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I Made My Python App Start 5× Faster without changing the code — Here’s How
Lazy Imports done right 💤
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Have you ever built a Python project that started snappy but turned into a sluggish beast over time? That was me with my Jupyter Notebook CLI. It started lean, but as I kept adding features and dependencies, the startup time slowed to a crawl — taking seconds to launch.
Frustrated, I went on a mission to fix it. Enter lazy imports: a simple yet powerful trick to load only what’s needed, when it’s needed. Suddenly, my app stopped dragging in unnecessary dependencies just to print the notebook to the screen. The result? A startup time under 500 milliseconds!
In this article, I’ll show you:
- Why lazy imports can supercharge your Python apps
- How to manually implement them
- How to use Python’s native lazy imports (without breaking your IDE’s autocompletion)
By the end, your Python app will be faster than ever. Let’s dive in!
By the way, if you are curious about the CLI app, you can read about it here: