## Add the Ruby option [#add-the-ruby-option]
In `main.tf`, find the `data "coder_parameter" "languages"` block.
Add a Ruby `option` after the last existing option, before the parameter's closing brace:
```tf
option {
name = "Ruby"
value = "ruby"
icon = "/icon/ruby.svg"
}
```
The `option` block must sit at the same indentation as the other `option` blocks inside the parameter.
Coder reads the parameter's choices from these blocks, so a misplaced `option` doesn't appear in the form.
The `icon` value points at an icon bundled with your Coder deployment.
To browse the full set and copy a path, open `https:///icons`.
Now publish the change as a new template version:
In the web editor, make the edit above in `main.tf`.
Select **Build**, wait for the build to pass, then select **Publish**.
Make the edit in `~/coder-quickstart/main.tf`, then publish a new version:
```sh
coder templates push -d ~/coder-quickstart -y quickstart
```
## Add Ruby to your workspace [#add-ruby-to-your-workspace]
Your workspace from [Launch your first workspace](/beta-docs/get-started/) is still on the old template version.
Update it to the version you just published, and add Ruby to its **Programming Languages** selection:
1. From your workspace, open **Workspace settings** (top right), then select **Parameters**.
2. Add **Ruby** to the **Programming Languages** parameter.
3. Apply the change. Coder updates the workspace to the new template version and restarts it with Ruby selected.
Update the workspace and re-select its parameters.
Replace `` with your workspace's name (run `coder list` to see it):
```sh
coder update --always-prompt
```
When prompted for **Programming Languages**, add **Ruby**, then let the workspace rebuild.
Adding the Ruby option to the parameter shows the following:
*Programming Language dropdown parameter from the Quickstart template with Ruby*
## Check whether Ruby is installed [#check-whether-ruby-is-installed]
When the workspace restarts, open a terminal and ask for the Ruby version:
```sh
ruby --version
```
The command fails:
```txt
ruby: command not found
```
You added the option, selected it, and rebuilt the workspace, but Ruby isn't there.
Adding the `option` only changed the form.
It added Ruby to the list of choices, but nothing in the template acts on that choice yet.
A separate startup script installs each selected toolchain, and you haven't taught it about Ruby.
## Install Ruby when the workspace starts [#install-ruby-when-the-workspace-starts]
The template installs each selected language from `install-languages.sh.tftpl`, a startup script that runs when the workspace boots.
Open that file and add a branch that installs Ruby when the reader selects it:
```sh
if echo "$LANGUAGES" | grep -q "ruby"; then
if command -v ruby >/dev/null 2>&1; then
echo "Ruby: $(ruby --version | head -1)"
else
echo "Installing Ruby toolchain..."
apt_update
sudo apt-get install -y -qq ruby-full
echo "Installed Ruby: $(ruby --version | head -1)"
fi
fi
```
The script installs Ruby with `apt-get`, the package manager built into the workspace image.
Use the package manager the workspace image provides, not a personal one.
If you replace the `apt-get` line with `brew install ruby`, the build fails: the `codercom/example-base:ubuntu` image doesn't include Homebrew, so the workspace logs `brew: command not found` and Ruby never installs.
To install a personal tool like a Homebrew formula in your own workspace, refer to [Install your own command-line tools](/beta-docs/get-started/customize-your-template/install-command-line-tools/).
Publish the change, then update your workspace again:
1. In the web editor, make the edit above in `install-languages.sh.tftpl`.
2. Select **Build**, wait for the build to pass, then select **Publish**.
3. On your workspace's home tab, select **Update and restart**.
Make the edit in `~/coder-quickstart/install-languages.sh.tftpl`, then publish and update:
```sh
coder templates push -d ~/coder-quickstart -y quickstart
coder update
```
Ruby is already selected, so you don't change parameters this time.
When the workspace restarts, open a terminal and check again:
```sh
ruby --version
```
This time the workspace reports a Ruby version.
## Add a Ruby preset [#add-a-ruby-preset]
Steps 1 through 4 make Ruby selectable as a parameter and install it at startup.
The Quickstart template also ships presets: named bundles of parameter values that appear on the workspace creation form:
*Default presets with the Quickstart template*
The shipped presets cover combinations like Go and Python, but none selects Ruby, so add one to keep the parameter and preset choices in sync.
In `main.tf`, find the `# --- Presets ---` section and add a Ruby preset next to the existing ones:
```tf
data "coder_workspace_preset" "ruby_dev" {
name = "Ruby Development"
icon = "/icon/ruby.svg"
parameters = {
languages = jsonencode(["ruby"])
ides = jsonencode(["code-server", "jetbrains"])
jetbrains_ides = jsonencode(["RM"])
git_repo = ""
}
}
```
This preset adds JetBrains RubyMine as a default option for the language, but you can customize the preferred IDEs in this default based on your needs.
Publish the template again.
The next time you create a workspace, **Ruby Development** appears in the preset list and preselects Ruby:
*Updated presets with the Quickstart template*
Expanding the preset parameters after selecting **Ruby Development** shows the parameter values Coder will use to create the workspace:
*Expanded parameter values for the Ruby Development preset*
## What just happened [#what-just-happened]
You changed two different things to add one language:
* The `coder_parameter` `option` block added Ruby to the workspace creation form.
* The startup script installed the Ruby toolchain when a workspace owner selected Ruby.
A parameter collects a choice.
A startup script acts on it.
A new language needs both.
You also added support for a new preset, so workspace users can launch a workspace from this template quickly, without having to fill out the parameters manually.