platform_capability_matrix.md

Platform Capability Matrix

This document is the human-readable companion to artifacts/platform_capability_matrix_v1.json for asupersync-idea-wizard-fifth-wave-3gaiun.12.

The matrix records the coarse support policy for four host roles:

platform id	host role	scope
linux	native	Linux runtime with epoll, optional io_uring, filesystem, process, signal, and feature-gated TLS lanes.
macos_bsd	native	BSD-family runtime with kqueue and Unix filesystem, process, and signal semantics.
windows	native	Windows runtime with IOCP and narrower process/signal semantics.
browser	wasm host	Browser package and host APIs. This is not native OS parity.

The checked artifact is intentionally conservative. It is a routing and claim-boundary map, not a live platform probe.

Status Policy

status	counts as supported	pass verdict allowed	meaning
supported	yes	yes	The capability is admitted for the platform when its cited proof lane is fresh.
feature_gated	no	no	A feature, package, target, or host lane must be selected and proven separately.
partial	no	no	The platform has a narrower subset; the row must render as skip or fail until a narrower claim is made.
unsupported	no	no	The host does not provide the capability.
not_applicable	no	no	The capability belongs to another host role.

Only supported rows may include pass in runtime_verdicts. feature_gated, partial, unsupported, and not_applicable rows are kept so operators can see why a feature is unavailable, but they never count as green support evidence.

Capability Families

family	examples
reactor	epoll, kqueue, IOCP, browser reactor, io_uring feature lane
filesystem	native file operations, sparse files, symlinks, atomic rename, browser storage exclusion
process	child process management, wait, pipe, and cancellation cleanup
signal	Unix signal streams, Windows subset, Ctrl+C, graceful shutdown
tls	rustls feature lane and root-store policy
browser	fetch, WebSocket, storage, entropy, time, and host API capabilities
toolchain	Rust 2024 nightly, native targets, and wasm package constraints

The contract test at tests/platform_capability_matrix_contract.rs verifies that each required capability covers every required platform, cites live source or docs paths, and carries a nonempty no-claim boundary.

Validation

Use the remote-only proof lane declared in the artifact:

RCH_REQUIRE_REMOTE=1 rch exec -- env CARGO_TARGET_DIR="${TMPDIR:-/tmp}/rch_target_platform_capability_matrix" CARGO_INCREMENTAL=0 CARGO_PROFILE_TEST_DEBUG=0 RUSTFLAGS='-D warnings -C debuginfo=0' cargo test -p asupersync --test platform_capability_matrix_contract --no-default-features -- --nocapture

Local Cargo fallback is not evidence for this contract.

No-Claim Boundaries

This matrix does not prove broad workspace health, release readiness, live RCH fleet availability, performance, runtime correctness, or cross-platform e2e success. It also does not replace ATP host probes, browser package fixture evidence, or feature-specific proof lanes such as io-uring, tls, and wasm/browser support.

Skipped, partial, feature-gated, unsupported, and not-applicable rows are negative or deferred evidence. They are never support evidence.