Gold groundwork: code review, security-review procedure, REUSE compliance

.github/workflows/ci.yml

@@ -3,8 +3,8 @@
 #
 # The same three OTP/Elixir pairs as beam_mcp (floor, pinned, head): format, compile with
 # warnings as errors, Credo --strict (.credo.exs), the Hex audit (retired packages and OSV
-# advisories against mix.lock), the suite; and the DCO sign-off on every commit, as beam_mcp's
-# gate workflow checks it. Actions pinned by commit SHA with the version beside it.
+# advisories against mix.lock), the suite; the REUSE lint over the tree; and the DCO sign-off
+# on every commit, as beam_mcp's gate workflow checks it. Actions pinned by commit SHA with the version beside it.
 name: ci
 
 on:
@@ -42,6 +42,16 @@ jobs:
       - run: mix hex.audit
       - run: mix test
 
+
+  reuse:
+    name: REUSE lint
+    runs-on: ubuntu-24.04
+    timeout-minutes: 5
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      - name: every file carries copyright and licence information (the version beam_mcp pins)
+        run: pipx run reuse==6.2.0 lint
+
   dco:
     name: DCO sign-off
     runs-on: ubuntu-24.04

.gitignore

@@ -1,3 +1,6 @@
+# SPDX-FileCopyrightText: 2026 Sudo Apt Holdings LLC
+# SPDX-License-Identifier: Apache-2.0
+
 /_build/
 /cover/
 /deps/

.tool-versions.license

@@ -0,0 +1,2 @@
+SPDX-FileCopyrightText: 2026 Sudo Apt Holdings LLC
+SPDX-License-Identifier: Apache-2.0

CHANGELOG.md

@@ -7,6 +7,13 @@ SPDX-License-Identifier: Apache-2.0
 
 ## [Unreleased]
 
+### Added: gold groundwork (no code change)
+
+- `docs/security-review.md`: how a security review of this package is done, a checklist centred
+  on the key, and its record, empty until the first review. `CONTRIBUTING.md`: a code-review
+  section. REUSE compliance: `.gitignore` headed, `.tool-versions`, `mix.lock` and `NOTICE`
+  with `.license` sidecars, `LICENSES/Apache-2.0.txt`, and `reuse lint` in CI.
+
 ### Changed: governance (no code change)
 
 - `GOVERNANCE.md` names two continuity holders, as on `beam_mcp`: `znmead` (the Maintain role

CONTRIBUTING.md

@@ -39,6 +39,28 @@ Erlang/OTP 27 or newer and Elixir 1.17 or newer, the same floor as `beam_mcp`. C
    (`test/beam_mcp/signer/no_key_source_test.exs`) red when the rule is broken: plant the
    break, show it red, restore it.
 
+## Code review
+
+**How it is done.** Every change reaches `main` through a pull request, the maintainer's
+included, rebased after CI is green on all three OTP/Elixir pairs. The reviewer reads the diff,
+the commit messages and the CI results, and runs the suite locally for any change under `lib/`.
+
+**What must be checked.**
+- The change does what its message says, and nothing else.
+- New or changed behaviour has tests; a fix has a test that was seen failing first.
+- **The key:** it is read from `opts[:private_key]` and nowhere else; no result, error term or
+  raise carries it; nothing is kept after the call. The key-source census
+  (`test/beam_mcp/signer/no_key_source_test.exs`) still passes for the right reason, and a
+  change to how the key is handled is shown red against a planted break.
+- `SECURITY.md`, `docs/assurance-case.md` and the README change with the behaviour they describe.
+- Sign-off on every commit, no attribution trailers, no key or secret in the diff.
+
+**What is acceptable.** All of the above hold, CI is green, and the reviewer can say why the
+change is correct; otherwise it is sent back with the reason. **Who reviews:** the maintainer
+reviews every pull request; the continuity holders in `GOVERNANCE.md` may review as well. A
+review by a person other than the author on at least half of all changes is the project's aim;
+the pull requests show who reviewed each one.
+
 ## Coding style
 
 The Elixir community's: the output of `mix format` (this repository's `.formatter.exs`) and

LICENSES/Apache-2.0.txt

@@ -0,0 +1,201 @@
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NOTICE.license

@@ -0,0 +1,2 @@
+SPDX-FileCopyrightText: 2026 Sudo Apt Holdings LLC
+SPDX-License-Identifier: Apache-2.0

docs/security-review.md

@@ -0,0 +1,53 @@
+<!--
+SPDX-FileCopyrightText: 2026 Sudo Apt Holdings LLC
+SPDX-License-Identifier: Apache-2.0
+-->
+
+# Security review
+
+How a security review of this package is done, and the record of each one. A review is a
+person reading the code against the package's security claims; the tests, the census and Credo
+support it and do not replace it. One is done at least every five years, and before `1.0.0`.
+`beam_mcp`'s own procedure
+([docs/security-review.md](https://github.com/ScriptKittyOS/beam_mcp/blob/main/docs/security-review.md))
+covers the bytes this package signs.
+
+## What it is measured against
+
+`SECURITY.md` ("What you can expect from this package") and the claim, threat model and trust
+boundaries in `docs/assurance-case.md`.
+
+## The checklist
+
+Each item is answered with what was read, what was tried, and what was found.
+
+1. **One source for the key.** Read `lib/beam_mcp/signer/ed25519.ex` in full. Is the key read
+   from `opts[:private_key]` only? Does the census's regex and call list still describe the
+   compiled module (`test/beam_mcp/signer/no_key_source_test.exs`)?
+2. **Nothing kept.** No process state, table, persistent term, application environment or
+   file after a call; a reference (`fn -> key end`) called once and dropped.
+3. **Nothing printed.** Every result is a signature or a fixed error term; no clause can raise
+   on its arguments. Try a map for the options, a non-binary for the bytes, a wrong-length key
+   and a reference returning the wrong thing, and read what comes back and what a log would show.
+4. **The signature.** Ed25519 over exactly the bytes given, verified independently with
+   `:crypto.verify/5` and through `beam_mcp`'s canonical bytes; no prehash, no other algorithm.
+5. **Randomness.** None is used; confirm that no key or nonce is generated in `lib/`.
+6. **Supply chain and release.** `mix.lock` against `mix hex.audit`; the `beam_mcp` requirement;
+   workflow permissions and pinned actions; a release tarball rebuilt with
+   `tools/release_tarball.sh` and compared with hex.pm's checksum; the tag's signature
+   (`docs/verifying-releases.md`).
+7. **The pages.** Does the assurance case, `SECURITY.md` and the README still describe the code?
+
+## After a review
+
+Findings go through `SECURITY.md` (a private advisory where warranted), each with an issue or a
+pull request. The review is recorded below in the pull request that adds the row.
+
+## Record
+
+| date | reviewer | commit | scope | findings |
+|---|---|---|---|---|
+
+No review has been recorded yet. The audit that found and closed the key-in-exception defect
+(`docs/assurance-case.md`, "Closed") was automated-assisted groundwork for the first review, not
+a review under this page's definition.

mix.exs

@@ -33,7 +33,8 @@ defmodule BeamMCP.Signer.Ed25519.MixProject do
           "docs/architecture.md",
           "docs/assurance-case.md",
           "docs/roadmap.md",
-          "docs/verifying-releases.md"
+          "docs/verifying-releases.md",
+          "docs/security-review.md"
         ]
       ],
       aliases: [check_otp: &check_otp!/1]

mix.lock.license

@@ -0,0 +1,2 @@
+SPDX-FileCopyrightText: 2026 Sudo Apt Holdings LLC
+SPDX-License-Identifier: Apache-2.0