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Andrew Clark
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@acdlite

Andrew Clark

@acdlite
@reactjs core team, @nextjs, @vercel. Hi!
Manhattan, NY
andrewclark.io
Joined February 2009
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  • Pinned
    @acdlite
    Andrew Clark
    @acdlite
    Dec 13, 2023
    One cool thing about working on a web framework is that the tools you use to build a feature might eventually adopt the feature itself. 5.5 years later, in this case.
    15
  • @acdlite
    Andrew Clark
    @acdlite
    Aug 12
    It’s also fun how these exact patterns emerge at every layer of the stack. My work is a zillion layers of abstraction removed from processor architecture but I deal in all the same things.
    @straceX
    Strace
    @straceX
    Aug 10
    computers are built on an absurd amount of cheating > caches > branch prediction > speculative execution > virtual memory > out of order execution and somehow the illusion holds
    4
  • @acdlite
    Andrew Clark
    @acdlite
    Aug 7
    What's great about writing tests with 𝚒𝚗𝚜𝚝𝚊𝚗𝚝() is that it eliminates races. It verifies the structure of your app (Is the page cacheable? Is there a sufficient loading skeleton?) independent of network conditions. But like a proper e2e test, it also doesn't rely on
    @nextjs
    Next.js
    Vercel
    @nextjs
    Aug 7
    Navigations in v0 got ~3.5× faster with Next.js 16.3. An agent ran this loop on each slow nav: 1. Write a failing 𝚒𝚗𝚜𝚝𝚊𝚗𝚝() test 2. Apply a fix from the Skill 3. Re-run the test 4. Repeat 2–3 until it passes nextjs.org/blog/making-v0…
  • @acdlite
    Andrew Clark
    @acdlite
    Aug 7
    "Turn all the navigations instant. Make no mistakes. Prevent future mistakes."
    @nextjs
    Next.js
    Vercel
    @nextjs
    Aug 7
    Navigations in v0 got ~3.5× faster with Next.js 16.3. An agent ran this loop on each slow nav: 1. Write a failing 𝚒𝚗𝚜𝚝𝚊𝚗𝚝() test 2. Apply a fix from the Skill 3. Re-run the test 4. Repeat 2–3 until it passes nextjs.org/blog/making-v0…
  • @acdlite
    Andrew Clark
    @acdlite
    Jul 22
    Thinking about this yet again.
    @acdlite
    Andrew Clark
    @acdlite
    Nov 21, 2023
    I wish every test runner had this built in: gate a test behind a flag, and assert it fails if the flag is off. I was unsure about it when I first added it to the React repo, but it's been a godsend (acdlite-send?) for iterating on experimental features github.com/facebook/react…
    1