Frequently Asked Questions

What makes Ruby on Mac special?

There are many ways to set up a working Ruby development environment on a Mac. I am in no way claiming that Ruby on Mac is the only way. Nor am I claiming that other approaches are wrong.

What I am claiming is that Ruby on Mac is the fastest and easiest way because it’s simple, it’s reliable, and it works perfectly every time.

‘Simple’ means all you have to do is run a single command, and Ruby on Mac will do all the hard work for you. ‘Reliable’ means it will work with any supported Intel and Apple Silicon Mac, and it will work every single time. I know it works because the script has been run successfully on thousands of Macs, from brand new Macs to ones with the messiest development environments.

It’s the same script I use to set up and maintain my personal Macs, and I test it several times per week on 4 Macs: my main M1 MacBook Air and Intel iMac that I use every day, and my spare Intel MacBook Air and M1 Mac Mini for testing various scenarios.

For example, if you try to install Ruby 3.2.x with either asdf or rbenv (two of the most popular tools) on a brand new Apple Silicon Mac, they will fail with an error like this:

Last 10 log lines:
  Check ext/psych/mkmf.log for more details.
*** Fix the problems, then remove these directories and try again if you want.
Generating RDoc documentation
warning: It seems your ruby installation is missing psych (for YAML output).
To eliminate this warning, please install libyaml and reinstall your ruby.
uh-oh! RDoc had a problem:
cannot load such file -- psych

run with --debug for full backtrace
make: *** [rdoc] Error 1

That’s because they leave it up to you to know and remember which prerequisite tools you need to install first. In addition, with asdf and rbenv, you can’t install the latest version of Ruby as soon as it’s released. You have to wait for the maintainers to manually add the latest version, which sometimes takes several days. And then you have to remember to manually update ruby-build.

With Ruby on Mac (which uses a custom version of ruby-install), these errors don’t happen because it automatically installs everything you need (and nothing you don’t), it configures Ruby in the best possible way, and you can install the latest version as soon as it’s released, without having to update any tools manually.

Ruby on Mac Ultimate also installs Ruby faster than any other version manager, and twice as fast as rbenv and asdf (2 minutes vs 4 minutes).

The best part is that Ruby on Mac Ultimate supports all the popular version managers: asdf, chruby, frum, rbenv, and rvm. If you have a strong preference for a particular tool, you can still use it, and you won’t have to deal with the installation issues that you would experience if you were to use it outside of Ruby on Mac.

That’s not to say that there have never been any issues. Sometimes, there are bugs in the tools that Ruby on Mac depends on, and sometimes Apple makes changes that break Ruby, as happened in September 2022, and then again when Ventura was first released. The few times this has happened, I had a fix for Ruby on Mac customers within 24 hours, while others had to wait several days or weeks for the official fixes, or spend time trying to figure out the issue and how to fix it.

I also improve the scripts regularly, and sometimes I introduce bugs. Or maybe a customer has a unique scenario that I haven’t seen before. In those cases, I fix the bugs within minutes of discovering them.

Ruby on Mac is unique because it gives you the peace of mind that you will always have a working Ruby dev setup. This will save you months of your time, and thousands of dollars compared to maintaining your own script, or doing everything manually every time.

Is there a money-back guarantee?

The short answer is yes, but there are some important disclaimers! Make sure to carefully read this entire section, as well as the next two sections: what is not covered by the guarantee? and will the script fix issues with my existing Ruby projects?.

If Ruby on Mac doesn’t install all supported tools successfully even after cleaning everything up with “reset” mode, I will personally set up your Mac for you, or you can send me an email within 30 days and I’ll give you a full refund.

The first time you run any version of Ruby on Mac on a clean installation of a supported macOS (as provided by Apple), it is guaranteed to set up a working Ruby environment. One way to confirm this is that you should be able to create and run a brand new Jekyll or Rails project (using the instructions in these links).

If you already had development tools installed, Ruby on Mac is not guaranteed to work the first time you run it (although it might). If it doesn’t, you can use the “reset” mode to safely back up and clean up your dev setup in 1 minute. And when you run the script again in “normal” mode, it is guaranteed to install everything successfully.

