Compile-time validation failure for a deployment prelude (Capability Prelude V1, plan §3 / §10).

Returned as {:error, %ValidationError{}} from PtcRunner.Lisp.Prelude.Compiler.compile/1 when the prelude SOURCE is malformed in a way that does not depend on a selected runtime (parse errors, reserved-namespace declarations, duplicate refs, bad visibility, invalid arity/signature metadata, and similar facts), and from PtcRunner.Lisp.Prelude.Attach.validate_requires/2 with the :prelude_attach_failed reason when a public export requires an upstream operation the selected runtime does not provide (plan §3 / §6A).

Fields

• reason — a stable, matchable atom. Compile-time reasons: :reserved_namespace, :reserved_name, :duplicate_ref, :invalid_visibility, :invalid_requires, :invalid_metadata, :qualified_self_reference, :missing_namespace, :invalid_namespace, :invalid_signature, :parse_error, :compile_error. Attach-time reason: :prelude_attach_failed.
• message — human-readable detail naming the offending namespace, symbol, or value. Must not contain secrets (plan §12).
• namespace — the declaring namespace when known, else nil.
• ref — the offending export ref when known, else nil.