Spin adapter cannot serve: spin-sdk 6 imports wasi:http@0.3.0-rc, unsupported by released Spin runtimes

[aram356]

Summary

The Spin adapter compiles to a wasm32-wasip2 component and passes its router-level contract tests under wasmtime, but it cannot actually serve: spin up fails to link on every released Spin runtime.

Reproduction

edgezero-cli serve --adapter spin
# or directly:
spin up --from crates/mocktioneer-adapter-spin/spin.toml \
        --runtime-config-file crates/mocktioneer-adapter-spin/runtime-config.toml

Fails with (Spin 3.6.3):

Error: component imports instance wasi:http/types@0.3.0-rc-2026-03-15,
but a matching implementation was not found in the linker

Root cause

cargo tree shows the chain:

mocktioneer-adapter-spin → edgezero-adapter-spin → spin-sdk v6.0.0
  → wasip3 v0.6.0+wasi-0.3.0-rc-2026-03-15

spin-sdk 6.0.0 imports wasi:http@0.3.0-rc, which no released Spin runtime provides (they expose wasi:http@0.2). This is an SDK/runtime ABI mismatch.

Why this can't be fixed in mocktioneer

edgezero-adapter-spin pins spin-sdk 6 as a workspace dependency with no feature lever to select the wasi:http@0.2 ABI, so mocktioneer cannot downgrade or opt out. The fix belongs upstream in EdgeZero's spin-sdk pin (align the SDK / generated component ABI / required Spin CLI runtime version).

Impact

• spin up / spin deploy are unusable → blocks As developer I want to deploy moctkioneer to Fermyon cloud #84 (deploy to Fermyon Cloud).
• CI cannot add a spin up smoke test; only the wasmtime router contract test runs.
• No auction-through-adapter coverage for Spin (Fastly and Cloudflare have it as of PR Adapt Mocktioneer to edgezero v0.0.4 (extensible CLI, typed config, introspection routes) #110).
• Fastly, Cloudflare and Axum are unaffected.

Current state

Documented as a known limitation in docs/guide/configuration.md and CLAUDE.md (PR #110) rather than shipping a knowingly-red CI gate.

Done when

• EdgeZero aligns the spin-sdk pin / component ABI with a released Spin runtime.
• spin up serves mocktioneer locally.
• CI gains a spin up smoke test that curls /.
• Spin gains a config-seeded auction contract test (parity with Fastly/Cloudflare).
• The limitation notes in docs/guide/configuration.md + CLAUDE.md are removed.