Introducing VEXYL - AI Voice Gateway for FreePBX/Asterisk Systems

Hey FreePBX community,

I’m Anil, and I’ve been working on a voice AI gateway that bridges FreePBX/Asterisk to modern AI services (STT, LLM, TTS) without ripping out your existing telephony infrastructure.

What is VEXYL?

VEXYL is a self-hosted middleware that sits between your Asterisk/FreePBX system and AI providers. It connects via AudioSocket protocol and handles the entire voice AI pipeline - speech recognition, LLM processing, and text-to-speech - while your PBX continues managing call routing, billing, and all the telephony logic you’ve already built.

Why I Built This

After deploying voice AI for healthcare systems in India, I realized there’s a massive gap between “expensive cloud per-minute platforms” and “build everything yourself.” Organizations with existing PBX investments shouldn’t have to choose between $0.15-0.40/min cloud costs or spending months building custom integrations.

Key Technical Details:

  • Protocol: Asterisk AudioSocket (also planning SIP support)

  • Architecture: Redis for session/cache

  • Response Times: 2.2-3.3 seconds end-to-end (STT→LLM→TTS)

  • TTS Caching: 90% hit rate, reduces repeated responses to 2ms

  • Providers: 17+ AI providers supported (bring your own keys)

  • Languages: 100 + 10+ Indian languages (Malayalam, Hindi, Tamil, etc.)

  • Deployment: Self-hosted binary or Docker, complete data sovereignty

Real-World Usage:

Currently processing 1000+ patient interactions monthly for healthcare systems - appointment reminders, callback confirmations, all in local India language. 95% satisfaction rates.

Two Operating Modes:

  1. Standard Mode: Full pipeline (STT→LLM→TTS) with custom data integration

  2. Gateway Mode: Direct audio streaming to OpenAI Realtime API, ElevenLabs

Current Capabilities:

  • Inbound call handling

  • Outbound calling with pre-warmed greetings (eliminates 3-5 sec initial delay)

  • Context-aware conversations

  • Multi-provider failover

  • Circuit breakers and retry logic

  • TTS response caching

  • Session management across transfers

On the Roadmap:

  • FreeSWITCH compatibility

  • FCC SIP 603+ compliance (March 2026)

Pricing Philosophy:

Tiered licensing based on concurrent calls (10/20/50 channels), with BYOK model. Goal is 87-91% cost savings vs building in-house, 95% vs custom dev.

Why Post Here?

The FreePBX community understands telephony infrastructure better than anyone. I’d love feedback on:

  • Integration patterns you’d want to see

  • Use cases you’re encountering

  • Technical concerns about AudioSocket vs other approaches

  • Provider preferences for STT/TTS/LLM

Not Here to Spam

I’m genuinely looking for feedback from folks who’ve “been there, done that” with PBX systems. If this doesn’t fit your needs, no worries - but if you’re exploring voice AI integration, happy to discuss technical approaches.

Website: https://vexyl.ai

Would love to hear your thoughts, especially from anyone who’s tackled similar integration challenges.