Bolna

Bolna is an end-to-end open-source voice agents platform built by Whismurwave Inc. and backed by Y Combinator. It orchestrates voice conversations by combining ASR, LLM, and TTS providers over WebSockets, and ships with both a self-hostable framework and a hosted API/dashboard layer. The platform is specifically designed for Indian language support, covering 10+ vernacular languages including Hindi, Hinglish, Tamil, and Telugu.

What It Is

Bolna is a production-ready framework for building LLM-based voice-driven conversational applications. At its core, it is a Python orchestration engine that chains together speech recognition, language model inference, and text-to-speech synthesis to power inbound and outbound phone calls. The open-source repository (MIT-licensed) forms the backbone of Bolna's hosted APIs and no-code dashboard, which are built on top of it but remain closed source.

Architecture: Three-Layer Stack

The platform is structured in three layers that build on each other:

• Open-source orchestration engine — the GitHub repository handles agent creation, provider routing, WebSocket streaming, and telephony integration
• Hosted REST APIs — a managed API layer built on the open-source core, documented at docs.bolna.ai
• No-code UI playground — a dashboard at platform.bolna.ai for building and deploying agents without writing code

This means developers can self-host the full stack, use the hosted APIs programmatically, or use the no-code interface — all three paths share the same underlying engine.

Supported Providers and Integrations

Bolna connects to a wide range of third-party providers across every layer of the voice pipeline:

• Telephony: Twilio, Plivo, Exotel (coming soon), Vonage (coming soon)
• ASR (speech-to-text): Deepgram, Azure
• LLM: OpenAI, DeepSeek, Llama, Cohere, Mistral, and others via LiteLLM
• TTS (text-to-speech): AWS Polly, ElevenLabs, Deepgram, OpenAI, Azure, Cartesia, Smallest
• Workflow tools: n8n, Make.com, Zapier

BYOK (Bring Your Own Keys) is supported for LLM, TTS, and ASR providers, allowing cost control by routing through personal API keys.

Target Audience and Use Cases

Bolna is positioned for both developers and non-technical builders in India and globally. The platform ships pre-built agent templates for:

• E-commerce: cart abandonment recovery, COD confirmation, customer support
• EdTech: student engagement and support
• Recruitment: AI-driven candidate screening and interviews
• BFSI and Hospitality: collections, surveys, and booking flows

The vendor publishes case studies citing customers including Awign, Hyreo, GoKwik, Hypothesis, and Futwork, with claims such as 400,000+ unique engagements and 10,000+ daily calls for specific deployments.

Update: Version 0.10.86

The latest release on GitHub is version 0.10.86, published on June 11, 2026, with the repository last pushed on June 12, 2026. The project shows active maintenance with 666 stars and 299 forks as of mid-2026. The README notes the team is actively looking for additional maintainers. A changelog is maintained at bolna.ai/docs/changelog and the project continues to expand provider support and API surface area. A community event — the Bolna x Cartesia Voc-a-thon — was announced for June 13, 2026, signaling active developer community engagement.