custom widget or extension yii2

Question

I want to use off canvas of another widget/extension in my website, but I didnt get what I need on github. I am wondering if it possible to custom extension, what should I do (read/learn) something so I can use a custom yii2 extension.

I have tried offcanvas extension on widget.

https://github.com/hull-agency/yii2-foundation

When I was trying to install the following message appears:

Your requirements could not be resolved to an installable set of packages.

  Problem 1
  - The requested package custom/utils could not be found in any version, there may be a typo in the package name.

Potential causes:
 - A typo in the package name
 - The package is not available in a stable-enough version according to your minimum-stability setting
   see  for more details.

whats is really meant? I think it cant be used or what? Is the package really a typo?

Answer 1

Add following lines,

   "minimum-stability": "dev",
   "prefer-stable": true,

in composer.json of your project directory, than install widget/extension.