Dad Jokes & Python Developer Experience

"What do you call a Frenchman wearing sandals?"

"Philippe Flop." 🥁 👴 😆

Developer Experience, what does that even mean?

For me, a huge part is to quickly being able to write, try out and experiment with code. In Python, that could be about having the dependencies and paths already set up, to easily run snippets in a REPL or in the IDE, and without it crashing because of some missing dependencies or configs.

Testable code

When I develop a new feature, I usually want to run & evaluate the code very early in the process. Maybe I'm working on parsing something, transforming or filtering out data: that's when I want to evaluate the code, while writing and figuring out how to solve the actual problem. I do this to verify the output and get ideas about how to refactor the code. I practice a thing called REPL Driven Development, and have written about it before. The workflow is a form of TDD and the refactoring part comes natural with this kind of workflow.

Reusable & Composable code

Another important thing for me is to have already existing code nearby and available to use again. I usually think of Python code as building blocks, like LEGO, and try to have that in mind when writing new functions and adding features. I have learned that from functional programming and it is helping me to solve problems using a step-by-step approach.

With building blocks, code is composable and is ready for re-use from start.

"What did Yoda say when he saw himself in 4K?"

"HDMI." 🥁 👴 😆

Delay Design Decisions

I don't think it is that important to put code in the right place from start (such as what kind of service or app, domain, repo or a folder). At least it isn't as important as writing code that can easily be moved from one place to another. Very related to the building blocks & LEGO way, mentioned above. This approach will likely lead to less wasted time & less design-upfront planning. It is easier to figure it out the proper place to put the code eventually, while iterating and developing. In my opinion, it is perfectly alright to rename or move around code while developing. It shouldn't be a difficult thing to do that.

I usually like to dive into a feature and start coding, rather than starting off by deciding name of a repo, or what type of service the feature should exist in. These things can be left to decide later, when learning more about what to actually build.

"Where do dads store their dad jokes?"

"In the Dadabase." 🥁 👴 😆

A Developer Friendly Architecture

The Polylith Architecture targets all of these things. During the development you have all code available for experimentation and you compose already existing code with new when building features. All code in a Polylith workspace is referenced as bricks, and you use them just as when building something with LEGO. Pick the ones you need along with writing new ones, and combine them into features. A brick can be used in several apps, services or projects as it is called in Polylith.

During development, you have one single virtual environment, with all paths and dependencies already set up. You also have a separate section especially made for trying out and experimenting. It is very similar to the scratch files in PyCharm, but they are versioned and included in the repo. These ones are very useful for evaluating code.

You can immediately dive in to writing code and push the decision about deployment into the future if you like. Add the project to the Polylith workspace, using a simple command, when you are ready for it.

A Dad Joke microservice

To get some insights in how Polylith and the Python tooling changes the way you develop and improves the Developer Experience, I have recorded an improvised video with live coding. Phew, it is difficult to speak & code at the same time. 😅

In this video, I'm taking the first steps into developing some kind of Dad Joke Service and use the Development Environment of Polylith to figure out how to build it.

^{Top photo by Toa Heftiba on Unsplash}