Lispex chooses a closed, inspectable profile: fewer host-dependent choices, explicit exclusions, and one semantic authority for every backend.
Current guarantees
- Determinism is part of language identity, not merely a testing convenience.
- Unsupported behavior fails loudly instead of falling back to host globals or platform libraries.
- Evidence is scoped to named executions and provenance, never silently upgraded into a proof.
Boundaries
- Scope cuts are deliberate compatibility decisions, not promises to imitate every Scheme.
- Future backends must implement the profile; they do not redefine it.