publish an article on downgrading Homebrew kegs

src/posts/homebrew.md

@@ -0,0 +1,49 @@
+---
+title: "Install a previous version of a Homebrew keg"
+date: "2024-12-12"
+tags:
+  - "Homebrew"
+image: "pexels-nextvoyage-3779784.jpg"
+slug: "homebrew"
+---
+
+You just upgraded to the latest version of a software that is critical to you, and there is a new bug that is causing you problems. It's software, it happens... You cannot wait for a fix to be released, so the easiest step would be to downgrade to the previous version which was working perfectly. Unfortunately if you installed it using [Homebrew](https://github.com/Homebrew/brew), unless the maintainers release different [versions](https://docs.brew.sh/Versions), which is rarely the case, there is no built-in way to do that. There is still a method for you to _easily_ do this. Let's try it with [Kubefirst](https://konstruct.io/kubefirst).
+
+First, find the file defining the keg that is used for the formula or cask you want to downgrade:
+
+```shell
+brew info kubefirst
+```
+
+The output will look like this
+
+![Output of Homebrew info command](../images/homebrew-screenshot-01.png)
+
+You can find the keg file used to install it listed next to the `From:` label: <https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/k/kubefirst.rb>
+
+Open the file in your browser, check the Git history, and open the commit for the version you want to install, in my case, 2.7.7. Click on the `View code at this point` icon which brings you to <https://github.com/Homebrew/homebrew-core/blob/3547be4a29b9e2a5cf1ccb8d624d81f7a4403cf8/Formula/k/kubefirst.rb>, and click the `Raw` button to get the absolute URL for the file itself. Now download a copy of the file locally:
+
+```shell
+curl https://raw.githubusercontent.com/Homebrew/homebrew-core/3547be4a29b9e2a5cf1ccb8d624d81f7a4403cf8/Formula/k/kubefirst.rb > kubefirst.rb
+```
+
+Before installing the desired version, uninstall the unwanted one:
+
+```shell
+brew uninstall kubefirst
+```
+
+Now you can proceed, and install the version you wanted directly from the file you downloaded:
+
+```shell
+# Use --cask if it's a Cask
+brew install --formula kubefirst.rb
+```
+
+The `--formula` flag is optional, but if not used, Homebrew will complain, but it will still work. Once you ran the previous command, you successfully downgraded Kubefirst from 2.7.8 to 2.7.7.
+
+![Output of kubefirst version command](../images/homebrew-screenshot-02.png)
+
+There may be simpler ways to install specific versions of any Homebrew kegs, but this is the easiest I came up with.
+
+_Photo by Nextvoyage_