Senior Backend Engineer – Communications

Senior Backend Engineer enhancing AI-driven call solutions for communications team. Overhauling sync engines, expanding voice agent capabilities, and improving real-time workflows.

Posted 7/16/2026full-timeRemote • 🇺🇸 United StatesSenior💰 $140,000 - $210,000 per yearWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates expertise in Python and experience with Go, Rust, or TypeScript for building robust systems. Proficient in real-time and async distributed systems, with a strong understanding of email and calendar platforms, telephony, and AI integration.

Highest-signal resume keywords

Python ProgrammingEmail And Calendar PlatformsReal-Time And Async Distributed SystemsAI Integration In WorkflowsTelephony Experience

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

PythonGoRustTypeScriptIMAPWebRTCWebSocketsKafkaRedisSync Protocols

Soft Skills

Problem SolvingCollaborationAdaptability

Tools & Technologies

TwilioStreamingEvent SubstrateVoice AgentsLive Transcription

Industry Keywords

TelephonyEdge CasesLatency BudgetsBranded CallingCall Routing

Tech Stack

Tools & technologies

Distributed SystemsGoKafkaPythonRedisRustTypeScript

About the role

Key responsibilities & impact

Overhaul how Close syncs email and calendars. Our sync engine has run for a decade; we're making a serious, ground-up investment in its performance and reliability.
Take voice agents further into the call. We own the live conversation layer for Chloe's calls, and there's a lot of work ahead expanding our voice agent capabilities and infrastructure.
Solve inbound. So far Chloe makes calls; next she answers them. An inbound conversation can go anywhere — which raises real questions about specialized agents, a receptionist layer, and seamless call routing between them.
Build native scheduling. Core calendar scheduling capabilities inside Close, plus more powerful scheduling for our agents.
Design human orchestration of an agentic workforce. Agents create work for humans too — things to review, approve, respond to.
Push connect rates and answer rates. Phone number pooling, local presence, branded calling, reputation monitoring.
Move our streaming and event substrate forward. Kafka, Redis, pub/sub.

Requirements

What you’ll need

A seasoned engineer. Python is our backbone, but perhaps you've worked across Go, Rust, or TypeScript. You pick the right tool for the workload rather than retreating to what you know.
Deeply experienced with email and calendar platforms. IMAP, sync protocols, calendar APIs, and the thousand edge cases of oddly configured enterprise mail servers. This is the experience that makes someone successful on this team fastest.
Fluent in real-time and async distributed systems. WebRTC, WebSockets, queues, streaming. You've debugged a production incident where latency budgets didn't hold.
Opinionated about AI in real-time workflows. You've built or used live transcription, voice agents, or in-the-loop AI features. You have a view on what's ready for production versus what's still a demo.
At home in the gnarly bits. Telephony providers, codecs, retries, eventual consistency. You're drawn to the systems where edge cases actually matter. Deep Twilio or similar telephony experience is a big plus (not a requirement — but a game changer off the bat).
Working with AI in your day-to-day. You use AI tools in your own workflow to ship faster, write tighter code, and reason about unfamiliar parts of the codebase.
A builder first. You'd rather get a sloppy v1 in front of fifty customers than spend three weeks on abstractions. You ship.

Benefits

Comp & perks

Health insurance
401(k) matching
Flexible work hours
Paid time off
Remote work options