DrupalCon Vienna 2017: Symfony in Drupal 8: How much and what does Drupal inherit from Symfony

Focus audience: Drupal 8 back-end *programmers*
Experience level for attendees: Beginner/Intermediate
Presentation time: 45 mins; Q&A time: 15mins

Content:

This session is for people who are new to Drupal 8 programming and would want to know about how drupal is structured and how much it inherits from Symfony.
This session will be a high level, conceptual, overview of Drupal 8's internals and how they're implemented. Comparisons will be made to corresponding components in Symfony.
Main topics covered:

How Drupal 8 retains all the features of Drupal 7 (site-building-wise) but is a complete rewrite under the hood.
How Drupal 8 does away with procedural programming (but not actually :P) and adopts OOP for good.
Why Drupal's mantra of "Proudly Found Elsewhere" is awesome and what some of those "elsewhere" projects are.
Brief description Drupal 8 hierarchical structure:
DrupalKernal and PHP components at the bottom
Base system (block, entity, form etc) and modules in the middle
Theme system and twig at top.
High level overview of Symfony components used in Drupal and how these components are used by DrupalKernel and Drupal base system.

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