I upgraded to Catalina, with Homebrew & Ruby, and this is how I did it flawlessly.


If you don’t already have homebrew installed, do that first. Install all Software Updates available in the Apple Menu, up to and including Catalina.


Haven’t had any hardware issues yet.


In order…


The upgrade will erase your previous XCode install.

(Optional) (re)Install XCode from the App Store first. The XCode Command Line Tools will actually install fine even without XCode.

After Xcode is finished installing, open iTerm, which I use as a Terminal.app replacement, or Terminal.app if you are so inclined.

∴ xcode-select --install
xcode-select: note: install requested for command line developer tools

A dialog opened, I chose “Install”, which finished in several minutes.


Next, run java, which prompts with a dialog that has a button “More Info” which takes you to a website where you can accept the license and download the Java .dmg file. You need the JDK, not the JRE, if you intend to run java command-line based tools.

Unable to find any JVMs matching version "1.7".
No Java runtime present, try --request to install.
∴ java
No Java runtime present, requesting install.

Once downloaded, open the .dmg (for me it was jdk-13.0.2_osx-x64_bin) and install, then restart iTerm.

Add the following to your shell (e.g. .bash_profile):

export JAVA_HOME=`/usr/libexec/java_home -v 13`

Now your Java will be available and version will be correct.

java -version


java version "13.0.2" 2020-01-14
Java(TM) SE Runtime Environment (build 13.0.2+8)
Java HotSpot(TM) 64-Bit Server VM (build 13.0.2+8, mixed mode, sharing)

Apps like RubyMine should work now, well, at least launch.


Update Homebrew. NOTE: If the update fails you may need to do cleanup first, see below.

brew update

Run a bit of cleanup.

brew doctor


Rather than use the Homebrew GPG (brew install gpg) I have switched to using the GPG Suite, which provides a DMG based install.


My pre-existing rbenv installation was working fine for most rubies, though some had to be reinstalled from scratch. TBH though, it is a great idea to reinstall them all from scratch, as some issues, like OpenSSL issues, may only become apparent later on.

rbenv uninstall 2.5.1
rbenv install 2.5.7

Additionally, I ran into some issues with a dependency on libxml2.

brew upgrade cmake
brew install libxml2
echo 'export PATH="/usr/local/opt/libxml2/bin:$PATH"' >> ~/.shared/paths # NOTE: change the end to ~/.bash_profile or somewhere appropriate
bundle config build.libxml-ruby --with-xml2-config=/usr/local/opt/libxml2/bin/xml2-config --with-xml2-dir=/usr/local/opt/libxml2 --with-xml2-lib=/usr/local/opt/libxml2/lib --with-xml2-include=/usr/local/opt/libxml2/include
bundle install


I also took the opportunity to upgrade to the latest Postgres.app. Alternatively you can install postgres with brew install postgres. I choose Postgres.app because it is supported directly by Heroku, and I like to think there is a parity win there somewhere.


Mostly I followed this gist, and this gist.

brew tap homebrew/services
brew uninstall mysql@5.7
brew install mysql@5.7
brew services list
brew services start mysql@5.7
brew link mysql@5.7 --force
mysql -V
bundle config build.mysql2 --with-ldflags=-L/usr/local/opt/openssl/lib --with-cppflags=-I/usr/local/opt/openssl/include
bundle install

End Result


Hero image (cropped) by manos koutras