Nowadays it is fairly easy to intercept and modify mails globally before they are sent. All you have to do...

When you have a multi-server setup, you'll be adding a new server from time to time. Before doing...

Rails supports time zones, but there are several pitfalls. Most importantly because Time.now and Time.current are completely different things and...

This is useful if, for example, you want to use a background-image that has to scale with the width...

This card will show you how to use git rebase --onto without confusion. Use case: You've got two feature...

Webmocks hash_including is similar to RSpec::Mocks::ArgumentMatchers#hash_including. Be aware that hash_including (webmock v3.0.1) doesn't...

Typhoeus has a different way of representing array params in a get request than RestClient. Typhoeus: http://example.com/?foo[0]=1&foo[1]=2&foo[2]=3

Middleman is a static page generator that brings many of the goodies that Rails developers are used to.

Sometimes, through some firewall or proxy misconfiguration, you might have to deploy to a server that cannot access the git...

Dump this method into your Ruby console to quickly print data in columns. This is helpful for e.g. comparing attributes...

Separate subject from body with a blank line Limit the subject line to 50 characters (max. 72), include reference (unique...

Database connections are not thread-safe. That's why ActiveRecord uses a separate database connection for each thread.

In modern default RSpec configurations, your tests are usually run in random order. This helps to detect "flickering" tests that...

You can use wscat: sudo apt-get install node-ws # wscat -c ws://echo.websocket.org connected (press CTRL+C to quit...

In case you want to require a gem, that is not in the Gemfile of you bundle and therefore not...

This card compares patterns to store trees in a relation database like MySQL or PostgreSQL. Implementation examples are for the...

The parallel-gem is quite easy to use and can speed up rendering time if you want to render the...

Some pseudo-elements need to be addressed with vendor prefixes. E.g. ::selection is not supported by Firefox, you need to...

Sometimes you want/have to send specific http(s) requests. You can do that easy with curl or just write the...

For the initial setup or changes in the sentry reporting it might be useful to enabled reporting of sentry in...

ImageMagick has a command line tool called identify which can read image metadata: >identify -verbose DSC00136.JPG Image: DSC00136.JPG Format: JPEG...

Barby is a great Ruby gem to generate barcodes of all different sorts. It includes support for QR codes via...