Current limitations

Generic language authoring is low-level

Implemented: typed package/contribution planning, artifact routing, runtime assembly, policy and lifecycle.

Not implemented as a high-level authoring product:

• grammar or parser generation;
• binder/type-system DSL;
• automatic derivation of verifier and backend contracts from operations;
• IDE/editor workbench;
• incremental parsing protocols;
• stable 1.0 compatibility.

The current SDK helps compose implementations; it does not generate a language implementation.

Backend-neutral runtime status

Backend-neutral artifact/session contracts and generic typed route execution are implemented. The remaining limitations are different:

• Wist shipped presets use the canonical typed package/runtime path, but the generic SDK still exposes planning-only untyped artifact contracts that cannot participate in executable routes;
• the generic API is alpha and may evolve;
• a third independent production-scale backend has not yet validated every abstraction boundary;
• high-level backend authoring ergonomics remain sparse.

Do not describe backend-neutral artifacts as future-only work.

Wist-specific boundaries

• Wist remains the most mature language path;
• Wist compiler module authoring still contains hidden token, parser-priority, visitor and Bytecode-tag contracts;
• Bytecode tag taxonomy and verification are incomplete;
• the callable-first SSA route supports a bounded subset and may round-trip opaque managed calls without optimizing them;
• Prefer falls back only for known unsupported-route diagnostics.

Security

Restricted dialects and runtime policies constrain selected components. They are not hardened sandboxing. Hostile input or hostile extension packages require external process/environment isolation, resource controls and a trust model.

Performance

Only tied, reproducible benchmark scenarios support performance claims. Compilation, Evaluate, interpreter execution and prepared typed-delegate invocation are separate workloads.

Documentation and ecosystem

• external package authoring is new and has limited third-party use;
• generic API reference is not yet generated from a stable public API baseline;
• version negotiation and migration tooling are early;
• documentation snippets are protected by repository checks but do not replace consumer-level compatibility tests.