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:wave: Hey hey, I'm @michaelsoolee! I'm a full-stack developer, maker of one too many side projects and dad.

Compile a site with Jekyll without installing Jekyll using Docker

Written on June 10, 2019

My current choice for running my site is Jekyll, a static-site generator written in Ruby. Since I ditched Wordpress back in 2013, I’ve been using Jekyll exclusively. It is a lot easier to get up and running on Jekyll instead of setting up Wordpress, it does still have some road blocks in getting it up and running.

Since 2013, there’s been numerous times that I’ve had to set up a new computer, which meant getting Jekyll up and running from scratch. That usually means installing Homebrew, rbenv, Ruby and then Jekyll and crossing my fingers and hoping that everything runs the first time. Not to mention also getting git configured so that I could commit back to the Github repo that has all the files for the site.

Last week I started taking another look at Docker. Docker is technology that lets you run your application in containers all from a configuration file. This is mighty powerful because it allows you to avoid the old dev adage of, “It worked on my computer”.

With Docker I discovered that I could compile or even serve my Jekyll site locally without going through the entire fuss of getting Jekyll up and running on my local machine. Although you don’t have to install any Jekyll dependencies, there is the need to install Docker to get Docker running. But I’ve found it really straightforward because they provide an app which provides the CLI and setup.

Building your Jekyll project with Docker

Once Docker is installed and set up on your machine, you can build your Jekyll project by running this command from the command line within the project folder,

docker run --rm -it --volume="$PWD:/srv/jekyll" --volume="$PWD/vendor/bundle:/usr/local/bundle" --env JEKYLL_ENV=production jekyll/jekyll:3.8 jekyll build

What this command does is:

  • --rm automatically removes the container when it exits
  • --volume="$PWD:/srv/jekyll" takes the current directory indicated by $PWD and map it to the directory at /srv/jekyll within the container so that it could build it
  • --volume="$PWD/vendor/bundle:/usr/local/bundle" this option maps the contents of the current directory’s /vendor/bundle and maps it to /usr/local/bundle. The reason for this option is so that gems could be cached and reused in future builds
  • --env JEKYLL_ENV=production in various parts of my Jekyll project, I’ve designated for it to only render if it’s for production. For example analytics shouldn’t be muddied up by my local development. This sets the environment variable for JEKYLL_ENV to production
  • jekyll/jekyll:3.8 this tells it to use the jekyll:3.8 tagged version of the Jekyll container
  • jekyll build runs the build command for Jekyll

If you’re running this command for the first time, the image for this container won’t be on your system, so it’ll grab it from the Docker registry first before it runs the container.

Unable to find image 'jekyll/jekyll:3.8' locally
3.8: Pulling from jekyll/jekyll
e7c96db7181b: Pull complete
622c94c90cb1: Pull complete
5ab26e9d8a17: Pull complete
830997f3d72a: Pull complete
1956a4eaab3f: Pull complete
36a9759f9f2f: Pull complete
Digest: sha256:deb267df3f6c2b7604b0d5a5aabcb394eec1452a053e4297cf2fb13b125e0bcf
Status: Downloaded newer image for jekyll/jekyll:3.8

One thing I ran into was this warning,

Error: could not read file /srv/jekyll/vendor/bundle/gems/jekyll-3.8.5/lib/site_template/_posts/0000-00-00-welcome-to-jekyll.markdown.erb: Invalid date '<%= Time.now.strftime('%Y-%m-%d %H:%M:%S %z') %>': Document 'vendor/bundle/gems/jekyll-3.8.5/lib/site_template/_posts/0000-00-00-welcome-to-jekyll.markdown.erb' does not have a valid date in the YAML front matter.
       Invalid date '<%= Time.now.strftime('%Y-%m-%d %H:%M:%S %z') %>': Document 'vendor/bundle/gems/jekyll-3.8.5/lib/site_template/_posts/0000-00-00-welcome-to-jekyll.markdown.erb' does not have a valid date in the YAML front matter.

To fix this I had to modify my project’s _config.yml file. Within your project if you’ve got an excluded section defined, add vendor to it.

