No barrel imports

Terreno avoids barrel imports — imports that resolve through an index.ts / index.tsx file that only re-exports other modules.

Why

• Clearer dependencies: each import names the file that defines the symbol.
• Faster tooling: bundlers and TypeScript do less re-export chasing.
• Fewer cycles: internal barrels (especially package index files) are a common source of circular dependencies.

Allowed

• Published package APIs — cross-package imports like @terreno/api, @terreno/ui, and @terreno/rtk use each package's public src/index entry. That is intentional.
• Package public entry files — api/src/index.ts, ui/src/index.tsx, etc. may re-export for npm consumers. Do not import those barrels from inside the same package.
• Expo Router routes — app/**/index.tsx files are route entries, not barrels.

Not allowed

Internal barrel index files do not exist in this repo — the Biome noBarrelFile override bans creating them, so a directory import like ../models has nothing to resolve to and fails to compile.

Importing a directory that resolves to a re-exporting index file:

// Bad — resolves to models/index.ts
import {User} from "../models";

// Good — imports the defining module
import {User} from "../models/user";

// Bad — store/index.ts was a barrel of sdk/appState/utils
import {useGetMeQuery} from "@/store";

// Good
import {useGetMeQuery} from "@/store/sdk";
import store, {useAppDispatch} from "@/store/index";

Enforcement

No generation step is required — internal barrel index files are banned outright, so there is never a list of barrels to keep in sync.

• Biome noBarrelFile override (root biome.jsonc): bans internal barrel index.ts / index.tsx files during lint. Package public entries (src/index.ts[x]) and Expo Router routes (app/**) are exempt.
• Biome plugin: biome/plugins/no-barrel-imports.grit — a small static GritQL plugin that flags path-alias directory imports (@/store, @components, …) in the packages that define those aliases (example-frontend, admin-spa, demo).
• CI: bun run check:no-barrel-imports — resolution-based safety net that fails if any internal barrel index file exists or any import resolves through one (see root package.json → terreno.policies.noBarrelImports).
• AI rules: .rulesync/rules/00-root.md and package .ai/guidelines/core.md files

When scaffolding new code (MCP bootstrap, examples), always generate direct module paths — never models/index, @/store, or @components without a concrete file.