Getting Started with CodeIgniter 4 PreAlpha 1

So migration will be impossible without rewriting your app.

Ya sure. Rewrite means I can not use existing code in any situation?

Your upgrade will equal a rewrite.. Understand it as you want.

No more direct core overwrites with MY_, no more $this->load , no more get_instance, required namespaces on all files where you are extending some code classes as controllers as models and many other small or big differences ..

I count such app "upgrade" as rewrite. It won't be just a regular upgrade..

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