installer problem at composer magento/core ?

[sekroots]

Preparing the Magerun Configuration
Installing Magento
Composer could not detect the root package (andreaskoch/dockerized-magento) version, defaulting to '1.0.0'. See https://getcomposer.org/root-version
Loading composer repositories with package information
Updating dependencies
Your requirements could not be resolved to an installable set of packages.

Problem 1
- Root composer.json requires magento/core, it 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 https://getcomposer.org/doc/04-schema.md#minimum-stability for more details.
• It's a private package and you forgot to add a custom repository to find it

Read https://getcomposer.org/doc/articles/troubleshooting.md for further common problems.