openring

About openring

openring is an open-source tool for running voice AI agents on your own infrastructure. It speaks a Vapi-compatible API, so existing clients can switch by changing a base URL. The software handles AI phone agents through Twilio, Telnyx, Plivo, Vonage, or SIP - using your own API keys - and also includes a fully local, free mode that runs on Whisper, Ollama, and Kokoro without per-minute platform fees.

Review

openring enters a space where most hosted voice-agent platforms charge by the minute. It puts the stack on your own hardware, which shifts cost and control to the user. The trade-off is that you also take on the operational responsibility.

Key Features

• Vapi-compatible API - clients built for Vapi can connect to openring by changing the base URL
• Self-hosted deployment on your own computer or server, using your own API keys
• Carrier integration with Twilio (tested on real calls), plus Telnyx, Plivo, Vonage, and SIP in beta
• Free local mode that runs entirely offline with Whisper, Ollama, and Kokoro
• No platform fee - you pay only for the third-party services you bring

Pricing and Value

openring itself is free and open-source. There is no per-minute platform fee. Your costs come from the third-party services you connect - LLM providers, transcription services, and telephony carriers - all using your own keys. If you run the fully local mode with Whisper, Ollama, and Kokoro, the voice pipeline can operate at zero additional cost beyond your hardware.

Pros

• Eliminates the per-minute platform fee that hosted voice-agent services charge
• Vapi-compatible API reduces the effort of migrating existing integrations
• Local mode keeps all data on your own hardware, which matters for sensitive use cases
• Carrier flexibility - Twilio is confirmed working, with several others available in beta
• Full source code access lets teams audit, modify, or extend the system

Cons

• Requires self-hosting skills - you handle deployment, scaling, and uptime on your own infrastructure
• Telnyx, Plivo, Vonage, and SIP support are still in beta, so production reliability on those carriers isn't yet established
• Not well suited for teams that want a managed service with SLAs and hands-off maintenance

openring fits teams that already run their own servers and want to cut the recurring per-minute costs of hosted voice agents. It also makes sense for projects where data locality is a hard requirement. Teams without DevOps capacity or those who need carrier support beyond Twilio right now may want to wait until the beta integrations mature.