...
Create a database when installing module (5h)
Controller (4h5h)
Model/Resource Model/Collection (1d)
EAV and extension attributes (1d5h)
Layout (1d5h)
Event (4h)
Plugin/Rewrite (5h)
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Admin Customize: Menu/System/ Grid/Form/UiComponent (2d1.5d)
Another Technique (2.5d2d)
Cronjob, Command line: 1d 4h
Indexer: 4h
Knockout js: 1d