Build the platform behind Managed Agents, shaping the latency, reliability, and developer experience of real-time voice agents.
Posted by employer 5 months ago
First seen on Joblaze 1 month ago
Last verified on the company career page 18 hours ago
Skills & Technologies
AI in the day-to-day
null
Requirements
- Visa
- Sponsorship available
Not disclosed in this posting: compensation, years of experience.
Benefits
Joblaze summary
In this role, the Software Engineer will focus on developing the platform that supports Managed Agents, ensuring the performance and reliability of real-time voice models. Key skills include experience with distributed backend systems and a strong understanding of customer-facing metrics like latency and reliability. This position is ideal for someone with a background in high-growth startups who can communicate effectively across technical and non-technical teams. Cartesia's emphasis on rapid execution and a collaborative culture highlights its commitment to innovation in AI.
Joblaze insights
- Listed about a month ago — first seen on Joblaze September 3, 2026. Last confirmed on Cartesia's careers page October 27, 2026.
- distributed systems appears in 5.8% of 260 comparable mid backend roles in United States; WebRTC appears in 0.8% of 260 comparable mid backend roles in United States.
Quick facts
- Is the Software Engineer, Agent Harness role remote?
- No — this is an on-site role in *HQ - San Francisco, CA.
- Where is the role based?
- Cartesia is hiring for this position in *HQ - San Francisco, CA.
- What's the tech stack?
- Joblaze extracted these technologies from the posting: RTP, SIP, WebRTC, agent frameworks, distributed systems, low-latency audio.
- Does Cartesia sponsor work visas for this role?
- Yes — the posting indicates visa sponsorship is available for the right candidate.
- What seniority level is this role?
- Cartesia targets mid-level candidates for this position.
- Is this full-time or contract?
- Full-time for this Software Engineer, Agent Harness role at Cartesia.
From the original posting
About the Role
Cartesia builds real-time multimodal intelligence: fast, state-of-the-art voice models, and the platform that puts them into production. We started as a research lab, pioneered the state space model architecture, and now we're bringing that research to customers through Managed Agents, our voice agents product.
In this role, you'll build the platform behind Managed Agents. Customers rely on our stack to run real-time, production-grade voice agents. You'll own the stack end-to-end and directly shape the latency, reliability, and developer experience of every agent built on Cartesia.
Your Impact
Evolve the realtime transport layer that carries audio between users and agents, expanding how customers connect across web, SDKs, and telephony without regressing latency or quality.
Trace and cut end-to-end conversational latency across the STT, LLM, and TTS pipeline.
Make agent deployments fast and resilient: faster cold starts, smarter scaling, graceful behavior under load.
Define how voice agent quality is measured, building eval suites, LLM-as-judge scoring, and regression tracking that catch quality and latency regressions before they ship.
What You Bring
Experience building and operating distributed backend systems in production, ideally at a high-growth startup. We care more about what you've shipped than strict years of experience.
Strong product instincts: you think in customer-facing latency, reliability, and developer experience, and you have opinions on what to build and why.
Fluent use of coding agents and a habit of keeping pace with the frontier.
Clear communication with technical and non-technical audiences, sharp specs, and a strong presence in design reviews.
Nice-To-Haves
Experience with real-time media systems in production, including WebRTC, SIP, RTP, or low-latency audio.
Experience with voice agents or agent frameworks such as Pipecat, LiveKit, OpenAI Agents SDK, Claude SDK, or Vercel AI SDK.
Experience building developer-facing platforms or infrastructure, such as SDK backends or API platforms.
Experience with distributed systems at scale, including high-throughput workloads, autoscaling, multi-region architectures, or queue-based systems.
🏦 401(k)
🦖 Your own personal Yoshi
Standard company text repeated across Cartesia's postings is omitted here.