Zach Koch (@zachk) 's Twitter Profile
Zach Koch

@zachk

cofounder & ceo @fixieai // making AIs communicate like humans with ultravox.ai // jack of some trades

ID: 10704

linkhttps://ultravox.ai calendar_today27-10-2006 00:32:35

3,3K Tweet

910 Followers

525 Following

Zach Koch (@zachk) 's Twitter Profile Photo

I loved The Wizard and the Prophet by 𝙲𝚑𝚊𝚛𝚕𝚎𝚜 𝙲. 𝙼𝚊𝚗𝚗, so you should read that and then also read his articles here. Related, Vaclav Smil's How the World Really Works is also worth reading and is related

Zach Koch (@zachk) 's Twitter Profile Photo

Definitely not obvious to me that LLMs are better at any of those tasks (coordination, prioritization, resource-allocation) than humans. I can see them getting better at coordination and resource allocation, but not "understanding what's important" (aka: prioritization).

Zach Koch (@zachk) 's Twitter Profile Photo

I feel like we're starting to collectively drown in AI-generated bullshit. I am deeply bullish on AI (I run an AI startup!), but man, between the BS sales emails, bot replies on X, auto-generated shorts/reels on IG/YT, it is harder than ever to find authenticity. What to do?

Zach Koch (@zachk) 's Twitter Profile Photo

It's no wonder that platforms like Lovable and Bolt.new are scaling ARR so fast. You get sucked in with an amazing rough concept very quickly (that doesn't work but looks close!) and then need to spend a ton of time + tokens to try and get it working fully.

kwindla (@kwindla) 's Twitter Profile Photo

Ultravox is an innovative open source LLM that processes speech directly without converting audio to text. Fusing audio understanding into the first stage of the LLM has a number of benefits, including improved inference latency. Cerebrium write-up and code repo:

Ultravox is an innovative open source LLM that processes speech directly without converting audio to text. Fusing audio understanding into the first stage of the LLM has a number of benefits, including improved inference latency.

Cerebrium write-up and code repo:
Zach Koch (@zachk) 's Twitter Profile Photo

Anyone building with LLMs knows that model performance degrades in a multi-turn conversation, but I haven't seen much formal analysis until now: arxiv.org/pdf/2505.06120 Great work from Philippe Laban et al in putting this together. Now to fix it...

Zach Koch (@zachk) 's Twitter Profile Photo

Prompt engineering is hard because good, clear writing is hard. Most people are bad at this, and it takes a lot of time & energy to be good at this.

Zach Koch (@zachk) 's Twitter Profile Photo

Has anyone had success with Llama 4 yet? It's increasingly looking like a pretty big disappointment, even when compared with Llama 3.3. (Ultravox's current prod model is 3.3, and we've done a LOT of work to make it usable. But Llama 4 is looking just unusable at this point)

Zach Koch (@zachk) 's Twitter Profile Photo

I may be dumb, but the NYT's request for OpenAI to to save all logs...makes sense? It's not as though one can simply open the model and say, "ah-ha! there's the copyright infringement!" Infringement only takes place at output time. To demonstrate that, you have to store output

Zach Koch (@zachk) 's Twitter Profile Photo

This is something we've been working on for a while! If you're building on Voice AI, reliable scaling is key. Unlike most voice platforms, we manage our own fleet of H100s optimized for one thing: real-time voice AI. For only $100/month, say goodbye to hard concurrency caps.

Zach Koch (@zachk) 's Twitter Profile Photo

I love Clerk, but they really need a solution for the BS gmail problem. This type of fraud feels fairly obvious? FWIW, these are people that are trying to abuse our 30-min of free talk time

I love <a href="/ClerkDev/">Clerk</a>, but they really need a solution for the BS gmail problem. This type of fraud feels fairly obvious?

FWIW, these are people that are trying to abuse our 30-min of free talk time