Reflections on Clojure: Design, Simplicity, and Development Flow

Recently I have felt the urge to write something about Clojure, but an even stronger urge often appears: to rewrite my blog website using Clojure, which delayed this article. Now let’s talk about the Clojure programming language.

The first programming language I actually used was Ruby. I still use Ruby daily for client work, mostly Rails applications. I have done extensive prototyping with Ruby—a very elegant language, though it requires great self-discipline from programmers to avoid common pitfalls.

I have been following Clojure for a long time, reading books and watching videos, but mostly just dipping my toes. A few weeks ago I got an opportunity to write a small service program for a client in Clojure, which gave me a completely different experience. Since then I have felt that prototyping and programming in Clojure feels more natural and smooth. Below are my impressions and thoughts from developing with this language, and why Clojure has become my favorite and most-used programming language. Disclaimer: I am not a Clojure expert, and I cannot guarantee that everything I say is correct—these are merely my short‑term experiences from limited projects using this language.

Clojure gives a feeling of careful design

Coming from Ruby, this is the feature that shocked me most about Clojure. The language underwent two years of design before its release (even without any code produced, purely on paper). You can sense this from the very first encounter.

When using a programming language, I often encounter situations where I cannot understand why my code does not produce the expected output. When this happens, for example with JavaScript, finally figuring out what went wrong can be frustrating—most of the time when I ask a more experienced JS programmer for help, they say:

“Haha, of course that doesn’t work! Look here, in JavaScript this is a special case. You need to do it this way.”

This leaves me feeling annoyed. I cannot count this as learning knowledge; it’s just a workaround in that language. It doesn’t feel like real knowledge.

In Clojure, I usually realize that the mistake is mine (e.g., treating a lazy sequence as a regular one), and the language guides me to do things correctly. It feels as if I were asking Rich Hickey (the creator of Clojure), he would reply:

“Haha, this certainly doesn’t work! Think again—everything should operate the way it ought to. You used the wrong function, you used the wrong data structure.”

That is genuine knowledge, and it makes me happy.

Clojure is concise and elegant

Clojure is not a pure functional programming language, which makes it more approachable and easier to learn for most people. Nevertheless, it remains highly functional, giving the language elegance, simplicity, and power.

When programming in Clojure, I find myself first creating very small, reusable functions and then cleverly combining them to build larger programs. Its extremely simple module system makes it easy to clarify the modules of my program and their dependencies.

Moreover, whenever I notice an ugly interface or duplicated code, I immediately feel the need to think about it and refactor it; the language drives me to seek the best programming solution. This feeling is completely different from the struggle I used to have with other languages. It helps me achieve the simplest, most elegant programming strategy. For someone who has extensively used Ruby, C, and JavaScript, this is a completely new and exciting sensation.

The development process with Clojure is astonishing

In my experience, one of the most headache‑inducing aspects of programming work is wasting a lot of mental energy waiting repeatedly for program feedback. The Clojure development workflow solves this problem.

When programming with Clojure, your editor (Vim, Emacs, Light Table, …) stays continuously connected to the runtime environment. You get instant feedback on function development, testing, and modification. Your brain stays in a flow state while coding; slow feedback would interrupt logical thinking, which is unacceptable. This is also a major reason why I love Clojure.

So these are my current impressions of the Clojure programming language. If you haven’t tried it yet, I highly recommend you give it a go: visit the official website to see how to get started.