Vapi (@Vapi_AI) is the platform for building and deploying voice AI agents. It now serves about a billion calls a year for companies including Amazon, Uber, and Intuit, helping businesses automate phone calls with AI. Voice is becoming the default interface between businesses and their customers, but getting agents reliable enough for production is still much harder than it looks. In this episode of Founder Firesides, co-founders @jordan_dearsley and @nikhilro_ sit down with @gustaf to share the long path to product-market fit, from pivoting more than a dozen times to building an AI therapist that eventually became the foundation for Vapi. They explain why voice was the first idea that felt inevitable, and how sticking with that conviction before the technology was ready eventually paid off. 00:05 — Powering a billion calls a year 02:12 — Why voice AI suddenly started working 04:57 — More than a dozen pivots 09:08 — From calendar app to AI note taker 13:23 — Starting over in San Francisco 14:14 — The AI therapist that became Vapi 17:56 — Finding PMF 22:47 — Why the model labs won’t replace Vapi 26:49 — The future of voice AI

We’re excited to announce that Andy O'Dower, VP and Field CTO at @Twilio, will be speaking at VapiCon 2026! Andy leads the work of turning agentic AI into production communications infrastructure. He partners with Twilio's R&D and go-to-market leadership on the platform's AI direction, and previously ran product for Voice, Video, and Flex, used by millions of developers and generating hundreds of millions in annual revenue. Andy was a Twilio customer before he was a Twilio executive, having built on the platform at venture-backed startups and public companies. He has spent more than 20 years building software platforms and the teams behind them. Join us in San Francisco this November to hear Andy and other industry leaders discuss the future of Voice AI. 📍 Fort Mason, San Francisco 📅 November 11–12, 2026 🎟️ Get your ticket: vapicon.ai/

We've been testing @typesafeai Jev against real problems in voice AI. Member of Technical Staff @ashwinalaparthi built a guardrail that checks responses while speech generates: no added latency. Caught at least 3 of 4 violations. Here's what we learned: vapi.ai/blog/early-experimen…

We’re excited to welcome Phonic as a Startup Sponsor of VapiCon 2026! Phonic is the platform for building, evaluating, and deploying voice AI agents that sound like real conversations. Its speech models are designed for human-like emotion, timing, and nuance, with low-latency responses and natural interruption handling. We’re thrilled to have the Phonic AI team joining the Voice AI community at VapiCon. Join us November 11–12 at Fort Mason in San Francisco as the voice AI community connects, builds, and launches what’s next. Learn more and purchase your VapiCon 2026 ticket at vapicon.ai/

We’re excited to welcome @Modulate_ai as a Startup Sponsor of VapiCon 2026! Modulate is a voice intelligence company building AI models and APIs designed to understand real-world conversational audio at scale. Its technology combines speech recognition, acoustic analysis, and conversational context to deliver reliable, explainable, and cost-effective voice intelligence for developers and enterprises. We’re thrilled to have the Modulate AI team joining the Voice AI community at VapiCon. Join us November 11–12 at Fort Mason in San Francisco as the voice AI community connects, builds, and launches what’s next. Learn more and purchase your VapiCon 2026 ticket at vapicon.ai

We're thrilled to announce that @grinich, Michael Grinich, is going to be speaking at VapiCon 2026! Michael is the Founder and CEO of @WorkOS, a developer platform powering enterprise features for leading AI companies—including OpenAI, Anthropic, Perplexity, and Cursor—as well as hundreds of other modern SaaS applications. Join us in San Francisco this November as Michael and other industry leaders discuss the future of Voice AI. 📍 Fort Mason, San Francisco 📅 November 11–12, 2026 🎟️ Get your ticket: vapicon.ai/

When we hosted VapiCon last year, voice AI was early. Today it's production-ready, and teams are deploying at scale with results that speak for themselves. VapiCon shows you what's next. Fort Mason, SF · Nov 11–12, 2026. Registration is open: vapicon.ai

Voice agents with a view at @Vapi_AI @DeepgramAI rooftop party in Barcelona 🥳

Please join us in welcoming Neil Zeghidour, Co-founder CEO of @GradiumAI, as a Speaker at VapiCon 2026! Neil founded Gradium after a decade of building and leading frontier generative audio teams at Meta and Google DeepMind. Being frustrated by slow and brittle voice assistants, he built the engineering teams that developed the first neural audio codecs and introduced the first audio LLMs, such as AudioLM, at Google. He later created Kyutai to launch Moshi, the world's first real-time, full-duplex conversational AI, and Hibiki, the first simultaneous speech-to-speech translation system. Today, Gradium is focused on helping developers build natural, real-time voice agents by providing ultra-low latency streaming APIs that transition these breakthroughs from the research lab to production. Join us in San Francisco this November as Neil and more industry leaders come together to delve into the future of Voice AI. 📍 Fort Mason, San Francisco 📅 November 11–12, 2026 🎟️ Get your ticket: vapicon.ai/

