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Stefan Penner Profile
Stefan Penner

@stefanpenner

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A mix of Mountain Sports and Programming Stuff. Canadian, living in the USofA

Salt Lake City
Joined March 2008
Don't wanna be here? Send us removal request.
@mitchellh
Mitchell Hashimoto
20 hours
@thdxr Getting an agent to write a failing test to reproduce a bug before writing the patch (or prompting it to ensure the tests fail without their changes) is also excellent. TDD LLM edition is good
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@stefanpenner
Stefan Penner
15 days
Treasure hunters
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@mitchellh
Mitchell Hashimoto
19 days
Ghostty is now a non-profit project, fiscally sponsored by Hack Club. https://t.co/pkgc4TxdQL I view terminals as critical infrastructure that should be stewarded by a mission-driven, non-commercial entity that prioritizes public benefit over profit. Ghostty is now that.
mitchellh.com
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@stefanpenner
Stefan Penner
22 days
TIL: https://t.co/W4401jEJW4 gives you hardware-backed SSH keys tied to your Mac’s Secure Enclave, unlocked with Touch ID and locked with the machine.
secretive.dev
Protect your SSH Keys using your Mac's Secure Enclave.
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@stefanpenner
Stefan Penner
25 days
Birds aren’t real
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@ID_AA_Carmack
John Carmack
25 days
@Scobleizer The claims (vague as they are) are implausible — bandwidth and computation in production models are such that 20x+ improvements and 99% energy savings are just not on the table. There are plenty of improvements available, but none that go that far. Rather than just dueling
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@stefanpenner
Stefan Penner
29 days
Today’s afternoon adventure
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@dhh
DHH
1 month
Bash is beautiful when you embrace its constraints. Here's a lovely little pattern for parsing cli flags.
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@stefanpenner
Stefan Penner
1 month
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@stefanpenner
Stefan Penner
2 months
Trick or Treat
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@stefanpenner
Stefan Penner
2 months
one does not simple "rename" an XCode project...
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@stefanpenner
Stefan Penner
2 months
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@stefanpenner
Stefan Penner
2 months
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@stefanpenner
Stefan Penner
2 months
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@stefanpenner
Stefan Penner
2 months
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@stefanpenner
Stefan Penner
3 months
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@cramforce
Malte Ubl
3 months
Since this went very viral: I'm not actually a super human coder. It's automation and the shades of green represent me actually doing work. I don't know why GitHub doesn't filter the automated actions for this graph. It clearly can distinguish them in the API/UI. Vercel uses a
@adriandlam_
Adrian
3 months
vercel cto btw how is this even possible @cramforce
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@mitchellh
Mitchell Hashimoto
3 months
@ray_at_work @xtbot To clarify this: the reality of almost all software that ends up making billions of dollars is that you take one "revolutionary" idea someone came up with 15 years ago, then just relentlessly iterate on it. There are only a handful of "sparks of genius" along the way.
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@mitchellh
Mitchell Hashimoto
3 months
Ghostty 1.2 is now out! macOS Tahoe support, command palette, graphical progress bars, custom cursor shaders, background images, quick terminal on Linux, global keybinds on Linux, localization to two dozen locales on Linux, and hundreds more changes.
Tweet card summary image
ghostty.org
Release notes for Ghostty 1.2.0, released on September 15, 2025.
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