Calva on Windows

Note

This loose guide is aimed to assist my coworkers in setting up Calva (and the clojure development environment) on Windows!

Adoptium

To install a JDK that doesn’t suck (if you don’t have a JDK already installed), go to https://adoptium.net/download to download & install Adoptium.

Important

Make sure you enable the option to set the JAVA_HOME variable in the installer!

Clojure

To install clojure and accompanying tools, we’ll use clj-msi, which itself uses deps.clj, which is a great rewrite of the official Clojure CLI Tools written in Bash (urgh!).

Simply download the latest .msi installer from the Release page and install the software.

Git

Both Calva, as well as Clojure expect Git for several operations.

The simplest way to install is by using

winget.exe install Git.Git

from a PowerShell prompt.

Go through the installation and restart any applications, as git needs to be in the $PATH and most programs only inherit the PATH environment variable at launch.

Proxy

If you are sitting behind a corporate proxy, you need to configure the proxy for Clojure (Maven to be exact) first. They both use the same centralized .\m2\settings.xml config file for that. Under Windows the config file should be (created) under

• For cmd.exe
  • %USERPROFILE%\.m2\settings.xml
• For PowerShell
  • $env:USERPROFILE\.m2\settings.xml
  • or simply ~\.m2\settings.xml

Populate the file with, or add merge with already present sections (the relevant lines have been highlighted):

~/.m2/settings.xml

<settings>
    <proxies>
        <proxy>
            <active>true</active>
            <host>proxy.domain.de</host>
            <port>8080</port>
        </proxy>
    </proxies>
</settings>

and you should be good to go.

Info

This is mainly for the clojure and deps.edn specific stuff to work. If you’re using Leiningen as your project’s dependency manager, you should make sure that the http_proxy and https_proxy environment variables are set to http://proxy.domain.de:port correctly (as per the official documentation).

New Project

deps-new

If you don’t already have a project setup, I’d recommend using deps-new, which setups a deps.edn project.

This should be installed as a tool, so execute

clojure -Ttools install-latest :lib io.github.seancorfield/deps-new :as new

Refer to the official README.md section for creating an application or a minimal scratch project.

Tip

If you’re unfamiliar with clojure, the application template is pretty convoluted. Instead I’d recommend to use the minimal scratch template while getting started.

Look inside src/scratch.clj for some hints on running your first commands.

Leiningen

Some claim the easier way to setup a project is to use Leiningen. Though most projects nowadays seem to transition to deps.edn, Leiningen is still viable for a lot of (especially simple projects).

It is noteworthy, though, that installation on Windows uses Chocolatey, so you’d need to install it, if not already present. If you have it available, install lein (using an admin PowerShell instance):

choco install lein

Visual Studio Code

Our editor will be Visual Studio Code (or VSCode). Download and install it.

Calva

Of course, we want a nice development environment for Clojure. This is why we’ll use Calva. It’s a very nice batteries-included framework for Clojure development within VSCode.

To install it:

1. Open VSCode
2. Go to File -> Preferences -> Extensions
3. Search for Calva
4. Select Calva: Clojure & ClojureScript
5. Click on Install

After that, simply open your project folder inside VSCode and Calva should automagically start everything, including clojure-lsp as the LSP server.