it.

At Salient, we’re building at the edge of AI - fast, focused, and with real ownership. Sprints and major launches move quickly, and we look for people who are energized by that pace. Our team typically works around 60 hours per week, beginning at 8:00 AM, with four days spent collaborating in person at our San Francisco office.

We also offer a benefits package designed to support our full‑time employees: medical, dental, and vision coverage, a generous 401(k), and catered lunches.