Joined June 2012
- Tweets 19,875
- Following 489
- Followers 2,433
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430 Photos and videos
Colin O'Brien retweeted
Jun 12
While it's certainly possible Mythos could have found the same bugs if its operator invested more time and focus on HtmlSanitizer, most defenders don't have access to Mythos. I sure didn't.
To be terse: Less FOMO, more resourecefulness.
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shayon.dev/post/2026/161/bui…
Great blog post by @shayonj - a sneak peak into what we've been working on at Tines!
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Jun 13
FFmpeg is moving to Rust 🦀
Our use of C and Assembly in FFmpeg has been an unacceptable violation of safety.
FFmpeg will be running 10x slower - but we're doing it for your safety.
All your videos will appear green - safety first, working software later.
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Colin O'Brien retweeted
Jun 12
The fact that I can't touch my academic research from 18 years ago with Fable without triggering a model downgrade due to "cyber" is ... baffling.
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Jun 11
Fable won't help me write safer software because it flags that as a policy violation. This approach is going to be very bad for software quality.
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Jun 11
I'm just asking it to use `open_at` instead of `open` to ensure that I'm safe from various file-system mistakes. That is what is getting flagged. Asking it to use a safer API is causing Fable to think that I'm violating policy.
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Colin O'Brien retweeted
Jun 10
Cannot think of a more disastrous set of decisions to make ahead of an IPO, the reaction to data policies alone will show up in their revenue figures, to say nothing of cost control measures
SITUATION DETECTED: Microsoft is limiting internal employee use of Fable 5 over Anthropic's new data retention requirements, per The Verge.
Fable 5 requires data retention to operate its safety classifiers, unlike other Claude models which run under Zero Data Retention rules.
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Colin O'Brien retweeted
Jun 10
Thought I'd found a task that I could use Fable 5 for (porting a QEMU emulator to WASM). But nope, 1.5 hours into the session it tried to disassemble some code to figure out why it was hanging and silently downgraded to Opus 4.8 which has been producing shitty code ever since
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Colin O'Brien retweeted
Jun 10
I strongly recommend that you set this config option if you're trying to use Claude Code; automatically falling back to a model that's going to write worse code is an insane and unsafe behavior. But personally I do not plan to use Fable 5 until they fix their classifiers.
Jun 10
Thought I'd found a task that I could use Fable 5 for (porting a QEMU emulator to WASM). But nope, 1.5 hours into the session it tried to disassemble some code to figure out why it was hanging and silently downgraded to Opus 4.8 which has been producing shitty code ever since
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Colin O'Brien retweeted
Jun 10
When Fable is removed from Claude plans later this month I’m gonna have to backfill it by hiring an employee who creatively refuses to do their work.
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Fable is dead on arrival. I can't use it. I literally am just writing a library for filesystem capabilities and it refuses, it's not even close to malicious, it's not even like it's writing adversarial use cases.
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Fable is dead on arrival. I can't use it. I literally am just writing a library for filesystem capabilities and it refuses, it's not even close to malicious, it's not even like it's writing adversarial use cases.
This is dogshit.
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User: *breathes*
Claude: API Error: Claude Code is unable to respond to this request, which appears to violate our Usage Policy. Please double press esc to
edit your last message or start a new session for Claude Code to assist with a different task.
JUST IN: Anthropic will reportedly release its new AI model “Mythos” tomorrow.
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UUIDs have to be the most ironic performance footgun ever.
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Trading literally everything - locality, space, indexing, etc - just so that you can avoid a trivial DB operation that will scale trivially forever.
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Maybe I'll finally write a blog post about this but I think people don't realize how much they lose every time they choose UUID over an integer.
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Colin O'Brien retweeted
Jun 7
@thegrugq this is an obvious consequence of imposing rules about not reporting known breaches instead of imposing liability, period.
If companies don't want liability for data that leaks, they need to either ensure security, or not hold the data!
x.com/arekfurt/status/206337…
Quite a revelation this week.
In 2000, the former IBM VP of Threat Intelligence filed a lawsuit against IBM and AT&T essentially alleging IBM's poor security monitoring was intentional. To avoid understanding the scope of breaches and data exfiltration and having to report them.
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