Refactor handlers for better readability

**Description**
Currently core lacks proper backup support.

**Proposed solution**
Add configurable backup with sensible defaults.

**Priority**: Low/Medium

Start by locating the core handler implementation referenced by the title and the issue's mention of core. The issue does not name files, tests, backup behavior, or default values, so clarify the expected configurable backup and sensible defaults before changing anything. Done means backup support is implemented with agreed defaults and validated by appropriate tests.

Written by the indexing model from the issue text.