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bcherny

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github.com 7mo ago

We've rewritten Claude Code's terminal rendering to reduce flickering by 85%

bcherny
3pts3
www.anthropic.com 1y ago

Claude 3.5 Haiku

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2pts0
borischerny.com 2y ago

NPM and NodeJS should do more to make ES Modules easy to use

bcherny
233pts218
borischerny.com 2y ago

ES Modules Are a Mess

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2pts0
gist.github.com 2y ago

Designing-data-intensive-application-notes.md

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14pts0
borischerny.com 2y ago

Learning to work (very) remotely

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3pts2
borischerny.com 2y ago

Learning to Work (very) Remotely

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3pts0
news.ycombinator.com 2y ago

Ask HN: What app do you use for book recommendations?

bcherny
7pts7
engineering.fb.com 2y ago

Threads: Meta’s Newest Social App

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1pts0
news.ycombinator.com 2y ago

Ask HN: Why can't you unsubscribe from Apple promotional emails?

bcherny
18pts19
news.ycombinator.com 3y ago

Ask HN: Has anyone hacked together their own ground-penetrating radar?

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5pts2
borischerny.com 3y ago

Time, Timing

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1pts0
borischerny.com 3y ago

Time and Timing

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1pts0
borischerny.com 4y ago

Dinosaur food: 100M year old foods we still eat today

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135pts106
borischerny.com 4y ago

Dinosaur Food: the oldest plants we still eat today

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3pts0
en.wikipedia.org 4y ago

Gävle Goat

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1pts0
www.pnas.org 4y ago

Kinematic self-replication in reconfigurable organisms

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2pts0
www.pnas.org 4y ago

Kinematic self-replication in reconfigurable organisms

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3pts0
performancejs.com 5y ago

Data fetching on the web still sucks

bcherny
155pts96
news.ycombinator.com 5y ago

Ask HN: technical book club recommendations?

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2pts2
performancejs.com 5y ago

Public Opinion

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1pts0
chodenames.com 6y ago

Show HN: My friend built a Codenames clone

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3pts1
www.amazon.com 6y ago

Programming TypeScript: Making Your JavaScript Applications Scale

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5pts0
programmingtypescriptbook.com 6y ago

Programming TypeScript (2019)

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2pts0
programmingtypescriptbook.com 6y ago

Programming TypeScript (2019)

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2pts0
smile.amazon.com 7y ago

Programming TypeScript

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3pts0
performancejs.com 7y ago

Tips for Writing a Technical Book

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300pts67
performancejs.com 7y ago

13 Tips for Writing a Technical Book

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2pts0
performancejs.com 7y ago

Tips for Writing a Technical Book (from an O'Reilly Author)

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4pts0
undux.org 7y ago

State Management with React Hooks

bcherny
1pts0

For those using Claude Code, I recommend Learning mode to instruct Claude to walk you through implementing the solution yourself rather than doing it for you. It’s very helpful when diving into a new domain, and helps build lower level intuition.

To enable it, run /config > output styles > Learning

Yes, it also helps! That's a place where raw model capability is the most helpful, but we do find that some dynamic workflow configurations can be helpful too.

There's two main differences:

1. Support for 1-2 OOMs more agents, to do more work in parallel

2. A phased, semi-structured approach where work happens in steps

Hey, yep. A few things I personally used dynamic workflows for over the last few weeks:

1. Autonomously landed 20+ optimizations to reduce Claude Code's token usage by ~15%

2. Ported tree-sitter, color-diff, yoga-layout, and a number of other WASM and Rust native modules to TypeScript, improving CPU and memory use by 2-10x in the process

3. Made our CI faster, and repeatedly found and fixed flaky tests (with /loop)

4. Migrated from regex-based bash static analysis to tree-sitter, reducing false positive permission prompts by 45%

5. Reduced Claude Agent SDK startup time by 61%, by repeatedly profiling and optimizing the startup path, putting up a number of PRs in the process

6. Shipped 69 code simplification PRs, deleting >10k lines of code

A few of us from the Claude Code team will be hanging around if anyone has questions! Very excited for this launch -- dynamic workflows have been a game changer for engineering here at Anthropic. Can't wait to hear what you think.

Hey, Boris from the CC team here. I agree, we're working on consolidating these. Going forward it will just be the built-in /code-review skill.

Here's how to use the skill on the latest version:

/code-review # do a balanced code review. checks for bugs and inconsistencies, poor code quality, duplication, band aids, etc.

/code-review --fix # same as above, but also fix the issues

# choose an explicit effort level (defaults to your current effort level). all of these also accept --fix:

/code-review low

/code-review medium

/code-review high

/code-review xhigh

/code-review max

# do an expensive and extremely thorough review (reliably catches >99% of bugs, costs $3-20 per review depending on complexity):

/code-review ultra

Open to feedback if anyone has feedback or ideas for how to make these even nicer to use.

Hey, Boris from the team here.

We did both -- we did a number of UI iterations (eg. improving thinking loading states, making it more clear how many tokens are being downloaded, etc.). But we also reduced the default effort level after evals and dogfooding. The latter was not the right decision, so we rolled it back after finding that UX iterations were insufficient (people didn't understand to use /effort to increase intelligence, and often stuck with the default -- we should have anticipated this).

Hey, Boris from the Claude Code team here.

Normally, when you have a conversation with Claude Code, if your convo has N messages, then (N-1) messages hit prompt cache -- everything but the latest message.

The challenge is: when you let a session idle for >1 hour, when you come back to it and send a prompt, it will be a full cache miss, all N messages. We noticed that this corner case led to outsized token costs for users. In an extreme case, if you had 900k tokens in your context window, then idled for an hour, then sent a message, that would be >900k tokens written to cache all at once, which would eat up a significant % of your rate limits, especially for Pro users.

We tried a few different approaches to improve this UX:

1. Educating users on X/social

2. Adding an in-product tip to recommend running /clear when re-visiting old conversations (we shipped a few iterations of this)

3. Eliding parts of the context after idle: old tool results, old messages, thinking. Of these, thinking performed the best, and when we shipped it, that's when we unintentionally introduced the bug in the blog post.

Hope this is helpful. Happy to answer any questions if you have.

Hey, Boris from the Claude Code team here. People were getting extra cyber warnings when using old versions of Claude Code with Opus 4.7. To fix it, just run claude update to make sure you're on the latest.

Under the hood, what was happening is that older models needed reminders, while 4.7 no longer needs it. When we showed these reminders to 4.7 it tended to over-fixate on them. The fix was to stop adding cyber reminders.

More here: https://x.com/ClaudeDevs/status/2045238786339299431

There were two issues with some other 3p harnesses:

1. Poor cache utilization. I put up a few PRs to fix these in OpenClaw, but the problem is their users update to new versions very slowly, so the vast majority of requests continued to use cache inefficiently.

2. Spiky traffic. A number of these harnesses use un-jittered cron, straining services due to weird traffic shape. Same problem -- it's patched, but users upgrade slowly.

We tried to fix these, but in the end, it's not something we can directly influence on users' behalf, and there will likely be more similar issues in the future. If people want to use these they are welcome to, but subscriptions clients need to be more efficient than that.