Only copy strings when they are mutated. This avoids copying strings in cases where neither the copy nor the original would be modified during the lifetime of the copy, e.g. when passing strings by-value. This is purely an optimization.
Implement all of the string instructions that I could get the compiler to generate code for. Still ASCII-only.
Overhaul the VM design to more closely resemble System40.exe. See system4.md for further details.
Nunuhara Cabbage