ChatGPT's Codex: Here's What Makes It So Impressive. It's Changing the Future of Code Generation

Even if you’re not familiar with programming, you can write a fair amount of code using ChatGPT.
It’s been a long time since I was skeptical when I first heard that.

Especially since 2024, ChatGPT’s Codex feature has been enhanced, and it now works just like a “code craftsman.”
Here are a few examples of Codex’s amazing capabilities that I’ve come to appreciate through my daily coding.

It Does More Than Just Write Code

It goes beyond mere “code autocompletion” to enable the following:

• Just ask, “Write this feature in React,” and it suggests everything from file structure to components
• If you tell it “I’m getting an error,” it simultaneously suggests a fix for the relevant section and explains the cause
• It also carefully assists with “mundane but important” tasks like type definitions and validation

In other words, it writes, organizes, and fixes for you.
It’s just like having an excellent pair-programming partner.

Situations Where It’s Especially Helpful

• Integration with Next.js and Firebase: It accurately points out the location of code and dependencies
• Building blogs and apps: It suggests optimizations for directory structure and SEO-friendly code
• Error handling: Its ability to articulate and explain the root cause of bugs is especially reassuring for self-taught developers

Recommended usage tips based on my experience

1. Explicitly ask it to “write the complete code”
   → Asking it to write the entire code rather than just the differences reduces confusion

2. Specify file paths and exact locations
   → Simply telling it where to write the code results in more accurate output

3. Ask based on “what you want to do” rather than grammar or syntax
   → Asking based on “I want to do this” makes it more likely the output will match your intent

Conclusion: We’ve Moved Beyond “Writing” to an Era of “Guiding”

The emergence of Codex is changing the meaning of programming—shifting from an era where “people who can code” were valued to one where “people who can clearly communicate their ideas” hold value.

Anyone can build an app—as long as they have an idea.
We may already be beginning to embrace that future.