- replace deep rope-heavy string appends with a builder-backed concat path - teach the VM, compiler, JIT glue, and GC to read, flush, and preserve builder-backed strings - keep arguments/object slot syncing and related frame semantics aligned with the new slot behavior - finish fetch-backed node:http/node:https client shims and expose node:url.parse - add regression tests for string append loops, HTTP(S) shims, and node:url exports