The architecture documentation for ECHIDNA lives in
docs/ARCHITECTURE.md — the polyglot layout, the
dispatch path, the trust-hardening pipeline, and how the Rust core, Julia ML
sidecar, Idris2 ABI, Zig FFI and optional Chapel parallel layer fit together.
Related canonical documents:
docs/PROVER_COUNT.md— backend tier table and what each published count actually countsdocs/ROADMAP.md— stage map and current directiondocs/DEBT.md— known licence, documentation and code debt.machine_readable/descriptiles/META.a2ml— the machine-readable architecture record