Once Ruby on Mac installs everything successfully, it will prompt you to open the Post-Installation Guides. It’s very important to read all of it thorougly to avoid confusion and headaches.

What is not covered by the guarantee?

In addition to unsupported macOS versions, I can’t guarantee Ruby on Mac will work on a Mac that was provided by your employer with software or files preinstalled on it that didn’t come from Apple.

Ruby on Mac is also not guaranteed to fix issues that are specific to your existing projects. If Ruby on Mac installed everything successfully, but you still can’t run your existing project, that most likely means the issue is specific to your project. In that case, I can’t give you a refund, but I can certainly help you. Please read the next FAQ (below this one) for more details.

Will the script fix issues with my existing Ruby projects?

Depending on which version of Ruby your old project is using, it might not work out of the box. For example, after setting everything up properly with Ruby on Mac, if your project is configured to use Ruby 2.6.10, you might get an error similar to the ones below when running bundle install:

Your user account isn't allowed to install to the system RubyGems.


Your Ruby version is 3.1.4, but your Gemfile specified 2.6.10

The first error means that the current active version of Ruby is indeed 2.6.10, but it’s the one that came preinstalled on your Mac, which you never want to use. The second error means that your project is set up to use Ruby 2.6.10, but the current active version is 3.1.4.

In both cases, the solution is to either update your project to a newer version of Ruby (such as one of the versions Ruby on Mac installed for you), or buy Ruby on Mac Ultimate, which lets you install a proper version of 2.6.10. You will not be able to install Ruby 2.6.10 or older with Ruby on Mac Prime.

Unless you prefer to get your project up and running with 2.6.10 first before updating to a newer version, I recommend trying to update your project directly to a newer version, and I have a free guide that explains how and why to upgrade the Ruby version in your project. If you have a proper Ruby dev setup, try this first before buying Ruby on Mac.

The Ultimate version of Ruby on Mac also comes with a free 30-minute consultation if you need help updating your old projects.

Similarly, if you have an older project with outdated or unsupported gems, running bundle install or bundle exec pod install or bin/rails s might result in errors, even if you’re using a newer Ruby version. In most cases, updating those gems to the latest version is the solution. However, if you’re on an M1/M2 Mac, this will only work if the latest version of those gems is compatible with Apple Silicon.

Here are some gems that are not fully compatible with Apple Silicon (M1/M2). I recommend replacing them with more modern alternatives, or asking the maintainers if they’re willing to update them.

If you haven’t yet run Ruby on Mac, and you’re not able to install the latest version of a supported gem (meaning the gem says it works on Apple Silicon Macs), then Ruby on Mac is guaranteed to solve that problem. After running Ruby on Mac, if you can’t install the gems in your old project, or if you’re not able to run your project, that most likely means those errors are specific to your project, and not Ruby on Mac. I recommend updating any gems mentioned in the errors.

If you need help updating older projects, try these free guides I’ve written:

If you prefer personalized help, the Ultimate version of Ruby on Mac includes a 30-minute consultation with me (worth $150 on its own), among many other exclusive time-saving features.

Is there a student discount?

Yes! If you’re actively enrolled in an educational program, you can receive 20% off the full cost of Ruby on Mac. This discount can’t be combined with any other discounts.

This discount is intended for full-time or part-time students, including coding bootcamps like General Assembly.

To get your unique coupon code, email me at with proof of enrollment.

Do you support Purchasing Power Parity (PPP)?

Yes! If you visit from a country with low purchasing power, you should see a banner at the top of this site with a coupon code you can use. If you don’t see a banner, try turning off your VPN. If you still don’t see the banner, email me and I’ll look into it.

Which payment methods do you accept?

I accept all payment methods that are supported by Paddle, the service I use for payment processing:

  • Credit Cards (including Mastercard, Visa, Maestro, American Express, Discover, Diners Club, JCB, UnionPay, and Mada)
  • PayPal
  • Alipay (in Early Access)
  • iDEAL
  • Google Pay (Chrome only)
  • Apple Pay (Safari only)
  • Wire Transfers (ACH/SEPA/BACS)

I already know how to install Ruby, what do I gain from Ruby on Mac?

