I need a voice platform that can do IVR, transfer to agents, transcribe calls, and stream audio to my backend. Any recommendations?

Yes — you’re looking for a programmable voice/contact-center platform with:

• IVR / call flows
• Call transfer / warm transfer to agents
• Call transcription
• Real-time audio streaming to your backend

A few strong options:

Best general-purpose options

1) Twilio Voice + Media Streams

Good if you want maximum flexibility and a strong developer ecosystem.

• IVR/call routing: yes
• Transfers to agents: yes
• Transcription: yes, via Twilio or your own STT
• Real-time audio streaming: yes, via Media Streams
• Pros: very flexible, lots of docs/examples, easy to integrate with custom backend
• Cons: can get pricey; you assemble more pieces yourself

2) Vonage Voice API

Good programmable voice platform with real-time media capabilities.

• IVR: yes
• Transfers: yes
• Transcription: yes, via integrations
• Audio streaming: yes, supports webhook/media events and RTC-style integrations
• Pros: good APIs, solid international coverage
• Cons: ecosystem not as large as Twilio

3) SignalWire

Good if you want programmable telephony with more control and potentially lower cost.

• IVR: yes
• Transfers: yes
• Transcription: yes, via integrations
• Audio streaming: yes
• Pros: developer-friendly, often cost-effective
• Cons: smaller ecosystem than Twilio

Contact-center oriented options

4) Amazon Connect

Best if you want a fuller contact-center product rather than building everything yourself.

• IVR: yes
• Transfers: yes
• Transcription: yes, via Amazon Transcribe / Contact Lens
• Streaming to backend: possible via integrations/contact flows and event streaming patterns
• Pros: strong transcription and analytics, scalable
• Cons: more opinionated; less “raw” control than a pure API platform

5) Genesys Cloud / Five9 / Talkdesk

Better if you want an enterprise contact center with agent tools built in.

• IVR: yes
• Transfers: yes
• Transcription: yes
• Streaming audio: sometimes supported via APIs/partners, but usually less straightforward than Twilio-style media streams
• Pros: complete CCaaS stack
• Cons: heavier, more expensive, less custom-backend friendly

If your top priority is audio streaming to your backend

I’d shortlist:

1. Twilio Voice + Media Streams
2. SignalWire
3. Vonage Voice API

If you want transcription tightly integrated and a more turnkey contact center:

1. Amazon Connect
2. Genesys Cloud

My practical recommendation

• If you’re building a custom voice app and need the backend to process live audio: Twilio is usually the default choice.
• If you want a contact-center platform with agent workflows: Amazon Connect.
• If you want to optimize for cost/control: SignalWire is worth a look.

A few questions to narrow it down

1. Do you need live audio streaming in real time, or is post-call transcription enough?
2. Are agents in a browser app or an existing system like Zendesk/Salesforce?
3. Do you need outbound calling too, or inbound only?
4. Any preference for US-only vs global coverage?
5. Do you want HIPAA/SOC 2/PCI support?

If you want, I can give you:

• a feature-by-feature comparison table
• a recommended architecture
• or a shortlist based on your stack and budget.