Module layout 

Static field-offset table for the host <-> wasm binary handshake.

Spec: docs/internal/adr/wasm-binary-layout-v1-2026-05-16.md, “basic type layout” + “slot alignment rule” sections.

v1 scope (Phase 2.a / 2.b / 2.c):

• Phase 2.a / 2.b: the four scalar leaves — Int, Float, Bool, Unit — are laid out inline. Each field’s start offset is rounded up to its alignment; the root is padded to root_align so the next record starts aligned.
• Phase 2.c+: variable fields (String, List<T>, nested schemas, Option<T>, and Result<T, E>) use pointer indirection. Each contributes a fixed-area u32 pointer slot (size = 4, align = 4); the payload lives in a tail area the crate::buffer::BufferBuilder appends after the root record.

Structs

FieldOffset

One field’s slot inside a record.

OffsetTable

Computed offset table for a schema’s flat record area.

SchemaLayout

Schema-level layout entry point. Computes the offset table for the flat record area; tail-area layout (for String / List in Phase 2.b) will be returned through a sibling helper once those types land.

Enums

FieldKind

How a field is stored relative to the buffer record.

LayoutError

Reasons offset computation can fail.

ListElementKind

Phase 10-c: per-element layout descriptor for a List<T> field.