The 500ms Dash—Nikhil Gupta, VAPI

The 500ms Dash—Nikhil Gupta, VAPI

Nikhil Gupta is the cofounder and CTO of VAPI. He’s been in the trenches building and scaling one of the biggest voice platforms in the world. On this episode, he explains how VAPI aims to create a voice-default future where we talk to all our computers—and goes deep into every step of VAPI’s voice pipelines and the technical challenges along the way. Some highlights: ☎️ Massive scale: VAPI has processed 44 million voice calls on their platform, growing from a COVID-era one-click Zoom meeting button to a full voice infrastructure company used by thousands of developers. ⚡️ Latency matters: Voice AI needs to respond within 500 milliseconds to feel natural to humans. That means cleaning audio, detecting when users are done speaking, transcribing text, generating responses, converting to speech, and handling interruptions—all within a fraction of a second. 🗣️Voice-first future: Nikhil is betting a future where voice becomes our default interface with all computing systems. If you’ve ever wondered how voice API actually works—this is the episode for you. Chapters 00:00 - Introducing VAPI 04:42 - Pivoting through COVID 05:42 - ChatGPT existential crisis 08:33 - Technical challenges of voice 12:42 - Anatomy of a voice call 14:46 - Knowing when someone is done speaking 18:37 - Routing to the fastest model 22:07 - Knowledge and context injection 26:47 - The text-to-speech bottleneck 31:14 - Handling interruptions gracefully 33:43 - The 500-millisecond barrier 36:56 - The DNS latency discovery 39:25 - Scaling the team and what's next Links * VAPI [https://vapi.ai/] * Nikhil Gupta on LinkedIn [https://www.linkedin.com/in/nikhilro/] * VAPI on Product Hunt [https://www.producthunt.com/products/vapi] * Stratechery by Ben Thompson [https://stratechery.com/] - Recommended reading from Nikhil This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit www.smartspeakers.fm [https://www.smartspeakers.fm?utm_medium=podcast&utm_campaign=CTA_1]

Your AI interviewer will see you now—Varun Khurana, Wayfaster

Varun Khurana wants every job candidate to have the best possible chance to prove themselves for every job they apply to. He’s been in the trenches building with voice AI for 2+ years, and had some great nuggets to share: * 💬 How Wayfaster started: “Wayfaster started out as a way to interview your entire pipeline in a couple seconds... the only way you can really do that is using voice AI." * ⛔️Why AI video avatars are a no-go: "We tried avatars and every candidate hated it... I think it just makes candidates feel dumb. It's just like, why am I talking to an avatar? Like how stupid do you think I am?" * 📑How AI interviews give candidates a chance: "Candidates have just gotten really accustomed to getting this default auto-reject email... At least here, I know that if I do a good job on the interview, I have a shot at this opportunity." * 🐻Why he’s bearish consumer voice AI: "I'm actually a little more bearish on the consumer voice AI use cases. I like voice AI in constrained environments, like B2B, there's an amount of intent... I don't think people are going to want to be talking to their phones all the time." Hope you enjoy the conversation! As always you can subscribe at https://smartspeakers.fm. Chapters 0:00 Welcome and intro 1:32 First big AI aha moment 5:08 Career background 7:40 Exploring startup ideas 10:34 How WayFaster was born 14:21 Initial target markets 16:45 Candidate response to AI interviews 19:07 Benefits for recruiters and candidates 23:30 How AI is transforming recruiting 26:51 The two-sided recruiting game 31:05 Why Varun is bearish on consumer voice AI 35:09 Future generations and AI adoption 38:09 Content recommendations and closing Links * WayFaster Website [https://wayfaster.com]: wayfaster.com * Varun Khurana on LinkedIn [https://www.linkedin.com/in/vkhurana2/]: https://www.linkedin.com/in/vkhurana2/ [https://www.linkedin.com/in/vkhurana2/] * South Park Commons [https://www.southparkcommons.com/] * Deepgram [https://deepgram.com/] * Charles Rubenfeld's Newsletter [https://charlesrubenfeld.substack.com/] This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit www.smartspeakers.fm [https://www.smartspeakers.fm?utm_medium=podcast&utm_campaign=CTA_1]

