Composer create-project take forever to download and create project? [duplicate]

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• Why is php composer so slow? 3 answers

Why does composer create-project take forever to download and create project?

I have tried:

Slim:

$ composer create-project slim/slim-skeleton slim-app

Laravel:

$ composer create-project laravel/laravel lavavel-app"5.0.*" --prefer-dist

It is just extremely slow:

Installing slim/slim-skeleton (3.1.2)
  - Installing slim/slim-skeleton (3.1.2) Downloading: 100%         
Created project in mr-simon-cohen-slim
Loading composer repositories with package information
Updating dependencies (including require-dev)
(it just stuck here...)

Any ideas?

I'm on Kubuntu 16.10.

via teelou