Your LLM doesn't know what day it is: date handling for AI tool calls
If you're building AI features into your product, your model has no idea what day it is - and it will confidently guess. Here's how to fix it.
Mike Bifulco
Developer Advocate & Startup CTO
I work as a co-founder & CTO at Craftwork — I'm a founder & product builder with background in design and development.
Find me on Bluesky @mikebifulco.com, Threads @irreverentmike or Mastodon.
LATEST
Why your prompt cache hit rate is zero: the silent invalidators
Prompt caching is a prefix match: one changing byte near the top of your prompt drops your hit rate to zero. A timestamp is the obvious culprit - here are the rest.
The Strangler Fig Pattern: Rebuild Everything, without losing your mind
When your prototype becomes the product your business depends on, you can't just start over. Here's how the Strangler Fig pattern let us rebuild safely.
Cognitive Debt and the Cost of Staying Wrong
Being wrong is unavoidable. The real damage comes from allowing a bad assumption to shape everything you build on top of it.
You are not your user. Except when you are.
"You are not your user" is fundamentally good advice. It's also occasionally wrong, but in a very useful way.
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CSS Tips Part 2 - text-wrap: pretty will make your text feel intentional
Go beyond balance. Learn how text-wrap: pretty improves readability, reduces awkward breaks, and makes your UI feel more polished.
Dunning-Kruger for Vibe Coders
The first thing AI teaches you about coding is confidence. The second is why that's a problem. Let's talk about the Dunning-Kruger effect.
Lessons I Learned the Hard Way
Your brain rewires itself based on what you practice. If you stop practicing hard things, you slowly lose the ability to do them.
Learn to Love the Rebuild
Refactoring isn't a necessary evil -- it is the job. Why the best product teams rebuild constantly, at every scale.
Just Enough Is an Ongoing Practice
Stable products still need maintenance. Defaults and shiny features quietly tax systems over time, and efficiency is a sign of craftsmanship, not penny-pinching.
Optimizing Your Next.js Site's Fast Origin Transfer and ISR Reads
Next.js Link prefetching quietly burned through 15 GB of bandwidth on my Vercel-hosted blog. Here's how I fixed it.
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