Migrated from a local Wesley Method backlog card after adopting METHOD v2.1.0 tracker doctrine.

• Source path: docs/method/backlog/up-next/RUNTIME_wasm-capability-versioning-and-state.md
• Original filesystem lane: up-next
• Canonical Method lane label: lane:asap
• Legend: RUNTIME
• Migration issue: Migrate Wesley Method backlog to GitHub Issues #548
• Migrated on: 2026-06-04

Original Local Backlog Card

WASM capability versioning and state

• Lane: up-next
• Legend: RUNTIME

Why now

The capability ABI needs compatibility and state semantics before it becomes a
real plugin boundary. Hosts must know whether a kernel can run a capability, and
capabilities must not hide mutable state behind portable compiler truth.

Hill

The first WASM capability ABI defines semver compatibility, rejection
diagnostics, and a stateless default model with explicit future resource
handles.

Done looks like

• kernel semver and capability ABI semver are documented separately
• capabilities declare ABI version range and optional minimum kernel feature
  set
• hosts reject unsupported combinations with typed diagnostics before execution
• the first portable ABI profile is stateless
• any future state enters through explicit resources such as registry snapshots,
  cache handles, or session handles
• fixture proves hidden state cannot alter pure capability output

Repo Evidence

• docs/design/0009-rust-core-and-wasm-capability-abi/rust-core-and-wasm-capability-abi.md
• crates/wesley-core/src/domain/capability.rs
• crates/wesley-core/tests/module_capability_registry.rs
• docs/method/backlog/up-next/RUNTIME_wasm-host-function-governance.md
• docs/method/backlog/bad-code/EVIDENCE_module-load-report-release-artifact.md

Current Slice Status

Rust-native metadata, registry fixtures, ABI version range diagnostics,
stateless resource-handle rejection, and hermetic cross-host fixture checks now
exist. Remaining work is the full runtime ABI: actual WASM execution,
resource-handle implementation, kernel feature negotiation, and release
artifact reporting.