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Fence

What it does

The fence³⁹ is the compiler checks, lint rules, and hooks that reject prohibited code and shortcuts. The fence³⁹ explains the idea. Effect describes work with typed failures³⁶ and required services. A service is a named interface for one job.¶

XState defines state machines: named states and the events that permit movement between them. These checks enforce it today:¶

• Type-aware Oxlint runs Ultracite’s core rules and the repo’s plugins in scripts/oxlint-plugin-*.ts. The plugins cover boundaries, patterns, no comments⁷, Effect tests, and XState with Effect. Vendored anti-slop rules also run. All use error severity in oxlint.config.ts.¶
• rat-stack-boundaries/no-core-adapters keeps provider adapters out of core. An adapter implements an application-owned interface for a specific provider.¶
• Ports, interfaces named for application jobs, stay in core. Fixture tests prove the import boundary.¶
• Effect language-service diagnostics, compiler messages about Effect code, are set to error in tsconfig.base.json. effect-tsgo patch runs in prepare, so both tsc and the editor report failures.¶
• Lefthook runs pnpm check and pnpm test before every commit.¶
• scripts/vcs-command-policy.js blocks git … --no-verify. The Pi extension, the Claude Code hook, and the Cursor hook all call that one file.¶
• Continuous integration (CI) runs pnpm turbo run check test build after a fresh dependency install.¶
• The install uses the exact versions in the lockfile; it cannot update that file.¶

The standard

• A commit runs check and test, and a failure stops it.¶
• No agent harness configured in the repo can bypass the hooks with --no-verify.¶
• Effect diagnostics fail the typecheck.¶
• Code carries no prose comments. Tool directives need a reason after --; type assertions need a one-line SAFETY: statement of the condition that makes the assertion safe. Plain JS may keep type-only JSDoc. No comments⁷ and repo law give the full exception policy.¶
• Every lint or diagnostic override names its rule and gives a reason.¶
• The number of overrides only shrinks. The debt ledger, a report counting lint and diagnostic exceptions, publishes the count by kind.¶
• A new lint rule ships with a test that runs real Oxlint against fixtures.¶
• Loosening any of this needs the owner’s sign-off.¶

How to check

• pnpm turbo run check test build runs everything CI runs.¶
• echo '{"tool_name":"Bash","tool_input":{"command":"git commit --no-verify"}}' | node scripts/hooks/block-git-no-verify.mjs prints a deny decision with the reason.¶
• pnpm --filter @rat-stack/core test runs the fixture tests for the boundary, pattern, no-comment, and unknown-parameter rules, and the command policy test.¶
• The boundary fixtures in packages/core/test/boundaries-rule.test.ts reject adapter imports from core and accept composition outside it.¶
• curl -sS https://ratstack.sh/debt.md shows the current override count.¶

Last changed 2026-10-07 in f77853d. Source on GitHub. Change log.