  - "package.json"
  - "README.md"
  - "publish.sh"
  - "vendor"

Now running the docker run command from above should work and you should see your site built within the _site folder within your project. If you’ve got your project versioned with git it’s probably also a good idea to now add the vendor folder to your .gitignore file.

Serving your Jekyll project with Docker

Instead of compiling if you’d like to instead serve your Jekyll site to do some local development, you can also do that using Docker by running this command,

docker run --rm --volume="$PWD:/srv/jekyll" --volume="$PWD/vendor/bundle:/usr/local/bundle" --env JEKYLL_ENV=development -p 4000:4000 jekyll/jekyll:3.8 jekyll serve

The only difference between the serve command versus the build command above is that I pass it an environment variable of JEKYLL_ENV=development, as I mentioned this is because I have certain sections of my site set up to build only in a production environment.

First step to making your website responsive

Written on June 5, 2019

The very first step on making your website responsive after putting together content is to add a meta tag with the name attribute set to viewport between your site’s head tags.

The meta tag should look like this,

<meta name="viewport" content="width=device-width, initial-scale=1">

What this meta tag does is to tell the browser to set its viewport to be scaled to fit the screen of the device you’re viewing it on.

In your site’s head tags, this is what it should look like,

<!DOCTYPE html>
<html lang="en">
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Hello reader!</title>


Adding this single line to your HTML file will set you up in the right direction to make your website responsive.

Precompiling Rails assets for production

Written on June 3, 2019

If you’re deploying your Rails application to a production environment, it’s ideal to precompile your assets. To do this, you’ll want to run,

RAILS_ENV=production rails assets:precompile

RAILS_ENV=production tells Rails to compile the production version of the assets.

assets:precompile is a Rails provided rake task that has instructions for compiling the assets.

Access iCloud Drive quicker in Terminal by creating a symbolic link (symlink)

Written on May 31, 2019

Accessing iCloud Drive isn’t so obvious from the Terminal because Apple uses this weird path.

~/Library/Mobile\ Documents/com\~apple\~CloudDocs

Fortunately you can use a symbolic link or a symlink so that you could easily access your documents in iCloud Drive from the terminal with something like this,


You can do this using the link command or its alias ln from Terminal. So let’s say we’ll want to create a symlink to iCloud in your home folder ~. You’ll want to run this command,

ln -s ~/Library/Mobile\ Documents/com\~apple\~CloudDocs ~/iCloud

-s in the command above is the option according to man link the manual pages, is to create a symbolic link.

Then we pass the source folder and then pass in the desired destination folder, which in this case I used ~/iCloud.

So now from the command link, I can easily get to my notes folder in iCloud by typing in this in Terminal,

atom ~/iCloud/notes

iCloud Drive path in Terminal

Written on May 31, 2019

Recently I started putting my markdown notes into iCloud Drive instead of Dropbox. I’m already part of the Apple ecosystem and paying for an iCloud subscription so I thought it made sense to move my markdown notes there.

One of the common commands I run on my MacBook Pro in Terminal is my editor of choice and then the path to my notes folder. It was pretty obvious before when all my notes was in Dropbox, but it wasn’t so obvious with iCloud Drive.

~/Library/Mobile\ Documents/com\~apple\~CloudDocs

~/ being the user’s home folder.

So now if you want to say open up a folder called notes in iCloud Drive using Atom you’d run this command.

atom ~/Library/Mobile\ Documents/com\~apple\~CloudDocs/notes

Not the prettiest or even the most obvious path and I hope Apple moves it to make it more obvious in the future.

Alternatively, you could create a symbolic link or symlink for short so you could access your iCloud Drive from the Terminal with a cleaner and more obvious path.

Simplicity is powerful

Written on May 30, 2019

I’ve had an idea floating around in my mind for a few months. Tonight I finally wanted to start working on it, but I didn’t want to bother taking the time to set up all that was necessary to get Jekyll or a Rails app going. So I created a folder with a single HTML, added some CSS and pushed it all to Netlify.

The setup was simple, but oh so powerful. It was powerful in that I was able to quickly get my idea from my brain and onto the screen. Because I don’t have to worry about a database or framework, I’m focusing on the look, feel and mechanics and am able to iterate on it quickly.

Sometimes the most primitive of tools in your toolbox can be the most powerful for the task at hand.