Apple's sentiment analysis thinks 'delete the temp file' is a death threat

NLTagger is Apple’s API for sentiment analysis. It’s integrated into iOS and macOS, runs on-device, needs no server, and is three lines of code away. It’s the first thing you find when searching for “sentiment analysis Swift”. Here’s what it returns for text any developer would write on a normal day: Message NLTagger Reality “delete the temp file” -0.8 Neutral instruction “ok” -0.8 Neutral confirmation “run make test” -0.6 Neutral instruction “commit and push” -0.4 Neutral instruction “great job, thanks!” +1.0 Positive (correct) “this is fucking broken” -1.0 Negative (correct) The scale goes from -1.0 (very negative) to +1.0 (very positive). According to Apple, “delete the temp file” carries almost the same emotional weight as “this is fucking broken”. And “ok” – the most neutral response in the English language – scores -0.8. ...

April 5, 2026 · Fernando

TurboQuant, one month later: implementations, controversy, and what actually works

Google published TurboQuant on March 24th. Within 48 hours the paper had 575 points on Hacker News, Micron’s stock dropped $900 million, and TechCrunch compared it to Pied Piper’s algorithm from Silicon Valley. One month later, the hype fog has cleared enough to answer the only questions that matter: Does it work? Can I use it today? And the one nobody wants to ask: Is it actually new? What TurboQuant promises (30-second recap) If you already read my previous article on the math, skip this section. ...

April 5, 2026 · Fernando

NLTagger and Sentiment Analysis: Why Apple Thinks Your Code is Depressing

Imagine you’re building an app that analyzes conversations within a development team. You want to detect whether the team’s tone is healthy or if there are signs of stress. You decide to use Apple’s NLTagger because it’s readily available, free, runs on-device, and doesn’t require a server. Three lines of code, and off you go. First surprise: the phrase “kill the process and restart the daemon” scores -0.6. Negative. Almost hostile. “Fatal error in memory allocation” gets a -0.8. And “crash report uploaded successfully” — which is literally good news — scores -0.4. ...

March 28, 2026 · Fernando

Transform and Conquer: How Google Compresses LLMs 6x by Changing Coordinates

Multiplication is hard. Addition is easy. Any elementary school kid knows this. What they don’t know is that logarithms exist precisely to exploit this asymmetry: you convert multiplication into addition, operate in the simple world, then undo the transformation. The result is correct. The effort, a fraction. This pattern — transform the problem to a space where solving it is trivial, solve it, then transform back — is one of the most powerful in all of engineering. FFT does this with signals. Logarithms do it with products. And now Google just published a paper that does it with language model compression. ...

March 25, 2026 · Fernando

A 2,500-Layer Neural Network That Turned Out to Be MD5: What This Teaches About Debugging

Jane Street, one of the world’s most selective quantitative trading firms, published a mechanistic interpretability puzzle a few weeks ago. They hand-crafted a neural network with approximately 2,500 linear layers, integer weights, and released it to the public with a question: What function does this network compute? The answer: MD5. A cryptographic hash algorithm from 1992, implemented entirely as matrix multiplications and ReLU functions. What matters isn’t the answer. It’s the path the winner took to reach it. Because that path is, without exaggeration, a manual for debugging opaque systems that applies far beyond machine learning. ...

March 11, 2026 · Fernando