Ruby 2.6.10 setup on macOS (Apple Silicon)

This guide shows how to set up an old Ruby + Rails environment on a modern macOS (Apple Silicon). As per October 2025, this works on an M1 MacBook Pro (2020) on macOS Sequoia 15.6.1. I assume it will also work on Tahoe 26.0, but I haven't tested it yet.

This is what you’ll end up with:

Ruby 2.6.10
OpenSSL 1.1 (needed for Ruby < 3.0)
MySQL 5.7

1. Install requirements

Make sure you have Homebrew installed:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Then install these dependencies via brew:

brew install chruby zlib readline libyaml wget make gcc

2. Setting up chruby

Add the following to your ~/.zshrc (or ~/.bashrc if using bash):

# chruby setup
source $(brew --prefix chruby)/share/chruby/chruby.sh
source $(brew --prefix chruby)/share/chruby/auto.sh

Reload shell:

source ~/.zshrc

3. Install OpenSSL 1.1 and (optionally) MySQL 5.7, as seen on this Gist comment (thank you ferrucc-io!)

Please refer to the above Gist comment if you run into errors with this step.

Install OpenSSL 1.1 (mandatory for Ruby 2.6.10)

brew tap homebrew/core --force

# Restore [email protected] formula from an older commit
sudo curl -fL "https://raw.githubusercontent.com/Homebrew/homebrew-core/6c907880b95a3702348c1fcce1c661fcc03336e5/Formula/o/openssl%401.1.rb" \
  -o "/opt/homebrew/Library/Taps/homebrew/homebrew-core/Formula/o/[email protected]"
sudo sed -i '' '/disable! date: "2024-10-24", because: :unsupported/d' /opt/homebrew/Library/Taps/homebrew/homebrew-core/Formula/o/[email protected]

# Install OpenSSL 1.1
brew tap-new local/old-openssl
cp /opt/homebrew/Library/Taps/homebrew/homebrew-core/Formula/o/[email protected] \
   $(brew --repository local/old-openssl)/Formula/[email protected]
brew install local/old-openssl/[email protected]

Install OpenSSL certs:

For this, make sure OpenSSL 1.1 is installed in /opt/homebrew/opt/[email protected]

Check first if /opt/homebrew/etc/[email protected] exists, if so, replace the mkdir -p below with a cd

mkdir -p /opt/homebrew/etc/[email protected]
wget https://curl.se/ca/cacert.pem -O /opt/homebrew/etc/[email protected]/cert.pem
echo 'export SSL_CERT_FILE=/opt/homebrew/etc/[email protected]/cert.pem' >> ~/.zshrc
source ~/.zshrc

If your project depends on MySQL 5.7, you’ll need to re-tap the old formula because it’s been removed from Homebrew. Example steps:

# Restore [email protected] formula from an older commit
sudo curl -fL "https://raw.githubusercontent.com/Homebrew/homebrew-core/6c907880b95a3702348c1fcce1c661fcc03336e5/Formula/m/mysql%405.7.rb" \
  -o "/opt/homebrew/Library/Taps/homebrew/homebrew-core/Formula/m/[email protected]"
sudo sed -i '' '/disable! date: "2024-08-01", because: :unsupported/d' /opt/homebrew/Library/Taps/homebrew/homebrew-core/Formula/m/[email protected]

# Install MySQL 5.7
brew tap-new local/old-mysql
cp /opt/homebrew/Library/Taps/homebrew/homebrew-core/Formula/m/[email protected] \
   $(brew --repository local/old-mysql)/Formula/[email protected]
brew install local/old-mysql/[email protected]

4. Install Ruby 2.6.10

Use ruby-install with these OpenSSL/Zlib/Readline flags:

export OPENSSL_DIR="$(brew --prefix [email protected])"
export CPPFLAGS="-I$OPENSSL_DIR/include"
export LDFLAGS="-L$OPENSSL_DIR/lib"
export PKG_CONFIG_PATH="$OPENSSL_DIR/lib/pkgconfig"
export RUBY_CFLAGS="-Wno-error=deprecated-declarations"

wget https://cache.ruby-lang.org/pub/ruby/2.6/ruby-2.6.10.tar.gz
tar -xzf ruby-2.6.10.tar.gz
cd ruby-2.6.10

./configure \
  --prefix="$HOME/.rubies/ruby-2.6.10" \
  --with-openssl-dir="$OPENSSL_DIR" \
  --with-readline-dir="$(brew --prefix readline)" \
  --with-zlib-dir="$(brew --prefix zlib)" \
  --with-libyaml-dir="$(brew --prefix libyaml)"

make clean
make -j$(sysctl -n hw.ncpu)
make install

(Installs Ruby into ~/.rubies/ruby-2.6.10)

5. Switch to Ruby 2.6.10

Run this:

chruby 2.6.10

To make this Ruby version the default, add this to ~/.zshrc:

source $(brew --prefix chruby)/share/chruby/chruby.sh
source $(brew --prefix chruby)/share/chruby/auto.sh

chruby ruby-2.6.10

Note that the first two lines should probably have been added in a prior step.

6. Install bundler

Running a legacy version of Ruby means we are likely to run an older Rails version, therefore we need an older version of bundler:

gem install bundler -v 1.17.3

7. Verify Setup

Check versions:

ruby -v     # ruby 2.6.10p210
bundler -v  # Bundler 1.17.3
mysql -V    # mysql  Ver 14.14 Distrib 5.7.x

Done.

That's just about everything.

Alternatives

If OpenSSL is giving you a hard time with installation, compile it from the source.

wget https://www.openssl.org/source/openssl-1.1.1w.tar.gz
tar -xvf openssl-1.1.1w.tar.gz
cd openssl-1.1.1w
./config --prefix=/usr/local/opt/[email protected] --openssldir=/usr/local/opt/[email protected] shared zlib
make -j$(sysctl -n hw.ncpu)
make test
sudo make install

Make sure to replace brew --prefix [email protected] in the above steps with the directory that OpenSSL 1.1 is installed in, which should be /usr/local/opt/[email protected].

If you decide to do this step, make sure to install the OpenSSL cert and point Ruby to the right path:

sudo mkdir -p /usr/local/etc/[email protected]
wget https://curl.se/ca/cacert.pem -O /usr/local/etc/[email protected]/cert.pem
echo 'export SSL_CERT_FILE=/usr/local/etc/[email protected]/cert.pem' >> ~/.zshrc
source ~/.zshrc

daffaromero/ruby_setup.md