New language

Runtime optional.
GC optional.
Static typing.
Binary compatibility with C.
Algebraic types.
Lambdas.
Traits.
Safe shared mutable state.

>>30
It's true that you can't move allocated data but you can defragment as you free and reallocate (...) in long-running programs
O(n²).

compacting
O(n), also with less cache misses since defragmenting is done in large contiguous pieces.

Please note that I am against GC implementations that do not allow immediate freeing and/or manually-managed block groups.