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Phone-Response AI SaaS

Speech-to-Speech (STS) AI Phone-Response Service Development

Joined development of a phone-response AI SaaS combining LLMs with speech synthesis. Designed a voice platform that balances natural conversational experience with real-time responsiveness.

Apr 2026 –·Role: SES development
PythonSpeech SynthesisLLMSTS

Challenge

  • Phone responses cannot tolerate seconds of silence, requiring parallel LLM streaming responses and speech synthesis.
  • Misrecognition / clarification fallbacks must be implemented naturally.
  • Encrypted call-log storage and high-precision PII masking are required.

Solution

  • Pipelined STT → LLM streaming response → speech synthesis, achieving sub-1-second latency to first response.
  • Attached confidence scores to speech recognition; auto-injected clarification prompts on low confidence.
  • Auto-applied recording encryption and PII masking (names, phone numbers, address patterns).

Technology Decisions

Why Python on the backend

The voice and ML library ecosystem is concentrated in Python; direct handling beats other-language wrappers for debuggability.

Outcomes

Time to First Response

< 1 second

STT → LLM streaming → TTS pipeline achieves gap-free perception

Recognition Accuracy

95%+

Industry-term dialogue; auto-clarification on low confidence score

PII Masking

Names / phone / address patterns auto-applied

Applied before encrypted recording storage

Call-Log Encryption

At-rest + in-transit

AES-256 + TLS 1.3

Team

1 of our engineers (SES) + client-side team

Have a similar requirement?

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