Install Ruby on Rails on Debian 12

I recently tried to Install Ruby on Rails on Debian 12 for a project, and while I eventually got it working, the process was far from smooth. Here’s what I did, along with the issues I faced, in case it helps others avoid the same pitfalls.

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Step 1: Install Ruby

I started by installing Ruby using the default package manager, but ran into version issues. The default Ruby version on Debian 12 was too old for Rails, so I had to remove it and install a newer version using rbenv. Here’s what I did:

1. Remove the default Ruby (if installed):

   sudo apt remove ruby
   

2. Install dependencies for rbenv:

   sudo apt install git curl libssl-dev libreadline-dev zlib1g-dev autoconf bison build-essential libyaml-dev libncurses5-dev libffi-dev libgdbm-dev
   

3. Install rbenv and Ruby:

   curl -fsSL https://github.com/rbenv/rbenv-installer/raw/main/bin/rbenv-installer | bash
   echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
   echo 'eval "$(rbenv init -)"' >> ~/.bashrc
   source ~/.bashrc
   rbenv install 3.2.2  # Replace with the version you need
   rbenv global 3.2.2
   

   Problem: After installing Ruby, running ruby -v gave me an error about missing libraries. I had to manually install libssl-dev and libreadline-dev to fix it.

Step 2: Install Rails

Once Ruby was installed, I tried to install Rails using gem install rails, but it failed due to permission issues. Here’s how I fixed it:

1. Install Rails:

   gem install rails
   

   Problem: The command failed with a permission error. I had to use --user-install to install Rails locally:

   gem install rails --user-install
   

2. Add gems to PATH:
   I added the following to my .bashrc to ensure Rails commands were recognized:

   export PATH="$HOME/.gem/ruby/3.2.2/bin:$PATH"
   source ~/.bashrc
   

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Step 3: Set Up a Rails Project

I created a new Rails project, but ran into database configuration issues:

1. Create a new project:

   rails new myapp
   

   Problem: The rails new command failed because bundler wasn’t installed. I had to install it manually:

   gem install bundler
   

2. Install dependencies:
   After fixing bundler, I ran:

   bundle install
   

   Problem: The pg gem (for PostgreSQL) failed to install because I didn’t have the PostgreSQL development libraries. I fixed it by running:

   sudo apt install libpq-dev
   

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Step 4: Run the Rails Server

Finally, I tried to run the Rails server, but it wouldn’t start:

1. Start the server:

   rails server
   

   Problem: The server failed to start because JavaScript runtime was missing. I installed Node.js to fix it:

   sudo apt install nodejs
   

Conclusion

While I eventually managed to Install Ruby on Rails on Debian 12, the process was frustrating due to missing dependencies and permission issues. If you’re trying this, make sure to:

• Use rbenv for Ruby installation.
• Install all necessary development libraries (e.g., libssl-dev, libpq-dev, nodejs).
• Use --user-install if you encounter permission errors.