WasmGC gives compilers a way to represent objects as typed, garbage-collected values in WebAssembly, rather than encoding every object inside a large block of linear memory.
Without WasmGC, a compiler commonly implements its own heap inside linear memory. It must track object layouts and references itself, and provide or bundle a garbage collector. With WasmGC, the compiler can use WebAssembly GC structures and arrays, creating references that the WebAssembly engine understands as managed references.
This changes who handles the underlying memory work: the engine can trace references and reclaim unreachable objects. The compiler still decides which language objects use this representation and must preserve the source language’s rules, such as object layout, inheritance, and identity. WasmGC supplies managed storage; it does not automatically provide an entire language runtime.
It also does not replace linear memory. Languages can still use it for byte buffers, native-style data, or existing runtime components, and a program may use both memory models. The main benefit for object-oriented languages is that ordinary WasmGC-managed objects need not be hidden behind a hand-built heap in linear memory, which can make compiled code and its GC integration more direct.
