Senior Backend Engineer – Communications (USA Only - 100% Remote)

Close • ,

6d • $140,000 - $210,000 • Remote

About The Position

The Communications team at Close owns the entire surface area for handling millions of call recordings, sales emails, and SMS messages monthly. This role has become more complex due to the integration of real-time AI into live calling. The team is looking for an engineer who is energized by both distributed systems challenges and AI challenges. Engineers at Close often move between teams, so this role is a starting point with opportunities to work on various projects over time. This position is open at multiple levels: Software Engineer, Senior, and Staff, with calibration happening during the hiring process.

Requirements

• Seasoned engineer with experience in Python, and potentially Go, Rust, or TypeScript, choosing the right tool for the workload.
• Deeply experienced with email and calendar platforms, including IMAP, sync protocols, calendar APIs, and enterprise mail server edge cases.
• Fluent in real-time and async distributed systems (WebRTC, WebSockets, queues, streaming) and debugging production incidents related to latency.
• Opinionated about AI in real-time workflows, with experience building or using live transcription, voice agents, or in-the-loop AI features.
• Comfortable with telephony providers, codecs, retries, and eventual consistency; experience with edge cases in these systems.
• Experience using AI tools in daily workflows to improve speed, code quality, and understanding of codebases.
• A builder mentality, prioritizing shipping a functional version 1 over extensive abstraction.
• Experience with AI tools in your day-to-day workflow.

Nice To Haves

• Deep Twilio or similar telephony experience is a big plus.

Responsibilities

• Overhaul how Close syncs email and calendars, investing in the performance and reliability of the sync engine.
• Expand voice agent capabilities and infrastructure for live conversations, including custom models for voicemail and automated phone-tree detection.
• Develop inbound call handling capabilities, including specialized agents, a receptionist layer, and seamless call routing.
• Build native scheduling capabilities within Close and for agents.
• Design human orchestration for an agentic workforce, determining how to surface relevant information within the CRM.
• Improve connect rates and answer rates through phone number pooling, local presence, branded calling, and reputation monitoring.
• Advance the streaming and event substrate using Kafka, Redis, and pub/sub.

Benefits

• Opportunity to work on challenging distributed systems and AI problems.
• Potential to work on multiple different projects and teams over time.
• Calibrate role level (Software Engineer, Senior, Staff) during the process.
• Company values: Build a house you want to live in, No BS, Invest in each other, Discipline equals freedom, Strive for greatness.
• Team gatherings for connection, collaboration, and fun (e.g., 2023 team retreat in Milan, upcoming in Dusseldorf, Germany).

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed