Stock JS capsules uninstallable on kernels ≥ 0.9.1 — astrid:process/host@1.0.0 missing from the lifecycle linker

[eren-karakus0]

Summary

Installing any component built with the published JS packages fails on astrid 0.9.1 and 0.9.4 with:

lifecycle dispatch failed: Unsupported entry point: Failed to instantiate WASM
component for lifecycle: component imports instance `astrid:process/host@1.0.0`,
but a matching implementation was not found in the linker

@unicity-astrid/build 0.1.0 synthesizes a world that imports astrid:process/host@1.0.0, and the SDK bridge imports the specifier unconditionally (esbuild keeps it — every JS capsule links every SDK module whether used or not). Kernels ≥ 0.9.1 register process@1.1.0 but no longer register a 1.0.0 implementation in the lifecycle linker, so every stock JS capsule is uninstallable on current kernels.

The astrid:process/host@1.0.0 string is still present in the binary, which suggests an unintended registration gap rather than a deliberate removal.

Reproduction

1. npm i @unicity-astrid/sdk@0.1.0 @unicity-astrid/build@0.1.0
2. Build any capsule (even a no-op @install that just logs).
3. astrid capsule install . → the error above.

Impact

The published JS SDK/build toolchain produces no installable artifact on released kernels; JS capsule authors are blocked at step one.

Workaround we used

Drop the import on both sides — stub spawn / spawnBackground in sdk/dist/process.js, and remove import astrid:process/host@1.0.0; from the world template in build/src/index.mjs. Our capsule never spawns processes (the SDK documents astrid:process as optional per target). The component shrank 13.10 MB / 170 host imports → 12.30 MB / 142 and then installed and ran verified sessions on 0.9.4.

Suggested fix (any one)

• Re-register the 1.0.0 shim in the lifecycle linker, or
• Publish SDK/build packages targeting the current WITs, or
• Make the build tree-shake host domains the capsule does not use.

Environment

• @unicity-astrid/sdk 0.1.0, @unicity-astrid/build 0.1.0 (npm)
• astrid 0.9.1 and 0.9.4 release binaries, x86_64-unknown-linux-gnu
• Ubuntu 24.04 (WSL2), Node 22
• Capsule: TypeScript, standard TC39 decorators (experimentalDecorators: false, ES2022) → astrid-js-build → ComponentizeJS → wasm32-wasip2

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Part of a small batch of findings from building a non-trivial JS capsule. Related: #20 (decorator registry read before construction). A minimal reproducing repo and the exact patch set are available on request.