The Golden Age of Prototypes (and The Other 90%)
AI agents get you to 90% of a working product faster than ever - but the real challenge is the other 90%
AI coding agents have brought on the golden age of working prototypes. You can get from raw idea to 90% of a real working software product faster than we ever dreamed. It's amazing.
The challenge? The other 90%.
"The first 90 percent of the code accounts for the first 90 percent of the development time. The remaining 10 percent of the code accounts for the other 90 percent of the development time." - Tom Cargill, Bell Labs. (Programming Pearls, 1985)
Nineteen. Eighty. Five. My experience tells me this holds true 40 years later - maybe it's shifted with agents, but not that much.
Does this mean that AI driven prototypes are not valuable? Of course not.
It just means we need to spend just as much if not more of our energy figuring out how to apply our new magical tools to that other 90% just as well as we do to generating the code that gets us "almost there".
This is where I'm putting the lion's share of my focus these days.
Remember: "trust is earned in drops and lost in buckets."
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