malli VS clojure-cli-config

Clojure's lazy sequences by default are wonderful ergonomically, but it provides many ways to use strict evaluation if you want to. They aren't really a hassle either. I've been doing Clojure for the last few years and have a few grievances, but overall it's the most coherent, well thought out language I've used and I can't recommend it enough.

There is the issue of startup time with the JVM, but you can also do AOT compilation now so that really isn't a problem. Here are some other cool projects to look at if you're interested:

Malli: https://github.com/metosin/malli

Babashka: https://github.com/babashka/babashka

Clerk: https://github.com/nextjournal/clerk

BREAKING: walking a :schema passes children instead of [id] to the walker function #884

When you get to larger, more complex validations, I'd recommend checking out Malli or Spec.

for specs, you can try malli - feels pretty well supported and full featured: https://github.com/metosin/malli (i'm not 100% sure how popular it is for others, but I use it on my personal projects)

Have you tried malli: Data-driven Schemas for Clojure/Script?

All that being said, I particularly use malli and I don't find anything to complain about. There is a very nice and sound ecosystem being built around it (malli-ts is one of my contributions to it, but still in early development stages). I highly recommend reading its README, very informative stuff.

Any large codebase can be broken up into small isolated components that can be reasoned about independently. This is how you structure Clojure projects if you want them to be maintainable. Clojure inherently encourages doing this by defaulting to immutability. The contract between components is the data being passed to the component and returned by it. Using Malli schemas at the edges of the components is a typical approach to documenting their APIs https://github.com/metosin/malli

I see the fact that people often end up creating large and tightly coupled monolithic codebases in static languages as a negative aspect of static typing. Such codebases are difficult to reason about even if you have guarantees that the types align. Ultimately, you need to understand the relationships in code, and how they relate to business logic. The more coupling an application has the harder it becomes to reason about it as a whole.

Ideally, I think applications should be structured as a bunch of Lego blocks that can be composed together. Each component should encapsulate some functionality, and then the flow of the business logic should bubble up to the top and expressed in how these components are chained together.

Uhhh spec has existed for a long time and before that, schema Nowadays we also have the excellent malli. If his codebase is full of functions where the shape of the data isn’t obvious, isn’t documented and isn’t specified in a specific/schema, that’s on him and his bad coding practices and really no different from passing data in other dynamic languages. A class by itself (without additional effort) only gives you field names.

Programming Clojure 3rd edition does have some minimal coverage of the CLI but it just barely made it to publication and a lot has been added since. You might find the CLI guide (https://clojure.org/guides/deps_and_cli) and CLI reference (https://clojure.org/reference/deps_and_cli) to be helpful for some questions. The Practicalli guide (https://practical.li/clojure/) has a number of good pages and resources on repl, tools, and use.

Yeah this is grim.

There is https://github.com/practicalli/clojure-deps-edn which solves this but it’s not linked to from any official docs which seems a miss to me. As well as the config and full documentation, it also comes with a video walking you through a demo of all the features.

I was lost when I moved to deps from lein, but just forking and cloning https://github.com/practicalli/clojure-deps-edn as $HOME/.clojure solved the problem - this base deps.edn contained all the aliases I needed - creating a new project, searching and adding dependencies, hooking up data inspectors like portal or reveal, testing, code coverage, benchmarking, building uberjar etc. Moving to deps also introduced me to polylith [1], which has been very useful for building large multi-component projects

[1] https://polylith.gitbook.io/polylith/

When I'm looking for tooling related stuff I do always check practical.li (https://practical.li/clojure/) since it probably has a good, if terse, description and mostly has links to the good documentation (or at least the best available).

4. You need build tooling and it seemed the choices were lein (easy user experience but not “blessed” future direction? - not sure about what i’m saying here but it’s the understanding i formed). Tools.deps is the blessed approach but designed to customise the heck out of it - problematic for a beginner like me! Thankfully you can park the customisation for later and just get started with a well laid out starter https://github.com/practicalli/clojure-deps-edn - there’s even a video walks you through its features, all the inspectors and visualisers are nice to know about but not needed yet on a beginner journey