[Gudge (MGudgin)]

This PR deletes sdk/node/src/helper.ts, the subprocess launch path behind the retired spawnSandboxFromConfig family. #1385 replaced that path with the in-process v1 APIs and #1479 removed its last importer. Since then nothing in the package has imported it, and the package exports map (., ./v1, ./package.json) never exposed it, so only its own unit tests still exercised it. Docs that still described spawnSandboxFromConfig or an SDK-level experimental option now describe the v1 behaviour.

Details

• Delete helper.ts, the FileLogger it alone used, and internal-only v1 leftovers (ContainmentTypes, LegacyContainmentAliases, ExperimentalBackends, legacyConfigAliasUnsupportedReason, findSeatbeltExecutable). None is exported from @microsoft/mxc-sdk/v1.
• Remove the resolveExecutableAndArgs and FileLogger unit tests and drop logger.test.js from test:unit.
• Document that the published v1 SDKs never authorize experimental backends. Node v1 passes experimental = false to the native entry points, the .NET switch is private, and Node v1 rejects microvm. So MicroVM and other experimental features run through wxc-exec --experimental (versioning.md, nanvix.md, the authoring guide, container-lifecycle.md §7.2).
• Point the IsolationSession one-shot note at the Node v1 create-and-run operations and drop removed APIs from a Rust comment.

References

• Align Rust, .NET, and Node SDKs around versioned container APIs #1385 (in-process v1 APIs), Align Node v1 conformance with the published 1.0 contract #1479 (removed the last helper.ts importer)
• Remove the Electron Playground #1546 removes the Electron Playground, the remaining caller of spawnSandboxFromConfig

Tests

• npx --no-install tsc -p . in sdk/node: passed.
• npx --no-install tsc in sdk/node/tests/unit: passed.
• node --test --test-reporter=tap <the test:unit file list> in sdk/node: 438 tests, 420 passed, 18 skipped, 0 failed.
• cargo fmt --all -- --check in src: passed.
• git diff --check: passed.

Microsoft Reviewers: Open in CodeFlow

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[Copilot]

🟢 Approval recommended

The removed implementation has no active consumers or supported exports, and the deleted tests cover only retired functionality.

No open issues 🎉

What changed in this PR

Removes the unused Node subprocess launch implementation left behind by the migration to in-process v1 APIs, without changing supported exports.

Changes:

• Deletes retired launch helpers, logging code, and their tests.
• Removes unused internal types and executable discovery helpers.
• Updates documentation to describe v1 operations and experimental-backend restrictions.

File	Description
src/​mxc-sdk/​src/​backends/​isolation_session/​common/​one_shot.rs	Removes retired API names from a comment.
sdk/​node/​tests/​unit/​sandbox.test.ts	Removes retired helper tests.
sdk/​node/​tests/​unit/​logger.test.ts	Deletes logger tests.
sdk/​node/​src/​v1/​types.ts	Removes unused internal constants and alias validation.
sdk/​node/​src/​v1/​platform.ts	Removes unused macOS executable discovery.
sdk/​node/​src/​logger.ts	Deletes the unused file logger.
sdk/​node/​src/​helper.ts	Deletes subprocess launch helpers.
sdk/​node/​package.json	Removes the deleted logger test from the unit command.
docs/​development/​guides/​authoring-a-new-feature.md	Replaces obsolete SDK experimental-option guidance.
docs/​development/​architecture/​versioning.md	Documents v1 experimental-backend restrictions.
docs/​development/​architecture/​container-lifecycle.md	Clarifies experimental authorization.
docs/​development/​architecture/​backends/​isolation-session/​oneshot.md	References Node v1 create-and-run operations.
docs/​backends/​nanvix/​nanvix.md	Directs experimental MicroVM usage to the CLI.

_{Review effort: Balanced}

[Copilot]

🟡 Changes recommended

The versioning guide documents a native error code where Node v1 instead rejects experimental containment values during request validation.

1 open issue

• Distinguish SDK validation from native containment authorization errors · New

_{Review effort: Balanced}