# AGENTS.md

This workspace builds `landlock-run`, a Landlock self-restrict-then-exec launcher: a small, auditable confinement binary distributed as prebuilt per-platform npm packages, plus the thin JS entry package that resolves it and speaks its CLI contract. The source of record is the `deepseek-harness` repository's `native/landlock-run/`; the `node-addon-landlock-run` repository is the release mirror this tree is exported to for packing and publishing (procedure: `native/README.md` in the harness repo). Make changes in the source of record, never only in the mirror.

## Pre-release stance

The project is pre-1.0. Prefer the correct public shape over compatibility shims: if a package name, exported field, layout, or contract detail is wrong, rename it and update all references in the same change. Do not add deprecated aliases unless a stable release already needs them.

## Runtime safety rules

- Every tool must fail closed. If a ruleset cannot be created or the kernel does not enforce it, exit non-zero WITHOUT exec'ing the wrapped command. Never run unconfined as a fallback.
- Runtime binaries and the entry packages take NO environment-variable overrides: which binary confines a process must never be decidable by the ambient environment. Test injection is by function parameter; the `NALR_*` prefix is for build/test orchestration only.
- Kernel UAPI is self-defined in the C source (verbatim from the kernel headers), keeping builds independent of toolchain header vintage and making the definitions part of the audit record.
- No libraries beyond libc, linked statically against musl. The audit surface of a tool is its C source plus the kernel's stable syscall contract.
- The CLI contract of each tool ([docs/cli-contract.md](docs/cli-contract.md)) is the cross-repo compatibility surface: argv grammar, exit codes, and report lines change only with a version bump and a changelog entry, and consumers parse them only through the entry package.
- There is deliberately NO install-time build fallback: a host without a matching platform package gets a nonexistent launcher path, the consumer's probe fails, and the consumer falls closed — that degradation is part of the design, not a gap to fill with node-gyp.

## Repository layout

```text
packages/entry/     Published entry package: JS seam (resolve/probe/grants) + the C source.
packages/linux-*/   Published per-platform packages: one prebuilt static binary, no JavaScript.
scripts/            Build, matrix derivation, prepack gates, and release orchestration.
test/               Plain-node behavioral tests (entry seam + real-kernel launcher proofs).
docs/               Architecture, packaging, CLI contract, release, support matrix, naming.
```

## Commands

```sh
pnpm install
pnpm build:ts        # entry packages → lib/
pnpm build:native    # this Linux architecture's binaries (needs musl-tools); fails fast elsewhere
pnpm typecheck
pnpm test            # entry tests everywhere; launcher tests need linux + built binary
```

## Packaging invariants

- The package matrix is explicit, checked-in metadata: `packages/<name>/package.json` (`os`, `cpu`), `packages/<name>/prebuilds.json` (the binaries that may exist there), and [docs/support-matrix.md](docs/support-matrix.md) stay synchronized when the matrix changes. `scripts/github-matrix.mjs` derives CI and release matrices from it; nothing else enumerates platforms.
- Platform package names contain platform only (`-linux-x64`), never tool variants — those stay inside `prebuilds.json`. Static musl linking is why there is no libc suffix: one binary serves glibc and musl distros.
- Platform packages ship no JavaScript; the entry package resolves them to file paths. Backends prove themselves at runtime through the functional probe, never through metadata trust.
- Builds are native-only: each architecture compiles its own binary on its own runner (CI is the builder of record); no cross toolchain enters the repo.
- Every tarball is gated at pack time: platform packages refuse to pack without their declared binaries present, executable, and in the right ELF architecture (`verify-launcher-binary.mjs`), entry packages without built `lib/` (`verify-entry-lib.mjs`), and the release pipeline byte-pins installed binaries against the workspace builds (`verify-packed-install.mjs`).
- Platform tarballs are packed with `npm pack`, never `pnpm pack`: pnpm's pack path strips the executable bit (observed on 11.7.0), shipping a launcher no consumer can spawn. `pack-release.mjs` encodes the split; the rehearsal asserts executability of the installed copy so a regression fails loudly instead of masquerading as a non-enforcing kernel.
- Generated artifacts stay out of git: `packages/*/bin/`, `packages/*/lib/`, `dist/`, `.release/`, `*.tsbuildinfo`. Ignore rules live in the ROOT `.gitignore` only — a package-nested ignore file can silently drop payload from tarballs.

## Documentation

User-facing docs are English. Keep the README focused on install, usage, and support status; durable design decisions belong in docs/ alongside the code, and the current implemented shape belongs in [docs/architecture.md](docs/architecture.md).
