Hi everyone,

I’ve been working on a side project that uses a voice AI agent (built with Retell AI) to automate outbound sales calls and customer support. Since this community values technical depth, I wanted to share the architecture, the engineering challenges I hit, and hear how others have tackled similar issues.

🛠️ Architecture & Stack

• Retell AI → real-time call handling, speech-to-text + TTS, intent routing
• Make.com → workflow orchestration, retries, automation
• CRM + Google Sheets → datastore for leads, logging call results

The goal was: an AI agent that can instantly call back leads, answer FAQs, transfer complex calls to humans, and log everything in the CRM in real time.

⚡ Key Challenges & Solutions

1. Latency / Call Flow

2. Problem: Even small delays break the illusion of a natural voice conversation.

3. Attempted Fix: Cached common responses, used pre-fetching for likely intents, parallelized some flows.

4. Scaling Concurrent Calls

5. Problem: Multiple outbound calls triggered at once caused dropped connections.

6. Fix: Added a lightweight job queue to throttle outbound calls and balance across workers.

7. CRM Sync Reliability

8. Problem: Direct API calls to CRM sometimes hit rate limits.

9. Fix: Batched writes into small intervals (<30s) to keep “real-time enough” while avoiding throttling.

10. Failure Recovery

11. Problem: Network drops or agent handovers created call loops.

12. Fix: Built retry + dead-letter queue logic for failed calls.

📊 Early Observations

• Lead response time dropped from hours → seconds.
• Support team offloaded repetitive FAQ calls.
• Human handover still needs a smoother UX (customers sometimes confused if AI → human wasn’t seamless).

❓ Questions for the Community

• For those who’ve built real-time voice systems → how do you consistently keep latency under \~300ms?
• Any proven patterns for scalable API orchestration beyond Make.com?
• How do you handle CRM sync when transactions fail mid-call?

I’d love to hear how other experienced devs here have approached similar real-time system challenges. I can also share code snippets or more architecture details if anyone’s curious.