Creator of @foldkit. Helping you ship better frontends faster with @EffectTS_.

United States
For the @reactjs folks eyeing @foldkit: think of it like an entire framework centered around the useReducer pattern.
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Another @foldkit Blocks + Effect Layers preview release shipped. Getting closer! This round includes: - Better Step inference and more consistent UI factories - Machine authoring that follows the same patterns as Blocks (super excited about this) - Query/KeyedQuery freshness, bounded caching, cancellation, and completion notifications (not specific to Blocks/Layers, but needed for something I’m working on and quite useful!) - VirtualList improvements (same deal as above) - Fixes for SSR dev reloads, SSG preview routing, Mount cleanup, and keyed Command cancellation Thank you to everyone testing and reporting issues. What changed, migration guides, and copyable agent prompts: github.com/foldkit/foldkit/p…
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Devin Jameson retweeted
Huge milestone for @alchemy_run. It's been so fun supporting this growing community and being a part of the @EffectTS_ wave of 2026.
this calls for a celebration 🥳 @alchemy_run has crossed a million downloads on npm
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Love @alchemy_run so bad. It feels like a cheat code.
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Hacking on something just for fun, will share soon ☕ This @foldkit Scene test covers these invariants: - Prices stay hidden until their domain checks complete - Top Results can be added to the cart while the remaining checks are pending - Later results appear without clearing the results already loaded Exercises the real update and view, with deterministic control over when requests complete. No browser, function mocks, or network interception.
fun fact, the most difficult frontend work i've ever done was the vercel domains search input naively it's a simple problem, but there's so much under the hood that goes into it
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Devin Jameson retweeted
If you're a developer, pay attention to what Sam says below. 👇 Coding agents are changing local and global maxima. In the extreme, frameworks & paradigms that were 'bad' before because 'boilerplate' / 'unfamiliar' can now dominate completely. Unlearn what you have learned.
Software is having its Industrial Revolution and it’s changing what matters in software frameworks. Today’s frameworks were designed for the crafty carpenter, tomorrow’s are designed for mass manufacturing processes where rigor > conciseness. Take foldkit vs react/solid, for example. You can argue that foldkit is more verbose or complicated for some use cases compared to the traditional alternatives, but everything doable in react/solid is also doable in foldkit. Everything doable in foldkit is not (or at least not easily or consistently) doable in react/solid because they lack the rigor of command+event state machines with story & scene testing. Getting that back isn’t easy and is a substantial loss for agentic coding. Before AI, there was the valid argument of picking what humans like best. Humans kinda suck at programming because we are constrained by our skills, taste and (lack of) discipline, so frameworks that worked in this era catered to the lowest common denominator of mass market human developers. While I agree that react/solid are powerful in the hands of humans, that simply doesn’t matter anymore. What’s best for humans does not necessarily translate to what’s best for agents. Some tasks may indeed be “a bit harder” with foldkit in human terms, but AI is capable of solving all of them in a few minutes, so who cares. Instead of bike-shedding philosophy and taste, just choose the more rigorous (and scalable) option. It costs you nothing and gains you everything. Effect is another example of this. With AI, now everyone of all skill levels can use advanced programming techniques that are objectively safer and more scalable, but were out of reach for many human programmers. Or didn’t appeal to the stubborn tastes of a particular person. With humans now out of the way of technology adoption - I think it’s obvious that the following techniques are going to become way more commonplace: 1. State Machines 2. Functional programming 3. Declarative infrastructure 4. Test Driven Development 5. Domain Driven Design 6. Actor Systems 7. Rigorous API schemas 8. Type Safety and Formal Verification 9. Disciplined Operations (monitoring, on-call) Alchemy is designed to bring these techniques together into a seamless experience for building and deploying applications of massive scale. It is the “rails” and “parts” of the ai software assembly line.
