chore(pnpm): add security settings for supply chain attack prevention

[ryoppippi]

Summary

• Add pnpm security settings to protect against supply chain attacks
• Document the security settings in .claude/rules/pnpm-usage.md
• Add missing symlink for nix-workflow.md to .cursor/rules

Security Settings Added

Setting	Purpose
strictDepBuilds: true	Blocks lifecycle scripts (postinstall, etc.) by default. Only packages in onlyBuiltDependencies can run build scripts.
blockExoticSubdeps: true	Blocks dependencies from non-registry sources (Git repos, tarball URLs).
trustPolicy: no-downgrade	Prevents trust level downgrades between versions (e.g., from GitHub OIDC to basic auth).

Reference

• https://pnpm.io/settings
• StackOneHQ/disco#463

Test plan

• pnpm install completes successfully with new settings (tested after removing node_modules)

---

Summary by cubic

Adds pnpm security settings to block risky install scripts and non-registry dependencies, and documents how to use them. Also adds a symlink for the Nix workflow rules.

• Dependencies

  • strictDepBuilds: blocks lifecycle scripts by default; whitelist via onlyBuiltDependencies.
  • blockExoticSubdeps: blocks Git/tarball subdependencies.
  • trustPolicy: no-downgrade, now documented.

• Migration

  • No action needed; pnpm install works as usual.
  • If a dependency needs build scripts, add it to onlyBuiltDependencies.

^{Written for commit 465095f. Summary will update on new commits.}

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/StackOneHQ/stackone-ai-node/@stackone/ai@307

commit: 465095f

[Copilot]

Pull request overview

Adds pnpm workspace-level security hardening to reduce supply-chain risk, and documents the configuration for contributors and editor tooling.

Changes:

• Enable pnpm security settings (strictDepBuilds, blockExoticSubdeps, trustPolicy) in pnpm-workspace.yaml
• Document the new pnpm security posture and maintenance guidance in .claude/rules/pnpm-usage.md
• Add a .cursor/rules entry for the Nix workflow rule via link/symlink

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
pnpm-workspace.yaml	Introduces pnpm security settings aimed at preventing risky installs/build scripts and trust downgrades.
.cursor/rules/nix-workflow.mdc	Adds the missing Cursor rule entry pointing at the shared Nix workflow documentation.
.claude/rules/pnpm-usage.md	Documents the pnpm security settings and how to handle build-script exceptions.

---

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[Copilot]

The comment "Prevents Shai-Hulud-style worm attacks" is an informal / unclear reference and also overstates what strictDepBuilds guarantees. Consider replacing it with a neutral description (e.g., "mitigates supply-chain risk from dependency lifecycle scripts") and/or link to a concrete advisory if you want to reference a specific incident.

Suggested change

	# Prevents Shai-Hulud-style worm attacks that exploit automatic script execution
	# Mitigates supply-chain risk from dependency lifecycle scripts that run automatically

[Copilot]

Similar to above: the "Prevents PhantomRaven-style attacks" comment is hard to validate and may not be meaningful to future maintainers. Recommend rewording to a concise, incident-agnostic explanation of what blockExoticSubdeps enforces (and/or link to an external reference).

Suggested change

	# Prevents PhantomRaven-style attacks that bypass npm scanning
	# Reduces supply-chain risk from unvetted or externally sourced subdependencies

[cubic-dev-ai]

1 issue found across 3 files

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name=".claude/rules/pnpm-usage.md">

<violation number="1" location=".claude/rules/pnpm-usage.md:55">
P3: `blockExoticSubdeps` only blocks exotic sources for transitive dependencies, not for direct dependencies. Update the description to reflect its actual behavior.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P3: blockExoticSubdeps only blocks exotic sources for transitive dependencies, not for direct dependencies. Update the description to reflect its actual behavior.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At .claude/rules/pnpm-usage.md, line 55:

<comment>`blockExoticSubdeps` only blocks exotic sources for transitive dependencies, not for direct dependencies. Update the description to reflect its actual behavior.</comment>

<file context>
@@ -44,6 +44,21 @@ fish -c "<command>"
+| Setting | Purpose |
+|---------|---------|
+| `strictDepBuilds: true` | Blocks lifecycle scripts (postinstall, etc.) by default. Only packages in `onlyBuiltDependencies` can run build scripts. |
+| `blockExoticSubdeps: true` | Blocks dependencies from non-registry sources (Git repos, tarball URLs). |
+| `trustPolicy: no-downgrade` | Prevents trust level downgrades between versions (e.g., from GitHub OIDC to basic auth). |
+
</file context>

Suggested change

	| `blockExoticSubdeps: true` | Blocks dependencies from non-registry sources (Git repos, tarball URLs). |
	| `blockExoticSubdeps: true` | Blocks transitive dependencies from resolving non-registry sources (Git repos, tarball URLs); direct dependencies must still opt into those sources explicitly. |