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- Choosing a runtime architecture
- Required plug points into runtime
- Handlers - an ability to add user handlers; change system handlers?
- Extensible Metadata - an ability to collect the custom meta-data (e.g. custom annotations), this can be also achieved by using handlers
- Extensible Lifecycle Manager - define custom scopes, use spring scopes when integrating with Spring
- Extensible Custom field/parameters injection - can be used with custom annotations
- Third party dependencies (should we grow our own ATOM support or use Abdera?)
- How to modularize
- How to do unit tests (which Mock Object framework?)
- How to do integration tests
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