A new way to manage memory: no garbage collection, extremely fast & safe access

U has no garbage collector. Ownership is a DAG — strong references point from parent to child, never upward or cyclically. When an owner's refcount hits zero, its entire subtree dies. No tracing, no mark-sweep, no pause. The cost of deallocation is proportional to what was allocated by that owner, not to total heap size.

Back-references use +R(parent) annotations. The compiler treats them as weak: they don't contribute to the reference count and resolve to none when the referent dies. The linter enforces the DAG structure using Tarjan's SCC algorithm on the type-reference graph — any cycle must have at least one +R(parent) edge, or the program is rejected.

Every owner has a slab chain. Allocations bump a pointer within the current slab. When a slab fills, a new slab twice the size is linked in.