Intermediate/Senior Product Engineer

Symend is building a voice agent that calls people who are past due on bills, explaining their situation and negotiating payment arrangements in real time. The role involves owning the full product lifecycle, leading a small delivery team, and ensuring the product meets market needs.

Responsibilities:

• You’ll own the full lifecycle of that product: pre-sales conversations where you help a client understand what’s possible, discovery where you find the real job-to-be-done, and implementation where you build and ship it
• You’ll lead a small delivery team, one to two junior and intermediate engineers, operating on a parallel track to the core platform
• What you learn feeds back into the roadmap
• What you ship is the conversational product
• You’ve built real agentic pipelines
• You understand context window constraints, tool call patterns, failure modes, and what happens when an agent loses the thread mid-call
• You should be able to explain where your last pipeline broke and why
• Hands-on experience with at least one of: Twilio, ElevenLabs, Retell, or Deepgram
• You know why real-time audio is technically hard – latency, media streaming, session state – and you’ve built something that had to work under those constraints
• You write async Python with confidence: asyncio, FastAPI, SQLAlchemy async
• You’re comfortable in TypeScript/React and can work across the frontend, but you don’t need to be a specialist there
• You know how to run a conversation that surfaces the real problem, not just the stated one
• You can translate a messy client requirement into a scoped technical approach and explain it back to a non-technical stakeholder without losing the room
• You’ve wired up external APIs, dealt with inconsistent documentation, rate limits, and auth schemes, and made it reliable
• Webhooks are the primary integration pattern for Twilio, ElevenLabs, and Retell
• You’ve built webhook receivers, implemented HMAC signature validation, handled replay attacks, and designed for idempotency
• You’ve used Redis as more than a cache: pub/sub, streams, session state at scale
• You use AI as a drafting partner, not a decision-maker
• You reach for it on boilerplate, test scaffolding, and exploration
• You own the design
• You know when the output needs to be thrown out
• You’ve built multi-tenant SaaS where tenant data bleed is a real threat, not a hypothetical, and you can describe specifically how you prevented it
• Per-tenant credential scoping, namespaced keys, org-scoped access patterns are second nature
• You’ve shipped to cloud-hosted containers
• You can read a GitHub Actions workflow, understand why a build fails in CI but works locally, and debug a deployment without needing someone to translate the logs
• You’ll become expert in it
• Not just as a user, but as someone who understands its capabilities well enough to identify where it falls short and push it forward

Requirements:

• Minimum 3 years experience building SaaS products at scale
• LLM orchestration depth is the floor
• Voice AI and telephony familiarity
• Full-stack implementation capability
• Client-facing discovery skills
• Integration and event-driven architecture
• AI tooling philosophy
• Multi-tenant systems experience
• Cloud deployment literacy
• Agentic SDLC toolkit fluency
• B2B experience is an asset