From publisher blurb:
The School of the Dilettante emphasizes a reactionary approach to magic, valuing knowledge outside of the realm of the Arcane just as much as within. Instead of focusing on the minutia of a particular school of magic, these wizards espouse the fundamental principles of magic to adapt to any situation. Though they are often more concerned with the purest academic pursuits of knowledge, the services of a trained wizard are almost universally valued. This demand comes from several sources, ranging from legitimate to criminal, and is met by industrious wizards whose focus, paradoxically, lies within having no focus.
Building off of the existing Fifth Edition rules to build a wizard character, the School of the Dilettante gives you options to build a flexible spellcaster who can readjust their prepared spells, and even derive other classes' spells using fundamental theories of magic.