The Uncanny Valley of Python Tools: Why I Built a Native Mac Playground

#softwaredevelopment #macos #python #programming

Months ago, I needed to test a simple Python script for work.

It was a 10-line idea — just for some automation steps. I hadn’t written Python in a few years, so I was quite rusty.

I opened my terminal and typed python3. The default REPL opened. It’s fine for 1+1, but try pasting a multi-line function or editing a loop, and it becomes a nightmare of indentation errors.

So, I opened VS Code. I waited for it to load. I created a new file: test.py. I saved it to my desktop (because you have to save before you run). Then the "Python Extension" started loading. Then it asked me to select an Interpreter. Then it asked if I wanted to create a Virtual Environment (venv).

I just wanted to test 10 lines of code.

This is the Uncanny Valley of Python Tools.

On one side, you have the Terminal : Instant, but dumb.
On the other side, you have the IDE : Powerful, but heavy.
In the middle? There is… nothing really worked for me.

Sure, there are web playgrounds, but they are slow, disconnected from your local files.

I realized I spent more time managing my environment than actually writing the code.

Scratching My Own Itch

I built CoilPad primarily for myself. I wanted a safe place to make mistakes and test ideas without the overhead of a “Real IDE.”

After using it for a few weeks, I realized other devs might share this same frustration, so I decided to polish it up and release it.

What it actually is

CoilPad is a native macOS playground designed to fill that gap. It is built for the moment you have an idea and just want to code, not configure.

It sits right in the “Goldilocks zone”:

Instant Start: It launches as fast as a text editor. No project files, no “folders,” no “indexing.”
Persistent Memory: Unlike the terminal, it remembers your variables. You can run x = 5, tweak your function, run it again, and x is still 5.
Local & Private: Your code runs on your machine, not in a browser.

Solving the “Rusty Syntax” Problem

Since I built this because I was rusty, I added the one feature I wish I had from the start: a Learning Center.

I didn’t want to Google “Python list comprehension syntax” for the 100th time. So I built a library of 40+ interactive topics directly into the app — from “Hello World” to “Async/Await.”

You can click a topic, see the code, and run it immediately to see what happens. It’s not just documentation; it’s a live playground.

Under the Hood

For the curious: I built this using Electron for the frontend (leveraging the Monaco Editor — the same engine that powers VS Code) but connected it to a persistent, native Python shell in the backend.

This gives you the best of both worlds:

The Experience: Syntax highlighting, autocomplete, and a beautiful UI.
The Power: Full access to your local machine (read/write files) and standard Python libraries.

A Request for Feedback

I’m just one developer, not a big company, so I’m sure there are edge cases I haven’t found yet.

If you’ve ever felt like firing up VS Code was overkill for a simple script, I’d love for you to give CoilPad a try.

I’m actively building this, so I’d genuinely appreciate your feedback — whether it’s a feature request or just pointing out a bug. I want to make this the best possible tool for us “rusty” Python devs.