Tomorrow I'm hosting some of our mysteriously absent from X engineers - Mhar Andal, Scott Lowe, Adham El Fawal. They will be going deep into platform primitives they shipped here at @Vapi_AI and answering questions about Model Intelligence, Simulations, and Campaigns. RSVP here: luma.com/ofrq557i Can't join live? RSVP anyway and we'll send you the replay.

We’re excited to welcome @CekuraAI as a Startup Sponsor of VapiCon 2026! Cekura is the reliability layer for voice agents, helping teams test before launch, monitor real production calls, and continuously improve. Its platform runs synthetic conversations, surfaces failures, reproduces issues in simulation, and helps teams validate fixes before the next release. We’re thrilled to have the Cekura team joining the Voice AI community at VapiCon. Join us November 11–12 at Fort Mason in San Francisco as the voice AI community connects, builds, and launches what’s next. Learn more and purchase your VapiCon 2026 ticket at vapicon.ai

We’re thrilled to announce that @kwindla, Kwindla Hultman Kramer, CEO at @trydaily, is returning as a speaker for VapiCon 2026! Kwindla is a network engineer, co-founder of infrastructure company Daily, and part of the team behind Pipecat, the open-source real-time AI framework. Join us in San Francisco this November as Kwindla and more industry leaders delve into the future of Voice AI. 📍 Fort Mason, San Francisco 📅 November 11–12, 2026 🎟️ Get your ticket: vapicon.ai/

The frontier voice AI summit is back. Two days at Fort Mason, Nov 11 and 12. Speakers from Deepgram, LangChain, Vercel, Cartesia, Daily, Coval, Arize Twilio, Soniox, and more to come. Who's speaking and why we're excited: vapi.ai/blog/the-frontier-vo… Tickets at vapicon.ai

We're sponsoring Knowledgefest, Out-Of-Pocket's healthcare ops conference, October 16-17 in San Francisco! We'll be demoing and sticking around for the day. If you'll be there, come find us to talk about improving patient experience with voice AI!

You changed one line in the prompt. You have no idea what else was affected. A voice agent can answer the same caller three different ways. One good test call isn't evidence you can depend on for production. Swipe to learn best practices for testing voice agents so you can be confident every update works. Full write-up → docs.vapi.ai/test/voice-test…

VapiCon is 8 weeks away. Time to make the trip official! We'll be at Fort Mason's Festival Pavilion in San Francisco this November with the builders, product leaders, operators, and teams shaping the future of voice AI. Grab your ticket, book your travel, and plan your stay nearby before discounted hotel rates close on October 11. Recommended travel dates: November 10-13. 📍 Fort Mason, San Francisco 📅 November 11–12, 2026 🎟️ Get your ticket: vapicon.ai/ ✈️ Book your travel: vapicon.ai/book-your-stay Our Amazing Sponsors: Deepgram, Krisp, Oxylabs, AssemblyAI, pyannoteAI, Speechmatics, Cekura, Modulate, Phonic, Hamming AI, Roark, ai-coustics

We’re thrilled to announce that @seldo, Laurie Voss, Head of Developer Relations at @ArizeAI, is joining us as a speaker for VapiCon 2026! Laurie Voss is Head of Developer Relations at Arize AI, the leading company for AI observability and evaluations. He has been a developer for over 30 years and was co-founder of npm, Inc. He believes passionately in making the web bigger, better, and more accessible for everyone. Join us in San Francisco this November as Laurie and other leaders in the Voice AI discuss the future of the industry. 📍 Fort Mason, San Francisco 📅 November 11–12, 2026 🎟️ Get your ticket: vapicon.ai/

Supporting a language and working in it are not the same thing. Catch us at HumanX Europe in Amsterdam at booth F19, to get into what that actually takes. Latency budgets. Interruption handling. What breaks when you go from one language to four. Plus: Vapi is hosting dinner at Shakerato, alongside Reson8 🇺🇸 🇬🇧 🇿🇦 who build speech recognition tuned to more than 20 European languages. 📍 RAI Amsterdam, Booth F19 📅 September 22-24, 2026 🎟️ Dinner RSVP, by approval: luma.com/d7jixwna?utm_source…