You will save a ton of time, which is our most limited and valuable resource. If you’re setting up a new Mac, or are planning on buying one soon, or getting one for a new job, would you rather spend a whole work day setting everything up manually, or run a single command that will do it all for you in about 15 minutes?

I’m not a developer and/or I’m new to Mac, will I be able to use Ruby on Mac?

Absolutely! Ruby on Mac is designed to be beginner-friendly. Follow the detailed step-by-step instructions, and you’ll be up and running in minutes. If you get stuck and the documentation isn’t helpful, I’ll be happy to walk you through it personally over Zoom.

Which versions of macOS are supported?

Ruby on Mac runs on Ventura, Monterey, and Big Sur.

Older macOS versions might work, but I do not provide support for versions older than Big Sur, and for beta or release candidate versions. No refunds will be given for script failures on unsupported OSes.

Which processors are supported?

Ruby on Mac runs on Intel, and all Apple Silicon chips (M1/M2).

Which versions of Ruby will I be able to install?

Ruby on Mac automatically installs the latest version of Ruby by default (currently 3.2.2), as well as 3.1.4. Ruby on Mac Ultimate also installs 2.7.8 for wider compatibility. You’ll also be able to run a single command to install other Ruby versions. If you need to install 2.6.10 or older, you’ll need to buy Ruby on Mac Ultimate.

Note that the oldest 2.7.x version you can install on an Apple Silicon Mac is 2.7.2. If your project currently specifies 2.7.0 or 2.7.1, you should update your project to use 2.7.8. Read my guide that explains how and why to upgrade the Ruby version in your project.

To switch between versions, you’ll use the “chruby” tool by default. If you prefer using a different tool for switching between Ruby versions (such as asdf, frum, rbenv, or rvm), the Ultimate version of Ruby on Mac lets you set your preferred version manager.

All of this explained in the detailed documentation that comes with Ruby on Mac.

Can I upgrade from Prime to Ultimate?

Absolutely! In the Ruby on Mac documentation, you’ll find the coupon code to upgrade to Ultimate. The upgrade cost will be the difference between what you paid originally and the full cost of Ultimate at the time of the upgrade.

Note that the price of Ultimate will definitely increase in the future, so it will cost more if you wait too long to upgrade.

On how many computers can I run the script on?

For individual licenses, as many as you want, as long as they are your personal computers.

If you purchased an Ultimate Team license, you can share it with your entire team up to 25 people. See the License for more details about what you can and can’t do.

How long can I keep using Ruby on Mac?

Ruby on Mac is a one-time purchase, with no recurring subscription. When you purchase any Ruby on Mac version, you have access to all of the content in that version forever.

If you buy the Prime version, you’ll get free updates and bug fixes for one year. After that, if it stops working for some reason, due to macOS changes for example, you’ll need to buy it again to get another year of updates.

If you buy the Ultimate version, you get unlimited free updates.

What does “free updates” include?

Since I use Ruby on Mac regularly to set up my own computers and keep them secure and up to date, I’m making improvements regularly to keep it as easy to use as possible, and to make sure it continues to work on current and future macOS versions.

Note that Ultimate customers always get updates first, and new features will only be available for Ultimate customers. Prime updates will be limited to bug fixes and making sure it continues to work when new macOS and Ruby versions are released.

Can I purchase a license for my entire team?

Yes! The team license is available with the Ultimate version of Ruby on Mac. You can purchase a license that you can share with up to 25 people for a one-time fee of $899 USD.

Buy an Ultimate Team license for $899 USD

Can I upgrade to a team license later?

Yup! If you’re a solo developer, you can start with a regular license, and then upgrade to the Ultimate Team license later if other developers join your team.

When you’re ready to upgrade, email me at and I’ll take care of it.

Can I get a receipt, so I can be reimbursed?

Right after purchasing, you’ll be emailed a receipt/invoice from Paddle, the service I use to process payments. You’ll be able to add whatever name and address is necessary to get reimbursed.

You can also add your VAT number, to have any VAT charges reimbursed.

You have another question?

Email me at and I’ll do my best to get you an answer within a few working hours.