The currently described updates to ZenCart are done all around the DB, its architecture, and improving its performance. To summarise from the ZenCart forums:

New Database Driver Layer
Extremely light/flexible drivers make it easier to support other Database Types
Preliminary support for innodb and mysql transactions

Sql Caching system rewritten
Much easier to add new caching types
Preliminary Support for Memcache

Use of MPTT for category structure
Reduces number of queries needed to ‘describe’ the category structure
Improves user experience thru reduced page load times

Supporting Classes to reduce query load
Hugely reduces queries needed
Reuses queries using Cache to further improve performance

The roadmap for ZenCart ver 1.4 promises the following updates to the code (summarized):

• Better usage of PHP 5.2 features. This also means 5.2 will be the new minimum requirement.
• More Object Oriented code, less of the old osCommerce code.
• Lots of DB improvements (some is described above, seems more is yet to come).
• Category structure converted to MPTT format. MPTT stands for Modified Preorder Tree Traversal (explanation of MPTT).
• Performance improvements for sites with lots of product attributes.
• More function libraries converted to classes.
• Duplicate components shared between admin and catalog.
• Template system enhancements: less tables and more admin control.
• Additional notifiers for the observer system.
• Transaction support with InnoDB. Also mentioned as initial stage according to the recent posts of the updates that were done so far.
• SwiftMailer instead of phpMailer.
• Stock and SKU per product attribute.
• Security enhancements.

Keep up the good work!

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