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Devin Jameson retweeted
Of course all built on durable objects, alchemy, foldkit, pi durable, and even effect-machine by @SandroMaglione They’re just such a powerful abstraction that even a fairly complex architectures are so easy to achieve And agents are so good at them
Agents playing monopoly Ok this might be the funnies thing i've done in a while
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Devin Jameson retweeted
galaxy brain: ban react
Debating just straight-up banning useState in my React apps Push the agent into the black hole of success
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Devin Jameson retweeted
Software is having its Industrial Revolution and it’s changing what matters in software frameworks. Today’s frameworks were designed for the crafty carpenter, tomorrow’s are designed for mass manufacturing processes where rigor > conciseness. Take foldkit vs react/solid, for example. You can argue that foldkit is more verbose or complicated for some use cases compared to the traditional alternatives, but everything doable in react/solid is also doable in foldkit. Everything doable in foldkit is not (or at least not easily or consistently) doable in react/solid because they lack the rigor of command+event state machines with story & scene testing. Getting that back isn’t easy and is a substantial loss for agentic coding. Before AI, there was the valid argument of picking what humans like best. Humans kinda suck at programming because we are constrained by our skills, taste and (lack of) discipline, so frameworks that worked in this era catered to the lowest common denominator of mass market human developers. While I agree that react/solid are powerful in the hands of humans, that simply doesn’t matter anymore. What’s best for humans does not necessarily translate to what’s best for agents. Some tasks may indeed be “a bit harder” with foldkit in human terms, but AI is capable of solving all of them in a few minutes, so who cares. Instead of bike-shedding philosophy and taste, just choose the more rigorous (and scalable) option. It costs you nothing and gains you everything. Effect is another example of this. With AI, now everyone of all skill levels can use advanced programming techniques that are objectively safer and more scalable, but were out of reach for many human programmers. Or didn’t appeal to the stubborn tastes of a particular person. With humans now out of the way of technology adoption - I think it’s obvious that the following techniques are going to become way more commonplace: 1. State Machines 2. Functional programming 3. Declarative infrastructure 4. Test Driven Development 5. Domain Driven Design 6. Actor Systems 7. Rigorous API schemas 8. Type Safety and Formal Verification 9. Disciplined Operations (monitoring, on-call) Alchemy is designed to bring these techniques together into a seamless experience for building and deploying applications of massive scale. It is the “rails” and “parts” of the ai software assembly line.
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Devin Jameson retweeted
🔥 𝗝𝗼𝗵𝗻 𝗗𝗲 𝗚𝗼𝗲𝘀. 𝗛𝗮𝗿𝗿𝘆 𝗦𝗼𝗹𝗼𝘃𝗮𝘆. 𝗗𝗲𝘃𝗶𝗻 𝗝𝗮𝗺𝗲𝘀𝗼𝗻. 𝗢𝗻𝗲 𝘀𝘁𝗮𝗴𝗲 𝗶𝗻 𝗠𝗶𝗮𝗺𝗶. Proud to announce the full lineup for 𝗘𝗳𝗳𝗲𝗰𝘁 𝗠𝗶𝗮𝗺𝗶 #𝟯! 🎤 @jdegoes · @ZivergeTech “Harnessing AI Models with Effect TS” 🎤 @harrysolovay · @crosshatchdev “Advanced Design Patterns with Effect” 🎤 @devinjameson · @foldkit “Foldkit: Frontend for Agents and Humans” Three brilliant engineers exploring what’s next in TypeScript, AI, and software architecture. Miami developers, CTOs, and engineering leaders, don’t miss this one! 📅 Nov 9 · 5:30 PM 📍 @thelabmiami · Wynwood 🤝 Organized by @SemantivAI 🎟️ luma.com/0yaas5h2 @EffectTS_ #EffectMiami #miamitech
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The latest @foldkit Blocks + Effect Layers preview is ready. Getting closer to being ready for main. The reduction in boilerplate and wiring compared to the stable API is pretty striking! Migration guides and copyable agent prompts in the linked PR. github.com/foldkit/foldkit/p…
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This preview release includes cleaner updates and Step helpers, more child Binding options, better testing helpers, and TypeScript/runtime performance improvements. Remaining limits are documented. Thank you to everyone testing the previews. Your feedback is driving this iterative process. ❤️
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Regarding boilerplate reduction, here’s the job application example’s complete update, with its local helpers inlined for this screenshot. Field changes, child Block operations, and Steps compose in one exhaustive handler record, with inferred Model, Message payloads, and Command requirements.
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Devin Jameson retweeted
Inspired by @foldkit's story testing - Alchemy Domain lets you do the same but for the backend. Test your service with the same language and mental model as you speak about it with your team.
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Devin Jameson retweeted
New: domain-driven design for Effect, in alchemy.run/domain. Translate business requirements directly into working software and integrate into your alchemy infrastructure.
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BLOCKS AND LAYERS
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