ADR 14: Records require explicit bridge definitions

Date: 2026-06-16

Context

Accepting or returning a record across the boundary needs a known memory layout.

Decision

Clojure records participate through defrecordz, not automatic conversion of arbitrary records.

Consequences

A bridged record gives Zig a known field order, field types, alignment, layout, and ownership rules; an arbitrary Clojure record carries none of these.

Alternatives

Automatic record-to-struct conversion was considered; without a declared layout it cannot produce a sound Zig struct.

Amendment (2026-06-27)

The record bridge now carries buffer and :string fields in addition to scalars and enums. A field may be [:bytes [:slice :u8]] (to a byte[]), [:owned [:slice T]] or [:slice T] (to a vector), or :string (an owned UTF-8 buffer marshalled to a String). Each buffer field lowers to a usize pointer and a usize length in the wire extern struct, since a Zig slice is not a C type, so a record can model a multi-value result. The ownership and free protocol for those fields is ADR 21; the bridge itself stays explicit through defrecordz and deftypez.