designing interfaces for humans and agents @fastreplinc | yc alum

Seoul & SF
Joined November 2021
had a dinner with this guy in korea heard that he writes code seems cool
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i forgot to tell @s_II_a about my flight back to seoul, but @getcharnotes reminded me of this! (defcon is our daily standup meeting)
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alright game on. bro's getting a legal notice.
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bro tried to copy @anarlogapp but his agent turned him in to us lol
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private beta is now resumed
preview of our meeting notetaker feature
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John Jeong retweeted
As a builder in the AI video space, I was terrified about how much markup API providers charge for simply routing the models. Higgsfield API adds a 40% markup even with its maximum advertised discount. Fal adds 100%. Runway adds 414% (Seedance 2 480p) I might be hated by the industry, but : 
 Today, we’re launching Sume API, the first image & video model provider with 0% markup. For example with Seedance 2.5 1080p • 50% cheaper than fal • 50% cheaper than higgsfield api (29% even with biggest discount) • 28.02% cheaper than kie ai The routing infrastructure layer is never the moat. We believe that APIs should be commoditized, and the moats will be built at the application layer. Check the pricing comparisons below, and see how the broken industry is saved.
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bro just stop spinning
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i've officially started using dark mode
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thanos vs theranos
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used our existing { } logo to create a connecting state animation
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i genuinely think anime is the best way to learn stuff. absolute cinema.
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huge. wtf is this giant leap? (rip tauri)
Cap v0.6.1 is here. Our engine was always Rust. Now the UI is too, rebuilt on GPUI with no web view. It's much faster. Memory: 3.7 GB → 440 MB CPU: 77% → 18% Exports: up to 5x faster 180+ fixes and improvements from 41 contributors.
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feel like there's less and less reason to start using notion as people will share more of their work as claude artifacts and things like that. if notion is already your company's knowledge base, staying makes sense. there's a switching cost. but i don't think that cost will stay very high. getting your knowledge out and making it useful somewhere else keeps getting easier. hmm... would love to hear other perspectives.
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are you ready for char?
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i want to ask all the fusion reactor startups, how do you prove that you're not a scam? my smartest friends working on fusion tell me that they can create an avg energy of a cheetos these days. are we actually getting anywhere? it's been a while since i got out of nuclear but man fusion was getting nowhere.
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we aren't using this in @getcharnotes anymore, but it's one of the concepts @s_II_a and i explored together. this one was inspired by a six-shot revolver. i liked the constraint: with only six rounds, you have to prioritize your targets. i thought the same constraint could work for surfacing information. you have to decide what's relevant enough to show, and what to leave out so you don't overwhelm the user. instead of another tab full of information, we explored a rotating cylinder with just six slots.
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billing per successful request is unreal! it makes me wonder why hasn’t this been the norm already
Replying to @deepseek_ai
🔍 Search & Fetch APIs are now open to everyone! Powered by our in-house search engine, serving hundreds of millions of requests daily worldwide. 💰 Each endpoint: $0.75 per 1,000 calls. 📖 Docs: api-docs.deepseek.com/guides… 📌 Search & Fetch calls via server-side tools in DeepSeek Harness, Claude Code, and Codex are currently free for DeepSeek API users. Billing starts Oct 31, 2026, at 16:00 UTC. 3/4
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ai can make a perfectly good song. but that’s exactly the problem. been listening to a lot of ai-generated music lately, and noticed something interesting. songs originally written by humans and then rearranged or covered using ai tend to sound way better than songs generated entirely by ai from scratch. i think it’s because human-made music has some kind of tacit knowledge baked into it. an intuition for what melodies resonate with people, what makes something catchy, and what actually moves you. when ai creates music from scratch, it feels like it’s producing the average of all the good songs out there. technically impressive, polished, and pleasant to listen to. but rarely something that gives you goosebumps or gets stuck in your head. maybe ai is great at making good things better, but still struggles to figure out what makes something great in the first place.
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