testing/cross_backend/rust_spine_stub_backend_config.ts

Cross-process BackendConfig preset for the non-domain spine consumer, testing_spine_stub — a Rust binary that mounts only the spine surface (auth / account / admin / audit / role-grant offers) with no domain layer. fuz_app drives it from src/test/cross_backend/*.cross.test.ts to verify its TS spec against the Rust spine end-to-end with no domain implementation in the loop — drift becomes a fuz_app failure rather than a downstream consumer's failure with mixed signals.

Binary discovery — env-supplied, never hardcoded. The binary lives in a sibling Rust workspace, not in fuz_app, so the preset never bakes a path in. FUZ_TESTING_RUST_SPINE_STUB_BIN (or the binary_path option) must point at a prebuilt binary; the preset throws a clear error when neither is set rather than guessing. Build once with cargo build -p testing_spine_stub --release and point the env var at the resulting target/release/testing_spine_stub; operators / CI cache the binary across runs for fast spawns.

Operator setup — the target Postgres database must exist before the harness runs (the harness never issues CREATE DATABASE, to avoid forcing a CREATEDB grant on the test role):

The binary self-wipes the auth-namespace schema on every boot (FUZ_TESTING_RESET_DB_ON_STARTUP=true, set by the Rust-family builder), so no manual DROP TABLE between sessions is needed; per-test reset is the orthogonal _testing_reset RPC action default_cross_process_setup fires.