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Every blog post that took off on Hacker News, ranked by the votes of its best submission. 21,833 posts.

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10475

2FA on the command line

OTP: One-Time Password TOTP: Time-based One-time Password algorithm 2FA: Two-factor authentication There is no shortage of OTP 2FA apps availiable for your phone, such as Google Authenticator or Duo Mobile. These apps take an initial secret code, and create a TOTP anytime you need a 2FA code for login.… …

10483

The RubyGems "Security Incident"

Ruby Central posted an extremely concerning “Incident Response Timeline” today, in which they make a number of exaggerated or purely misleading claims. Here’s my effort to set the record straight. First, and most importantly: I was a primary operator of RubyGems.org, securely and successfully, for over ten years. Ruby…

10484

Magic Numbers

1500 bytes is a bit out there as numbers go, or at least it seems that way if you touch computers for a living. It’s not a power of two or anywhere close, it’s suspiciously base-ten-round, and computers don’t care all that much about base ten, so how did we get here?

10485

Citations on the Anthropic API

Claude can now cite specific passages from your documents, delivering verifiable responses with built-in source tracking. Update: Now available in Amazon Bedrock. (June 30, 2025) Today, we're launching Citations, a new API feature that lets Claude ground its answers in source documents.

10489

Will It Optimize? (2010)

See how well you know (or can anticipate) gcc's optimizer. For each question, the left box contains some code, while the right box contains code that purports to do the same thing, but that illustrates a particular optimization. Will gcc apply that optimization? Put another way, will the code on the left be as fast as…