The pipeline for voice—Kwindla Hultman Kramer, CEO of Daily

Much of my childhood was spent in my basement, dialing up other people’s computers to trade messages and play games. Kwin Kramer from Daily remembers that time, too—and says today's voice AI moment feels just like those early internet days. That sense of endless possibilities is back. His open-source project PipeCat has become the standard toolkit for voice agents. What began as an experiment now powers voice AI for OpenAI, Google DeepMind, and countless startups, making conversations feel natural and responsive. Some highlights: * That early internet feeling is back: "1995 to 1999 felt a certain way. It never felt that way again until 2023 to 2025." * GPT-4 transformed Daily's business by removing a key bottleneck: "Previously you needed two humans for a conversation. Now you only need one, maybe not even that." * Voice AI's killer feature? Latency matters: "If response times are long, you're in that uncanny valley where people get uncomfortable." * Kwin's bold prediction: "We're all going to have friends in our group chats that aren't human because LLMs are actually really entertaining." Hope you enjoy it as much as we did. Links Daily: https://daily.co/PipeCat: https://pipecat.ai/Kwin on Twitter: https://twitter.com/kwindla Chapters 0:00 Intro 2:02 First AI aha moment 5:43 MIT Media Lab beginnings 9:05 BBS and door games 15:26 The AllAfrica journey 18:54 Starting Daily 21:13 COVID's impact on WebRTC 22:36 GPT-4 transformation 31:26 Building voice for LLMs 35:17 PipeCat's key challenges 44:10 The future of speech-to-speech 47:10 Voice AI adoption trends 52:34 Vibe coding revolution 56:11 What's next for PipeCat This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit www.smartspeakers.fm [https://www.smartspeakers.fm?utm_medium=podcast&utm_campaign=CTA_1]

The craft behind voice AI magic with Tom Shapland

This week, Tom Shapland shares his journey from agriculture tech to founding Canonical, a tool that helps voice AI developers understand and improve conversations by mapping call stages. Tom has deep experience in the voice world—we loved this conversation and we’re sure you will too! Links https://canonical.chathttps://x.com/Tom_Shaplandhttps://www.linkedin.com/in/tom-shapland-b4494212/ Chapters 0:00 - Intro 1:05 - Welcome and first AI moment 3:03 - Computer vision for thirsty plants 5:50 - Explaining AI to farmers 7:52 - Hardware is hard 8:31 - Non-VC shaped business struggles 16:51 - Starting a new company 19:41 - From metrics to conversation stages 22:42 - Voice AI evolution 26:40 - Balancing determinism and freedom 29:53 - Who uses Canonical and when 32:39 - Don't make your agent spell anything 35:52 - Zero to 80% is easy, production is hard 39:28 - Future of voice AI adoption 42:21 - Book recommendations and closing This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit www.smartspeakers.fm [https://www.smartspeakers.fm?utm_medium=podcast&utm_campaign=CTA_1]

Olivia Moore, a16z: Voice as a wedge

Voice AI is having its moment, but pretty soon every company will be a voice company. Olivia Moore is the author of a16z’s market report on voice AI agents [https://a16z.com/ai-voice-agents-2025-update/], which is a must-read if you’re interested in the space. She’s an amazing thinker and we cover a lot in this conversation, including: * Olivia's thesis that Voice AI is in it’s “internet in 1999” moment * The "wedge" strategy: using Voice AI to get in the door before transforming broader business operations * How recruiting became a surprising early adopter of Voice AI (candidates actually prefer it) * Voice AI's unique ability to handle compliance and stay on-script in regulated industries * Shifting from per-minute pricing to transaction-based fees or success metrics * Why big tech platforms (OpenAI, Google) won't dominate vertical-specific voice applications Links * Olivia on X: https://x.com/omooretweets [https://x.com/omooretweets] (must-follow!) * Her market report on voice AI agents [https://a16z.com/ai-voice-agents-2025-update/] * Dr Sbaitso emulator [https://classicreload.com/dr-sbaitso.html] - this was packaged with new Sound Blaster sound cards! Strange stuff. Chapters0:00 Intro and welcome1:24 Olivia's first AI "aha" moments 3:42 Coolest non-voice AI tools6:29 How Olivia got into the Voice AI space10:03 From consumer to enterprise13:50 DMV-bot16:22 Voice AI as a wedge20:57 Traction in the voice market24:24 Voice AI for recruiting28:59 Why AI doesn't go off-script31:03 Better experiences for candidates and customers33:24 The future of call centers37:02 Bear cases for Voice AI41:25 Open problems44:29 Pricing47:12 Working with twin sister Justine50:11 Three things Olivia's excited about Subscribe and listen: https://smartspeakers.fm This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit www.smartspeakers.fm [https://www.smartspeakers.fm?utm_medium=podcast&utm_campaign=CTA_1]