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Michael Arnaldi
16.2K posts
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Michael Arnaldi
@MichaelArnaldi
BDFL @EffectTS_, CEO @EffectfulTech, Co-Founder @matechsdigital.
London
mike.tech
Joined December 2012
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@MichaelArnaldi

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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Jul 30, 2024
    Replying to @mattpocockuk
    1 will create a memory leak because you're returning the result of the subsequent calls recursively, will keep allocating closures that are never cleaned up
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    Michael Arnaldi
    @MichaelArnaldi
    Jul 16, 2025
    Replying to @theo
    You're absolutely right! I apologize I should rollback the last changes I made, they are very dumb and I was changing something that already worked
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Oct 11, 2025
    You should never ever use Effect! And more importantly you should never ever use Effect in the FrontEnd!
    user avatar
    Kit Langton
    Anomaly
    @kitlangton
    Oct 11, 2025
    Visual Effect is now Open Source 🫡
    00:00
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Sep 25, 2025
    I am here to tell you again to stop using Effect!!!
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Jun 21, 2025
    So owning on my side, I was triggered by this post and reacted in the wrong way. That's on me and a known issue I have been working to avoid. Apologies for that.
    user avatar
    Theo - t3.gg
    @theo
    Jun 20, 2025
    I thought Effect was supposed to prevent errors? Why is it breaking T3 Chat? 🙃
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Apr 24, 2024
    took 3 years of attempts but looks like we were finally able to kill the need to use an adapter function and we can just yield* effects! PR: github.com/Effect-TS/effe…
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Aug 12, 2025
    Stop downloading @EffectTS_ you sick people
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Sep 14, 2025
    Hot take: The Actor Model is the Right Primitive for Agentic Behaviour, not Workflows. No I won't go into details just yet.
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    Michael Arnaldi
    @MichaelArnaldi
    Sep 22, 2025
    What building Effect 4 is teaching us is that code simplicity almost always leads to better perf.
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    Tim Smart
    @tim_smart
    Sep 22, 2025
    When you speed something up by 100x, you often wonder if it's actually working lol.
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Aug 17, 2024
    Blogged about the mental model of Effect and how it maps to React. If you know React and are curious about Effect this should be a good read:
    From React to Effect
    From effect.website
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Jun 21, 2025
    Please don't turn this into a dig to Next & Vercel, comments are already wild. If you are a developer you shipped bugs, period, be empathetic towards other developers.
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    Sebastian Lorenz
    @thefubhy
    Jun 21, 2025
    As it turns out this is a bug in Next.js production builds.
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    Michael Arnaldi
    @MichaelArnaldi
    Jul 31, 2025
    should I stream wrapping the Vercel AI SDK with Effect for fun?
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Aug 14, 2025
    Show me a piece of code that includes telemetry, metrics, graceful shutdown, bounded concurrency, selective error retries with capped exponential backoff and that is testable and easily composable with the rest of your code and I will agree that Effect is not needed.
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  • user avatar
    Michael Arnaldi
    @MichaelArnaldi
    Jun 21, 2025
    Replying to @MichaelArnaldi
    I am not gonna delete my replies because I don't really want to hide the history. I have been fighting burnout from open source entitlement for a long time and I perceived this post as such even though it was instead a frustration tweet.
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