I Used Python for Everything — Until I Discovered Rust

For the longest time, Python was all I needed. It was simple. Fast to write. Easy to debug. From web apps to automation scripts — I built everything with it. But that changed one weekend.

It started when I was working on a project that processed massive CSV files — like gigabytes of them. My Python script took forever to finish. I tried everything — optimizing loops, using generators, even switching to Pandas. Still, it felt slow. So I did what any frustrated developer would do. I searched: “Why is my Python code slow?” That’s when I stumbled upon Rust. I didn’t know much about it, but every developer seemed to talk about speed, memory safety, and control. Honestly, I thought it was just hype.

1. My First Rust Experiment I decided to rewrite a small part of my Python script in Rust. Just a simple function that reads a CSV file and counts unique values. In Python, that part took almost 20 seconds. In Rust, after I figured out how to even compile the code, it took less than 2. That moment changed everything for me. But let me tell you — Rust is not like Python. In Python, I can just write something like this: data = set() for line in open('data.csv'):

   data.add(line.strip())

print(len(data)) In Rust, I had to declare types, manage errors, handle borrowing, and think about memory. It was frustrating at first. My code didn’t even compile the first five times. But once it ran, it felt powerful. Rust forces you to think differently. It makes you reason about what your code is doing — not just what you want it to do.

2. Where Rust Completely Blew My Mind After that first test, I got curious. What if I used Rust for something more real? I was building a Python API using FastAPI at that time. One part of it handled image uploads, resized them, and stored them on AWS. That part was painfully slow — especially when hundreds of images came in at once. So I tried rewriting only the image-processing part in Rust. It wasn’t easy, but the result shocked me. The Rust version ran almost 10x faster. And it used less memory too. But the best part… It never crashed. With Python, sometimes memory errors appeared randomly after long runs. In Rust, the compiler made sure everything was safe — before I even ran it. That gave me so much confidence in the code.

3. Where Python Still Wins Don’t get me wrong — I didn’t quit Python. Python is still my go-to for automation, AI, and quick experiments. I can build an idea in Python in minutes. Rust… That takes hours. But Python hides many things behind the scenes. Rust shows you everything — the memory, the ownership, the lifetimes. It’s like learning to drive a manual car after years of using automatic. In Python, you just write and run. In Rust, you have to think. And that thinking made me a better developer. Even when I went back to Python, I started writing cleaner, safer code. I now understand what’s happening in memory, and why certain bugs exist.

4. The Moment I Knew I Needed Both After a few months, I realized something important. It’s not about choosing between Python or Rust. It’s about knowing when to use which. For example:

When I need to build something fast, I go with Python.
When I need speed and safety, I write that part in Rust and connect it with Python using FFI or a library like PyO3.

That combination feels unbeatable.

I used to believe one language could do everything. But after using Rust, I understood that every language has a purpose. Python gives you freedom. Rust gives you control. And when you learn both — you stop coding blindly. You start understanding what’s really happening behind the screen.